Carolinas Roofing August 2011 – Let The Wind Blow

What a windy spring! As usual, the middle portion of our country has experienced tornado-strength winds, resulting in devastation and loss of lives. Additionally, a series of tornadoes in eastern North Carolina wreaked havoc. In late May, a deadly tornado also destroyed property in Massachusetts, a location that isn’t used to twisters.

Can we prepare a design for a roof system to withstand the forces of such an event? Although we cannot completely design for the magnitude of a tornado’s force or the swirling nature of a tornado’s wind, we can prepare a comprehensive design for normal wind conditions expected in the various regions of the country. Using this accepted design will allow a roof system to not only withstand wind pressures up to the established design wind loads, but also maximize the possibility of a roof to withstand a tornado event.

WIND DESIGN BACKGROUND

From the mid-1980s through the mid-’90s, research and testing was done to attempt to determine how physical conditions of a roof (slope, height, material, etc.) and demographic conditions of a roof’s location (expected maximum wind load, building occupancy, etc.) aff ected the actual wind pressures that could be expected. These studies culminated in an industry- and code-accepted standard that should be used to determine the expected maximum wind pressure for all roofs. That standard is published in the American Society of Civil Engineers Standard titled “Minimum Design Loads for Buildings and Other Structures.”

Chapter 6 of the standard, “Wind Loads,” is the basis for the International Building Code, which is the standard that most state building-code authorities follow. The 2009 North Carolina State Building Code states in section 1609.1.1, “Wind loads on every building or structure shall be determined in accordance with Chapter 6 of ASCE 7.”

ASCE 7 BASICS

It should be noted that in the development of the ASCE 7 standards, it was determined that a certain wind produces different wind pressures around a roof area. There are three distinct roof areas identified: Zone 1 is defined as the interior area of the roof that is not affected by forces associated with wind traveling vertically up the building’s walls; Zone 2 is identified by the perimeter of the roof that is affected by the wind coming vertically up the walls of the building and releasing at the roof level; Zone 3 is the zone commonly referred to as the corner zone where any Zones 2 intersect. The size of Zone 2, considered the edge, is determined within ASCE 7 based on the building parameters. Additionally, a Zone 2 will exist for ridges, hips and parapets under certain slopes.

Although there are many parameters associated with determining the actual design pressure for a roof, the most important ones are the following:

1. WIND SPEED: The wind speed can be determined for the Carolinas from Figure 6-1B of ASCE 7 (see page 45) or an equivalent wind-speed map located in a particular state’s building code.

2. ROOF SLOPE: The wind creates a more severe pressure for a low-slope roof than it does for a steep-slope roof.

3. BUILDING OCCUPANCY:
ASCE 7 uses a different Occupancy Category for buildings according to their intended use, which results in varying safety factors for the design wind loads to be used. Category I is predominantly for agricultural buildings. Category II is predominantly for buildings not in Categories I, III and IV. Category III is predominantly for schools and municipal buildings. Category IV is predominantly for hospitals and emergency related buildings. For example, a hospital roof requires a higher design pressure than an offi ce building with all other conditions constant.

4. TOPOGRAPHY: ASCE 7 defi nes three separate exposure conditions based on topography. Exposure B is for an urban area with many obstructions for the wind. Exposure C is for open terrain with scattered obstructions for the wind and water surfaces in hurricane prone areas. Exposure D is for flat, unobstructed areas and water surfaces not in hurricane-prone areas. As an example, an urban area with obstructions affecting how the wind reacts with the walls and roof of a building (Exposure B) yields a lower wind-design pressure than a coastal region with no obstructions affecting the wind’s force (Exposure D). Let’s consider how wind pressures vary according to the location of a building. A 4:12 school roof (Category III) in an urban area (Exposure B) of Winston-Salem would be designed for a maximum corner (Zone 3) load of about 40 psf while the same-shaped school roof located in Wilmington and exposed directly to the open coast (Exposure C) produces design load pressures of about 100 psf, an increase of approximately 250 percent.

MATERIAL DESIGN

Now that we understand how to determine the correct wind-pressure design, we need a roof system that will adequately resist the design pressure. Within all building codes a description exists of most roof systems available and how the code allows the designer to rate these systems with respect to load resistance.

For example, according to IBC, a structural metal roof system permits a designer to use a UL 580 test or ASTM E 1592 test. Because a UL 580 test is a pass/fail test with the magnitude of the test variable(UL-15, UL-30, UL-60 and UL-90), no actual design data can be extrapolated to perform the necessary structural comparisons with the design pressures derived from the ASCE 7 evaluation. Therefore, the use of an accredited laboratory’s ASTM E 1592 testing results for a particular metal panel system is the only way to determine proper engineering data for use in the structural calculations while meeting the requirements of the IBC code wording.

The same critical analysis for other roofing materials is necessary to determine what testing, calculations or charts can be used to determine a certain roof system’s capacity to resist wind pressure and still satisfy the requirements of the IBC and any particular local code requirements.

METAL ROOF EXAMPLES

In 1996, Hurricane Fran hit land at Topsail Beach, N.C., with winds between 110 and 120 mph. Two metal roofs stood in its path. Topsail High School (Duplin County Schools) had just received a metal roof retrofit over a flat built-up roof and was designed to withstand a 110-mph wind, which was the current design wind speed per code at that time. The only damage the facility received was one section of rake trim was blown away. Topsail High School housed the Red Cross rescue mission during the aftermath of this storm.

Less than 100 yards from Topsail High School was a kindergarten facility with a metal roof. It was designed properly but not installed as designed. The hurricane pulled the roof up from the eaves toward the ridge, completely destroying the roof and all the building’s contents. A new metal roof was installed on the same structure—this time per the structural design—and the roof has withstood several wind events close to the magnitude of Fran since.

Recent tornadoes in eastern North Carolina produced structural devastation never before witnessed in that area. However, after a personal survey of all school districts in the area turned up no indications of metal roofs that had been structurally damaged, I contacted several of the major metal roof suppliers in the area. As my survey indicated, these suppliers did not have any indication of any particular metal roofs on school structures that had been structurally damaged by the winds. Although this is not a statistically accurate analysis, it certainly indicates that metal roofs on schools, which require a licensed design professional and a building permit, can withstand wind pressures that exceed the building code.

FINAL THOUGHTS

A design professional should prepare a structural design for all roofs—not some, but all roofs. Then a roof system should be selected that can resist the design pressures. Finally, the selected roof system should be structurally installed per the engineered design requirements. It really is that simple.

Chuck Howard is president of Metal Roof Consultants Inc., Cary, N.C., a member of Carolinas Roofing’s editorial advisory board. Since 1973, he has been involved with the design and/or installation of approximately 30 million square feet of structural metal roofs throughout North America. Licensed as a professional engineer in 12 states, he has provided his services to design, construct, consult or defend metal roofs in the field or in the courtroom. He can be reached at chuck@metalroofconsultants.net or at (919)465-1782.

Top Metal Roofers of 2010 Announced!

The 2011 Top Metal Roofers Face the Same Economic Struggles the Rest of the Metal Construction Industry Battles

**Story courtesy Metal Construction News**

With the steady rhythm of a deadfall hammer, our economy staggers along. And the 2011 class of the Metal Construction News Top Metal Roofers reflects the uncertainty of the construction market and the surviving nature of our top metal roofing contractors.

AARA Metals-Finish PictureClearly, total installed square footage of roofing has declined in the last few years as projects dry up and competition for the remaining work has become fiercer. When we surveyed our Top Metal Roofers, we did find bright spots-new beats that portray a faster pace in some areas as well as indicate potential increases in market share.

The roofers on the 2011 MCN list of Top Metal Roofers are surviving because more than half of their business is coming from retrofit work. It doesn’t matter whether they work primarily in the residential or nonresidential arena, these contractors are looking for opportunity on existing buildings. Of course, that makes sense given the incidence of new construction has crawled to a slow pace as both company incomes and municipal tax revenues shrink. Add to that a tight capital market and investment in new construction-residential and nonresidential-has faltered.

The business for these players is moving in the right direction, though. About 75 percent of our surveyed roofers say 2011 is shaping up to be better than 2010, and a somewhat smaller group indicates they are experiencing significant (more than 20 percent) growth.

That growth-or lack of growth-seems to belie the changing nature of the projects themselves. We asked how much the average project size has increased or declined in the last two years, and our roofers seemed evenly split. About half reported an increase in average project size, while half a decline. Those that experienced increases, reported modest (less than 20 percent) increases. Those that experienced declines in average project size, reported significant (more than 20 percent) declines.

What we found interesting in our survey, though, was what roofers revealed when we asked about the challenges they face in business today. We offered seven choices: controlling costs, developing leads, closing sales, increased regulations, increased tax burdens, low-cost competitors, and other. With clear distinction, the group chose controlling costs and low-cost competitors as the biggest challenges they face. The remaining selections grouped closely together.

In an environment of drastically reduced sales, the ability to generate leads and close sales fell second to our business owners’ struggles to control their costs. And when they do see opportunity on the sales side, they’re facing competitors who are undercutting price, perhaps sacrificing a professional margin through lack of business acumen or discounting just to get the job.

The survey reflected some optimism about the last years in construction, though. We asked our Top Metal Roofers what product or technology changes had made the biggest difference in their business during the last years? Their answers? Electronic plan rooms. More sophisticated estimating software, cool roof technology, and rollformer equipment advancements.

Perhaps those technology changes will make our recovery from a tough economic climate easier and more profitable.

2010 Top Metal Roofers

1. A-Lert Roof Systems,

  • A Division of Centurion Industries Inc.,
  • New Braunfels, Texas
  • Founded: 1975
  • 2010 Square Footage: 1,507,239
  • 2009 Square Footage: 1,902,456
  • 2010 Tonnage: 2,309
  • 2009 Tonnage: 2,912

2. Advanced Metal Roofing,

  • Wilmington, N.C.
  • Founded: 1994
  • 2010 Square Footage: 1,217,025
  • 2009 Square Footage: 1,354,302
  • 2010 Tonnage: 402
  • 2009 Tonnage: 444
  • Roofing Manufacturer Affiliation: Metalman Roofing Systems

3. Champion Metal Inc.

  • Stockbridge, Ga.
  • Founded: 2008
  • 2010 Square Footage: 565,000
  • 2009 Square Footage: 650,000
  • Roofing Manufacturer Affiliation: Fabral

4. Cincinnati Commercial Contracting,

  • Cincinnati
  • Founded: 1979
  • 2010 Square Footage: 229,480
  • 2009 Square Footage: 276,675
  • 2010 Tonnage: 532
  • 2009 Tonnage: 300
  • Roofing Manufacturer Affiliation: Butler Manufacturing

5. AARA Construction Inc.

  • Phoenix
  • Founded: 1976
  • 2010 Square Footage: 227,518
  • 2009 Square Footage: 244,845
  • 2010 Tonnage: 176.32
  • 2009 Tonnage: 189.76
  • Roofing Manufacturer Affiliation: Ultra Seam Inc.

6. The Sheridan Corp.

  • Fairfield, Maine
  • Founded: 1947
  • 2010 Square Footage: 194,509
  • 2009 Square Footage: 69,443

7. Crossland Construction Co. Inc.

  • Columbus, Kan.
  • Founded: 1978
  • 2010 Square Footage: 187,456
  • 2010 Tonnage: 141

8. Septagon Industries,

  • Sedalia, Mo.
  • Founded: 1980
  • 2010 Square Footage: 159,886
  • 2009 Square Footage: 75,602
  • 2010 Tonnage: 170
  • 2009 Tonnage: 81
  • Roofing Manufacturer Affiliation: Butler
  • Manufacturing, BlueScope

9. LaFave’s Construction Co. Inc.,

  • Landis, N.C.
  • Founded: 1982
  • 2010 Square Footage: 137,600
  • 2009 Square Footage: 166,500
  • 2010 Tonnage: 115.4
  • 2009 Tonnage: 128.6
  • Roofing Manufacturer Affiliation: MBCI, McElroy Metals

10. Coleman Adams Construction Inc.,

  • Forest, Va.
  • Founded: 1971
  • 2010 Square Footage: 30,000
  • 2009 Square Footage: 56,200
  • 2010 Tonnage: 51
  • 2009 Tonnage: 21

11. Hansel Construction Services LLC,

  • Parkersburg, Iowa
  • Founded: 1994
  • 2010 Square Footage: 14,000
  • 2009 Square Footage: 11,000
  • Roofing Manufacturer Affiliation: Wheeling
  • Corrugating

12. Scudder Roofing Co.,

  • Marina, Calif.
  • Founded: 1982
  • 2010 Square Footage: 8,400
  • 2009 Square Footage: 52,800

13. All-Spec Metal Systems LLC,

  • Holts Summit, Mo.
  • Founded: 1997
  • 2010 Square Footage: N/A
  • 2010 Tonnage: 89.98
  • 2009 Tonnage: 129.42
  • Roofing Manufacturer Affiliation: Various manufacturers

Metal Roofs vs. Weather: Retrofit Metal Roofs Hold Up on North Carolina Schools

My granddad had a barn with a red metal roof. When I was a kid, many years ago, I remember being in this barn when it rained. The sound was melodic and would almost put you to sleep. I never saw granddad patch this roof. I never saw him replace this roof. When it rained, the roof kept the hay dry. Life was simple then.

We are now in the21st century, and granddad’s barn has been gone since the middle 1980s. But I think we can still capture the magic of that old roof today. It is possible to recreate the simplicity and efficiency of that sloped metal roof for our public buildings, especially our public schools. Let’s look at a few examples of how sloped metal roofs were successfully used in the school retrofit market— not only keeping out rain and snow but holding tight during high-wind events.

North Windy Ridge Elementary School
North Windy Ridge Elementary School is located in Buncombe County. When the school was built, a metal roof was specified. Unfortunately, the roofing process was not completed properly—shop drawings were not followed—and the metal roof had persistent leaks. After a lawsuit was filed against the original roofing contractor in 2008, the school board hired an engineer to produce a set of engineering plans and specifications necessary to re-cover the original 100,000-square-foot metal roof with a new metal roof. Dick Canon with Canon Consulting & Engineering, Moore, S.C., prepared a set of bid documents that utilized a structural framing member from Odessa, Fla.-based Roof Hugger Inc. placed directly over the existing metal roof. The new metal panel system attached to this framing system was supplied by MBCI, Houston. The cavity between the two roofs was adequately ventilated to eliminate the possibility of condensation within this space. After being constructed per the contract documents and being monitored for conformance with these documents throughout the project, the owner had the metal roof it had originally expected. This retrofit metal roof has been leak-free during the turbulent winds and excessive snow loads experienced by all roofs in mountainous regions since its installation in 2009.

North Lincoln High School
A project similar to the North Windy Ridge project was bid and completed in 2010 for the North Lincoln High School facility, Lincoln County, N.C. The original metal roof had not been installed per shop drawings and had faulty workmanship. Instead of abandoning the use of a metal roof, the owner hired Canon Consulting & Engineering to provide a set of contract documents necessary for bidding. Again, Dick Canon specified a Roof Hugger structural system placed directly over the existing metal roof as a substrate for a new standing-seam metal
roof system from MBCI. Darrell Gettys, North Lincoln High School’s maintenance director, reported at the November 2010 board meeting that the school finally had the metal roof it originally anticipated: The 221,000-square-foot facility has experienced no leaks since it was installed more than one year ago. The strong winds spawned from severe thunderstorms and sporadic tornadoes seen in the spring of 2011 swirled by this facility with no damage to the new structural retrofit metal roof. I should note there was nothing wrong with the original design, contract documents or materials for these projects that would have required replacing the original panels. Unfortunately, in both cases the culprit was lack of attention to the installation details and procedures. Like all other roof systems, a proper design must be matched with proper installation and inspections throughout the project.

Davidson County Schools
In spring 2010, Davidson County Schools received bids for its 19th, 20th and 21st metal retrofit roofs. These three roofs total more than 135,000 square feet. The school system’s first metal retrofit roof was installed in 1989, and more than 1 million square feet of retrofit metal roofs have been installed since then. All except two of these roofs have utilized a lightgauge framing system that created a minimum of 1/2:12 slope over an existing flat roof. The three projects bid together in 2010 were for Midway Elementary School, Lexington, N.C.; Welcome Elementary School, Lexington; and Stoner-Thomas Elementary School, Lexington, and were engineered by Bilger Engineering, Raleigh, N.C. The roofing contractor was LaFave’s Construction Co. Inc., Landis, N.C. LaFave’s Construction has performed the majority of the retrofit work for Davidson County Schools since 2004. With the retrofit framing and roofing approach, a flat roof with a top membrane that had deteriorated with exposure to the exterior elements is replaced with a metal roof panel that is expected to last more than 45 years. In addition, because the metal roof requires positive drainage created by the sloped sub-framing, any water on the roof immediately is forced off of the roof at perimeters. Davidson County now has three more retrofit metal roofs that will provide the same structural resistance to wind loads and weather barrier to the elements. Like my granddad’s barn, water off of the roof can’t get into the hay.

Mabel Elementary School
The final example of a successful retrofit metal roof application is the addition of a light-gauge framing system over a sloped shingled roof, which then was covered with a metal roof panel system. This approach was used for Mabel Elementary School, Watauga County, N.C. At this school, shingles were installed when the building was built, approximately 18 years earlier. The 54,000-square-foot roof had multiple intersections, hips, valleys and ridges that made it difficult to get the shingles to seal. In addition, the school sits on top of one of the highest areas of the Appalachian Mountains and receives significant snow starting in late October and lasting until early April each year. These factors had caused the shingled roof system to leak for most of the years of its existence. Attaching a 4-inch steel purlin system directly to the existing roof joists created an acceptable platform for a standing seam metal roof to be installed. An additional 6 inches of unfaced fiberglass insulation was placed between the two roofs adding an R-value of 19 to the existing roof’s R-value. The design work was performed by Metal Roof Consultants Inc., Cary, N.C., with contracting work completed by Lafave’s Construction. Work was finished in late October 2010, and the first snowfall occurred a few days later. The roof resisted the onslaught of several feet of snow and the spring thaw without a leak for the first time since the school was constructed. It hopefully did not put the kids to but it sure kept the “hay” dry!

Retrofit Simplicity
Although retrofit metal roofing may sound complicated, it is based on simple concepts which can yield a roof that will last as long as the brick in the walls and the concrete in the floors. This simplicity allows the engineer to be able to depend on structurally sound information concerning wind loading and live loading, as well as code and industry accepted metal roof systems’ structural capacities, on which
to base the design. In addition there are time-tested installation principles on which the professional contractor can depend. When put together to satisfy a school’s need to replace an existing roof, they can create a roof with a low life-cycle cost. My granddad had an eighth-grade education but he understood the benefits associated with a sloped metal roof and built his barn using this type of roof more than 90 years ago. The same basic principles—creating slope to get the water off the roof and using a metal roof material that will last many years—are used today to satisfy the needs of our public school systems throughout the country and especially in the Carolinas. I wonder whether granddad knew that what he determined to be the best roofing choice to keep his hay dry would be used extensively by school districts to do the same for our next generation.

Chuck Howard is president of Metal Roof Consultants Inc., Cary, N.C., and a member of Carolinas Roofing’s editorial advisory board. Licensed as a professional engineer in 12 states, he has provided his services to design, construct, consult or defend metal roofs in the field or in the courtroom. He can be reached at chuck@metalroofconsultants.net, www.metalroofconsultants.net or (919) 465-1782.

Retrofit by Raising The Roof

Winchester is located in eastern Indiana, close to the Ohio border. It is a farming and light manufacturing area where the same families have lived for generations. It is a proud community, where people go to church together, help each other in times of need, and go to high school sports and band competitions with passion and pride that transcends gender and politics.  It is the kind of community where everybody knows everyone else, and fundamental values and differences are few. A flat and leaking roof at the high school made an impact that split this quiet community and caused actions and words that have seldom been witnessed before.

During 2007 it became obvious that another patch on the classroom wing of the high school was again failing.  The students and teachers were coexisting in an interior environment that was wet, humid, and had a very distinctive and repulsive smell.  The school board, working hard to solve this problem, solicited advice from a conventional roof trade association that works primarily with flat roofs, and an architectural firm that also specialized in flat roof work.  In January 2008, the have seldom been witnessed before.

During 2007 it became obvious that another patch on the classroom wing of the high school was again failing. The students and teachers were coexisting in an interior environment that was wet, humid and had a very distinctive and repulsive smell. The school board, working hard to solve this problem, solicited advice from a conventional roof trade association that works primarily with flat roofs, and an architectural firm that also specialized in flat roof work. In January 2008, the board elected to proceed with the architectural firm to design and have constructed another flat roof on the high school. That decision did not sit well with many in the community. Further research by the school board uncovered the possibility of constructing a slight slope over the existing flat roof and adding a metal standing seam roof system. This possibility was introduced at the February board meeting, which started a heated debate, pitting proponents of flat roof retrofit against sloped metal retrofit. It was quoted in the local paper, The News Gazettethat “each side accused the other of only hearing what they want to hear …” By the time the March meeting came around, there had been a protest by the students refusing to occupy the classroom wing due to the leaks and smell, and, as reported by The News Gazette, “approximately 200 parents and students” attended the board meeting because “they were angry over the roof.” By the end of the meeting the architect hired to provide the flat roof design had left the meeting and indicated that he did not wish to proceed with such a contract.

On March 31, 2008 Metal Roof Consultants was asked to attend a special board meeting to present a sloped metal retrofit roof alternative for the school’s roof woes. A visit to the site generated information and pictures for a PowerPoint presentation. This presentation, concerning a metal retrofit roof possibility, was presented to approximately 100 parents, teachers, students and, of course, board members. The concept of not removing the old roof, but allowing it to dry out naturally in the dry and vented cavity created by the metal retrofit process made common sense to those in attendance. There had not been time to “dazzle” those in attendance with technical facts about the structural characteristics of this system, the many colors they had to choose from or the massive energy benefits inherent with this type of roof system. However, they did hear about a concept that would allow them to permanently solve their continuing roof problems with a tried and true system that would probably be the last roof for this building. All in attendance, including the board members, applauded after the presentation as a sign of relief they could finally all agree upon a positive direction for a permanent solution to Winchester high school’s roof. MRC was awarded a contract to prepare the design, drawings and specifications for such a roof and procure bids for its construction. The community was united and at peace again.

Dr. Greg Hinshaw assumed his responsibilities as the new superintendent of the school system on July 1, 2008. He inherited a commitment to proceed with putting a sloped metal retrofit roof on the high school, but no money for construction. Through his diligent efforts, loan money was procured from the state of Indiana, and the project was bid in September 2008. The low bidder was Smarrelli Construction of Richmond, Ind., and MBCI was approved as the supplier of the metal materials required for the 108,000 SF project. MBCI provided the final design and material package; using their NuRoof system and BattenLok HS roof panels. The contract price was approximately $1.6 million, which was slightly less than the original architect’s estimate for the removal and replacement of the existing flat roof system with another flat roof system. Work began in December 2008 and was finished in October 2009.

The retrofit metal roofing system consisted of leaving the existing roof in place, which allowed school to continue while the new roofing system was installed. It also eliminated the need to remove the existing roof, with the need to dump these used materials in the local landfill. It has been estimated that approximately 15 percent of all landfill materials consists of non-recyclable roofing materials. With the metal alternative, these materials remain in place, thereby being kind to our environment. In addition to leaving these materials, 6 inches of un-faced fiberglass insulation was installed directly over the existing roof. This material not only raised the insulating value of the roof by approximately 640 percent (R-3.5 to R-22.5), thus saving energy costs, it allowed the existing roof to “breathe” and release its moisture content through the glass insulation into the ventilated air in the new roof cavity and expelled from the cavity through vents at the high sides of the roofs. The new roof panel, even though painted a bronze color, utilized Energy Star paint additives that created a “cool roof” reflecting approximately 80 percent of the solar heat back into the atmosphere and not into the building. All of these benefits of the metal roof make this roof an extremely “green” roof, reducing the carbon footprint of the building and saving precious energy dollars.

In addition to the energy benefits of the metal retrofit roof, the materials should last the remaining lifetime of the school building. The painted roof system, while guaranteed for 20 years, should provide 50 to 60 years of service with no maintenance other that checking the roof periodically to insure that no external damage (tree limbs, ice damage, etc.) has occurred. And of course, since metal is not negatively affected by ultraviolet rays, the metal surface will not break down from the suns affect. And, of course, the new metal retrofit roof does not leak! It is guaranteed for a minimum of 20 years to not leak. Since the materials will last much longer, the guarantee period is merely the beginning of the time the school system should expect the roof to provide protection.

What do the superintendent, Dr. Hinshaw and principal Tom Osborn, have to say about their metal retrofit roof experience?

Tom Osborn, Principal of Winchester High School: “In the spring of 2008 the flat roof of our 42-year-old building suffered substantial problems. Leaks became overwhelming. The roof on the section of the building that houses the academic programs failed to the extent that several halls were lined with trash cans to catch the constant drips caused by spring rains and the thawing of ice and snow. As the roof and ceiling became saturated, the humidity level grew inside the building. Students were relocated to other rooms as another cold patch was applied to stop the water penetration. There was serious doubt, however, about whether any amount of repair work could save the roof and whether the old roof would ever dry out even if it could be made waterproof again.

Metal Roof Consultants was hired to lead the school corporation through the process of installing a standing seam metal roof later that spring. Construction progress was steady throughout the 2008-2009 school year. MRC; the general contractor, Smarrelli’s of Richmond, IN; and the staff of Randolph Central worked together in a cooperative collegial manner. MRC provided us with a design that is attractive as well as weather tight. The ventilation system helped quickly dry out the old roof even to the point that extra insulation has been added to the attic cavity to help the HVAC system. Our 42-year-old building now has a professional new appearance that has helped return pride in our facility to the community, staff and students. There is new feeling of optimism and Randolph Central again has a building that we believe can safely and efficiently serve the youth of our schools for many years to come. I can sincerely say the final product has far exceeded the expectations of anyone who was here at WCHS in March of 2008! We are very pleased with our decision to undertake this project and install a standing seam roof.”

Gregory P. Hinshaw, Superintendent of Schools, Randolph Central School Corp.: “The need for roof replacement at Winchester Community High School was, by far, the most pressing issue when I became superintendent in the summer of 2008. Fortunately, the school board had already employed Metal Roof Consultants to engineer a new roof and construction began in the fall. The new roof has totally changed the exterior appearance of the building and our students, faculty and public have all been very supportive of the process. The retrofit roof has improved the appearance, environment and energy management of the building. We are very pleased with the project.”

Metal retrofit roofing has restored the peace in Winchester, Ind. Through diligent efforts by the all involved in the school system, they now have an attractive, energy efficient and long lasting roof system that will continue to serve their district for many decades to come.

Now they can get back to academics, church, sports, band………

 

Retrofit: Do it Right The First Time

When John Martindale, President of Brothers Services Company, Baltimore, Md., wanted to expand his market in the local area, he looked into the commercial metal retrofit market. Having been a very successful and large residential contractor for years, he felt he needed to diversify into this market.

His first step was to attend the 2003 METALCON International convention held in Tampa, Fla. He attended a seminar that described the basics of the metal retrofit roof market. I was fortunate to be presenting this seminar and even more fortunate to meet John after the seminar, which led to an ongoing professional relationship. It was obvious from the start of this relationship he was acutely interested in entering this attractive market in a manner that would make sure Brothers would “do it right the first time.”

While not every step has been totally flawless the first time, his insistence on making the customer’s finished product right the first time has always prevailed. Their most recent finished project, Orleans Court Condominiums, located in Ocean City, Md., is a prime example of this philosophy and is the example to be used to demonstrate how there is really only one way to construct a metal retrofit roof: “Do it right the first time.”

School re-roofing

This story starts at the Virginia School Board Convention in November 2006. A school board member, like most do, proclaimed he did not understand why school roofs were designed and constructed with a predominately flat profile. His opinion was that to re-roof a flat roof, without adding pitch and a metal roof, was a travesty and their school board was determined not to allow that to continue. He asked us to contact Blake Giddens at Restoration Engineering, Inc., since his firm provided most of the roof engineering services to their district. That contact yielded no positive information about an upcoming school project, but, instead, an interest in converting a flat roof on a condominium in Ocean City, Md., to a sloped, painted, aluminum roof. Blake indicated he was somewhat aware of the concept of adding slope to a flat roof, but was asking for whatever advise and suggestions we might have in order for him to provide a design that was “right the first time.” Of course he could have prepared a loosely put together specification, generic plan and hoped a contractor would be capable of filling in the design holes, but he, instead, was very receptive to engineering and detailing that was proven effective over time.

REI provided a full set of detailed plans and specifications that accurately depicted his expectation for the metal retrofit roof. Included in his specifications, was the requirement the contractor prepare a set of engineered shop drawings showing how his basic design concept would be satisfied by the contractor’s approach and materials. BSC was fortunate to be selected out of three bidders to construct the metal retrofit roof.

The bid stage was “done right” and yielded a competent contractor, skilled and experienced in metal retrofit roofing. After a proper contract was executed, the contractor began the design process.

Over the years everyone has seen good and bad attempts at providing shop drawings. The “bad” ones use standard details pasted together to yield a patch-work of drawings and details, none of which truly depict the actual conditions of the particular roof. The “good” ones actually measure the existing roof, perform wind design load calculations, perform fastener pull tests from the existing structural components and provide a set of scaled drawings and details that truly describe how the metal retrofit roof is to be applied to the existing flat roof.

The second approach is more time consuming and costly, but was the only way to “do it right the first time.” On this particular project, BSC knew this was the only way to proceed.

First the new roof needed to be properly designed. ASCE-7-05 was used to determine the wind speeds and corresponding wind uplift loads in all specific areas of the new metal roof. That is the critical foundation for any roof project, but, unfortunately, is one often given little importance. A mistake here could have devastating effects in the future. Need I say: “Do it right the first time?”

During the design process, materials needed to be selected. The coastal environment called for an aluminum roof and galvanized steel sub-framing members. An Englert S2500 aluminum panel (.040-inch), with a Kynar-based paint system was selected to be placed on an MBCI, 16 gauge galvanized, sub-framing system. The ASTM E-1592 uplift tests for the Englert panel was obtained to determine where clip supports were necessary, then appropriate framing was designed to adequately transmit the wind design loads into the existing building structure.

Normally a light-gauge banding system would have been utilized to stabilize the new sloped roof structure, but 16 gauge angles were used instead to further add stiffness to the framing system which might have to withstand 120 mph coastal winds. In addition, the owner wished to add a 7-foot roof overhang over the decks of the top units, in order to provide shade. While the structural members were designed to cantilever over this space, exterior columns were added by agreement of the owner, REI, and BSC. This addition, was a little “belts & suspenders,” but assured all involved we would not ever have to worry about the coastal winds disturbing this condition. We didn’t want to come back later, but, rather, “do it right the first time.”

Now, some 14 months after that board member stop at the booth in Virginia, we had located a willing owner with a need, a very capable engineer to create a bid and contract package, a contractor willing to do the work for a set price and a finished design and needed materials selected. All that had to be done now is to put it all together!

The project was started on January 14, 2008 and completed June 20, 2008. An experienced subcontractor was retained to lead the construction activity, with BSC employees working with them to accomplish the needed work.
Critical to this process was BSC’s project manager, Phil Lisak. Although this was his first metal retrofit roof project of this complexity, Phil provided the necessary controls on material procurement and scheduling, as well as monitoring the progress of the work. This vital part of the construction puzzle is often overlooked. It is sometimes assumed a well designed project, with a qualified crew, will always produce a good final product. Unfortunately, metal roof construction is not that simple. Phil proved to be up to the many challenges associated with this job, including one of the most important: motivating the men to perform quality work. That required him to know what the shop drawings were depicting, as well as having the tenacity to make sure things were put where they were supposed to be.

At the same time, the men needed to be motivated to perform the work in an efficient and effective manner. The driving force for him was to get the roof components installed as they were designed and “do it right the first time.” With only a few minor exceptions, that was accomplished.

The majority of roof lawsuits in the metal roofing industry are caused by faulty installations. The main reason a project does not make the margins expected is attributed to faulty installations and a lot of re-work dollars spent. Phil did an excellent job of working with the men to ensure there was no faulty workmanship. And the final results: zero punch-list in late July after a walk-through with Blake Giddens! Great job, Phil.

Conclusion

In summary, there are eight major components that make up a well planned and executed metal retrofit roof project:

1. A building owner that understands the long term benefits of converting a flat roof that leaks into a sloped one that doesn’t.
2. A competent design professional providing a detailed set of bid and contract drawings.
3. An experienced metal roof contractor, with experience in metal retrofit roofing.
4. A set of engineered shop drawings based on ASCE 7-05 wind uplift calculations and ASTM E-1592 metal panel wind uplift testing provided by the contractor. These need to be prepared by a licensed professional engineer with experience in this area.
5. Materials which are appropriate for the specific design.
6. Installers who are well qualified in this type of work and who understand the concept portrayed in the shop drawings.
7. A project manager capable of motivating the work force to produce a quality product in a specified amount of time.
8. Most importantly, doing all of the above “right the first time.”

There you have it. From John Martindale wanting to make sure his company “did it right the first time” by attending METALCON in 2003, to his company insisting the Orleans Court Condominium project was designed and installed “right the first time.”

The metal retrofit roof market provides a great opportunity for companies like BSC that believe in this, but also provides great risks for those that do not. Make sure you are one of the contractors that are successful and “do it right the first time.”

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Metal Retrofit Roofing – A Solution in a Bad Economy

It was the spring of 1981 in southern Ohio. I had a small general contracting business that specialized in pre-engineered metal buildings. Interest rates were in the 15% range, new construction money was non-existent, and I had zero back-log for the summer season. Sound familiar with the current economic climate? Having been raised by parents that continually said, “Can’t never did anything”, I was not going to concede that my business couldn’t survive.

I remembered a project I had completed a year earlier where the customer insisted that I add a sloped metal roof over his existing flat roof. While it had never been done before, this building customer was insistent that he wanted the same roof that was on a building addition I had constructed for him. After saying no several times, I agreed to attempt to design and build such a roof. Well, it worked. As a matter of fact, it is still functioning in Wilmington, Ohio today, with nothing done to it over these 29 years.

Instead of spending my day telling whomever would listen how bad the economy was, I asked my wife to hand-type (sorry, no laptops and printers then) 100 one (1) page letters to past customers explaining how we had successfully converted a flat roof to a sloped roof for our Wilmington client. I then merely asked them if there might be any interest in considering such a roof conversion on any of their flat roofs. Twenty six (26) positive responses later I was firmly immersed into a new market of providing such conversions. “Can” prevailed again.

Now “fast-forward” to the present. The economy is in an even worse condition that in the early 1980’s, and new building construction has ground to a very slow crawl. The media is full of stories of failing companies, lay-offs, recession, etc. Bidding lists for new construction show dozens of companies willing to take the work at low or non-existent profit in order to “keep our people busy”. Not a very encouraging sight, is it?

Well, remember, “Can’t never did anything”. Take a page out of my desperation hand-book almost 30 years ago when I turned to retrofitting flat roofs with sloped metal roofs. While I have made a career in this market with over 15 million SF designed and/or constructed, it is still a very small market, ready to explode. While the exact numbers are difficult to verify, most sources indicate that the US roofing market is in the 40 billion SF range per year. Of that amount, replacement and repair has accounted for approximately 75% over the last 10 years. That yields approximately 30 billion SF of roofs that need major work in 2009. Unfortunately, I cannot find a reliable source that indicates how much of that work is projected to be covered with a new sloped metal roof. Even very global estimates show this work at less than 5%, and I suspect it is much lower than that. But…..that is a good thing for an aggressive and passionate contractor!

In addition to the “adding pitch” approach, in 1991 an engineered system to cover existing metal roofs with new metal roofs was developed by a friend of mine, Red McConnohie, called Roof Hugger. This engineered system of covering even old metal roofs, added to my company’s ability to service the existing roof market of replacement and repair. Now I had two (2) bullets in my gun. Let’s look at each of these bullets separately:

Add slope to a flat roof
a. Concept – This concept allows a flat, or near flat roof, to have a slope added and a new metal standing seam roof applied. Attaching base clips or supports to the existing building’s structure is performed to transfer the roof loads properly into the structure, most time without having to remove the existing flat roof. Then a variable height steel column is attached to actually create the needed slope (only ¼” per foot is required for most metal covering warranties). A steel purlin is attached to the top of the column on which to attach the new metal roof. Think of it as a small metal building sitting on the original roof. Needless to say, these materials and the attachment to the existing structure require the services of a professional engineer licensed in the state where the work will be performed. All things listed above are currently available today to any contractor.

b. Marketing – Marketing this concept is actually very simple. Merriam-Webster online dictionary defines marketing as “to expose for sale in a market”. The following is what you have to expose:

  • The market consists of building owners that have flat roofs. Schools, manufacturing, municipal and state, and the federal government have billions of SF of flat roofs that need a sloped roof conversion. Such a conversion will pay for the cost of the roof, due to energy and lack of required flat roof maintenance, within 10 to 15 years. Can you sell a FREE roof?
  • In today’s market, the initial cost of a sloped metal roof system is, in most cases, less than removing a flat roof and replacing it with a BUR of Modified Bitumen Roof with tapered insulation. Tapered insulation is required by most code authorities to achieve a certain level of roof slope.
  • The components of the framing system, roof panels, and trim are made from recycled materials and are themselves over 80% recyclable. In today’s world of providing “green” products and systems, a sloped metal roof is as green as green gets.

B. Recover an existing metal roof
a. Concept – This concept allows an existing metal roof to be recovered with a new metal roof, without the cost and hassle of removing the original roof. A light gage structural member, notched to span over the original roof ribs/corrugations, is located directly over the building’s framing system. This member is attached to the roof purlins through the bottom flange of the member and the existing roof sheet. Now a new standing seam metal roof is attached to this new member. As with the adding pitch concept, a professional engineer needs to be retained to determine the required structural conditions. In addition to allowing for the installation of a new metal roof, the cavity between the two roofs can be used to add insulation to the building envelope.
b. Marketing – Marketing this concept, again, is similar to the adding pitch concept. The following is what needs to be exposed to potential customers:

  • The metal buildings built in the 1950’s through 1970’s predominately used through fastener roof attachments. Especially for the larger industrial and warehouse roofs, the expansion and contraction of the metal roofs either loosened the screws or elongated the holes made by the screws. Both scenarios allowed water to run down the threads of the screws and into the building. Therefore, look in the industrial parks that were constructed during that time frame for a large source of potential work.
  • This concept allows the existing roof to remain, therefore the activity inside is undisturbed.
  • The possibility of insulation being added to these buildings, that had minimal insulation installed initially, can allow the retrofit process to pay for itself quickly.
  • In today’s, market both older and more recent metal roofs are found to not meet the current code requirements for wind uplift. For metal roofs installed on pre-engineered buildings, the standard 5’-0” purlin spacing often will not satisfy panel clip spacing requirements in edge and corner conditions (refer to ASCE 7 for uplift load calculations and ASTM E-1592 for proper panel testing). In metal roofs installed over solid metal decks, the location of the panel clips is many times incorrect with respect to the uplift loads and panel capacities. Placing the new structural member properly, after proper design by a licensed engineer, can correct these deficiencies without the removal of the existing roof.
  • Of course, adding insulation to an existing roof immediately decreases the buildings energy consumption and is a direct benefit to the building owner.

The above advantages of a retrofit metal roof were not available to me in 1981. Yet, I, a small contractor who graduated in the part of my college engineering class that made the top ½ possible, proposed such a solution to 100 building owners , launching myself into a productive and profitable career that has not yet seen even a glimpse of the potential of this market. My father has proven to me that a double negative is in fact positive…..Can’t never did anything. So, convince yourself that you CAN expose building owners to the benefits of retrofit metal roofs, and watch your business grow, in any economic climate.

The Basics of Metal Roofing

Like any other elements that make up a building exterior envelope, a metal roof has several basic elements that, when designed and installed properly, will provide a building with a roof surface that will yield decades of satisfactory service. These basics hold true for both new metal roofs and retrofit metal roofs. On the other hand, if the basics are not adhered to, the finished metal roof system will provide only marginal service. An architect, engineer, or consultant, knowing these basics and making sure they are incorporated into metal roofing projects, insures that the building owner is getting a roof system that will last well beyond its warranty terms.

A metal roof is a functional element of a building that has certain wind load resistance responsibilities. It is certainly responsible for protecting the interior contents from the exterior atmospheric elements, but it has to have the capacity to remain in place to provide this protection. As has been evidenced by the effects of hurricanes, tornadoes, and the like, their capacity to withstand such devastating forces is unsurpassed in the roofing industry. The reality is that a metal roof’s capacity to withstand these extreme loads is dependent upon the metal roof being properly designed as well as installed per the contract documents. Let’s discuss how the basic elements can have a positive effect on a metal roof system.

First, it must be noted that a locally licensed professional engineer must be retained to produce the actual structural design work associated with the roof. This work must be compatible with the building’s main str4uctural design. That does not mean that if the consultant is not a licensed engineer he or she does not need to understand the design basics. A metal roof consultant needs to be able to understand the professional design results in order to be effective in his or her capacity on a metal roof project. The main design elements for a metal roof are, 1) using the proper documents to determine the expected wind loads throughout the roof area and, 2) choosing the proper metal roof products to resist these loads.

In most areas, the effects of uplift wind pressure on different portions of the installed roof surface are the most severe roof loads to consider. The American Society of Civil Engineers (ASCE) has a publication that is accepted in the International Building Code (IBC) as the standard for determining these loads. The IBC is almost uniformly accepted by all states. The publication, ASCE – 7- Minimum Design Loads for Buildings and Other Structures, clearly defines how to determine the various zones on the roof that have different design loads, along with the actual loads for those respective areas. Chapter 6, Wind Loads, goes into great depth to show what wind speeds should be used, depending on the geographic location of the building. It also provides information necessary to determine the dimensions and locations of the various wind zone areas within the plane of the roof. In addition, there are several variables that impose increasing factors and decreasing factors to the design load based on parameters such as surrounding topography, occupancy of the building, building height, etc. All of these factors need to be understood and considered when determining the required wind loads for a metal roof.

After the proper loads are determined for all zones of the roof, a metal roof system must be analyzed to determine how it can resist these loads. The American Standard for Testing and Materials (ASTM) has developed a pressure testing procedure commonly referred to as an “air bag test”. This procedure applies uniform pressure from the bottom of the panel surface by introducing air into an airtight chamber and allowing pressure to form on the bottom of the panel. This pressure produces forces on the panel that simulate actual wind pressure forces that would be introduced onto the panel system when wind blows over the roof. The actual procedure is labeled as an ASTM E-1592 test and yields ultimate load forces that the panel and its attachment components can withstand. Needless to say, the spacing of the attachment components greatly determines the capacity of the engineered metal roof system. The spacing of these attachment points, and the associated allowable load capacity, are shown within the report.

The use of the ASCE – 7 design loads and the ASTM E-1592 metal panel system capacity will properly determine under what conditions a panel system can be used to resist the design loads for a particular roof. These methods should always be incorporated in any metal roof design to insure that the proper metal roof system, along with the proper attachment method, is used.

In addition to the structural evaluation required to determine what materials and associated panel assemblies can be used for the metal roof, there are other, non-structural, basics to evaluate. Some of the most important are as follows:

Drainage
Every metal roof must have positive drainage to eliminate the possibility of ponding water on the roof surface. This slope (as little as ½” in 12” for structural standing seam panel systems) directs water to the building’s perimeter or internal gutter. The size of the guttering system, location of outlets, size of outlets, distribution of the water when it is introduced to the surrounding areas, etc. need to be taken into consideration when determining the proper performance of a metal roof system. Most metal roof panel manufacturers have design information about their gutter and downspout system’s capacity, and all building codes identify the amount of rain in a specific time-frame that is required to be accommodated. Make sure that these resources are utilized when determining how to accommodate run-off drainage.

Flashings and curbs
For the metal roof system to be useful for the building owner, it must not only remain structurally sound during design loading conditions, but also remain watertight. After all, that is why we need roofs! For that to be accomplished, the flashings that seal the roof to the eaves, ridges, walls, etc. must be designed to withstand water intrusion. They must also be designed to accommodate the forces of thermal movement. Additionally, curbs must be integrated into the roof system in such a manner that they, too, will resist water penetration as the panel is transferring collected water to a lower location such as a gutter or exposed eave. Like the roof flashings, curbs must take panel expansion and contraction into account. As with the drainage design, the metal panel manufacturer will have standard details showing how their total roof system should be flashed and curbed. While this standard information is available, the consultant/designer is responsible for determining the particular requirements of each roof, and modifying the standard details to suit.

Insulation and condensation control
With the design and installation of every metal roof there is possibility of incorporating thermal insulation under the metal roof panel. The main purpose for this material is to separate the exterior temperatures from the building interior temperatures. Some basic design points are as follows:
• When a vapor barrier is required (and it is in all but a few cases), place it on the “warm” side of the insulation. Make sure the vapor barrier is sealed properly in the field application to prohibit interior air from coming into contact with the exterior metal skin, forming condensation.
• Fill all voids between the top of the insulation and the bottom of the metal panel with insulation. That includes the voids created at the ridge and hips. Left un-insulated, these areas are prone to condensation formation. If the voids cannot be completely filled, the cavity must be vented on the “cold” side of the insulation with outside air. Air exchange in any given cavity of 3 to 5 times per hour is required to control condensation in most conditions.
• More insulation is not necessarily better. Usually after an R value of approximately 20 is attained, the return on investment of more insulation decreases quickly. Do not think that “If 6” of insulation is good, 12” is twice as good”. Do the thermal and associated expected energy consumption calculations, using the most current ASHRAE procedures, and use the most efficient amount of insulation.
• Insure that the proper insulation and vapor barrier are used for the actual conditions. Consult with the metal panel manufacturer to insure that either product will not negatively affect the panel or its components.

In addition to reviewing the basics discussed in this article for every metal roof project, it is imperative that documentation of the final design determinations be properly prepared. That requires that a scaled shop drawing, complete with large scale details for every flashing condition incorporated in the project, be prepared by the contractor and/or manufacturer and reviewed by the consultant/engineer to insure that the proposed metal roof system meets the expectations of the design documents. During this review process the consultant/engineer and contractor need to be extremely candid in expressing their expectations, thus eliminating costly arguments after installation has begun.

Last but certainly not least to consider is how the metal roof is installed. Installation errors are by far the leading source of law suits for metal roofs. While this phase of the project is often times relegated to minimal attention by “junior” staff, it is the most important phase of any metal roof project. Making sure that the contractor knows that the installation of the roof will be closely observed to insure that the finished product meets or exceeds the level of detail indicated in the approved shop drawings sets the stage for a very successful metal roof project. As a consultant, establish this understanding early in the schedule and maintain its diligence throughout the entire project. It will yield positive dividends for all parties involved.

The bare basics of metal roofing have been introduced in this article. Each of the listed basics deserves further explanation and research by the consultant serious about providing related services to a building owner. As with all areas of building envelope study, the basics of metal roofing need to be explored exhaustively in order to provide excellent advice on a metal roofing project. Take the basics described in this article as a foundation from which to build a greater understanding of the proper design and installation for a metal roof system that will perform properly.

Plan a Well Executed Metal Retrofit Project

When John Martindale, President of Brothers Services Company (BSC), Baltimore, MD wanted to expand his market in the local area, he looked into the commercial metal retrofit market. Having been a very successful and large residential contractor for years, he felt he needed to diversify into this market. His first step was to attend the 2003 METALCON International convention held in Tampa, FL. He attended a seminar that described the basics of the metal retrofit roof market. I was fortunate to be presenting this seminar and even more fortunate to meet John after the seminar, which led to an ongoing professional relationship. It was obvious from the start of this relationship that he was acutely interested in entering this attractive market in a manner that would make sure that Brothers would “do it right the first time”. While not every step has been totally flawless the first time, his insistence on making the customer’s finished product right the first time has always prevailed. Their most recent finished project, Orleans Court Condominiums, located in Ocean City, Maryland, is a prime example of this philosophy, and is the example to be used to demonstrate how there is really only one (1) way to construct a metal retrofit roof….”Do it right the first time”.

This story starts at the Virginia School Board Convention in November 2006. A school board member, like most do, proclaimed that he did not understand why school roofs were designed and constructed with a predominately flat profile. His opinion was that to re-roof a flat roof, without adding pitch and a metal roof, was a travesty and their school board was determined not to allow that to continue. He asked us to contact Blake Giddens at Restoration Engineering, Inc. (REI), since their firm provided most of the roof engineering services to their district. That contact yielded no positive information about an upcoming school project, but, instead, an interest in converting a flat roof on a condominium in Ocean City, MD to a sloped, painted, aluminum roof. Blake indicated that he was somewhat aware of the concept of adding slope to a flat roof, but was asking for whatever advise and suggestions we might have in order for him to provide a design that was “right the first time”. Of course he could have prepared a loosely put together specification and generic plan and hoped that a contractor would be capable of filling in the design holes, but he, instead, was very receptive to engineering and detailing that was proven effective over time.

REI provided a full set of detailed plans and specifications that accurately depicted his expectation for the metal retrofit roof. Included in his specifications was the requirement that the contractor prepare a set of engineered shop drawings showing how his basic design concept would be satisfied by the contractor’s approach and materials. BSC was fortunate to be selected out of three (3) bidders to construct the metal retrofit roof.

The bid stage was “done right” and yielded a competent contractor, skilled and experienced in metal retrofit roofing. After a proper contract was executed, the contractor began the design process. Over the years everyone has seen good and bad attempts at providing shop drawings. The “bad” ones use standard details pasted together to yield a patch-work of drawings and details, none of which truly depict the actual conditions of the particular roof. The “good” ones actually measure the existing roof, perform wind design load calculations, perform fastener pull tests from the existing structural components, and provide a set of scaled drawings and details that truly describe how the metal retrofit roof is to be applied to the existing flat roof. The second approach is more time consuming and costly, but was the only way to “do it right the first time”. On this particular project, BSC knew that this was the only way to proceed.

First the new roof needed to be properly designed. ASCE-7-05 was used to determine the wind speeds and corresponding wind uplift loads in all specific areas of the new metal roof. That is the critical foundation for any roof project, but, unfortunately, is one that is often given little importance. A mistake here could have devastating effects in the future. Need I say….”Do it right the first time”?

During the design process, materials needed to be selected. The coastal environment called for an aluminum roof and galvanized steel sub-framing members. An Englert S2500 aluminum panel (.040”), with a Kynar based paint system was selected to be placed on an MBCI, 16 gage, galvanized, sub-framing system. The ASTM E-1592 uplift tests for the Englert panel was obtained to determine where clip supports were necessary, then appropriate framing was designed to adequately transmit the wind design loads into the existing building structure. Normally a light gage banding system would have been utilized to stabilize the new sloped roof structure, but 16 gage angles were used instead to further add stiffness to the framing system which might have to withstand 120 mph coastal winds. In addition, the owner wished to add a 7’-0” roof overhang over the decks of the top units, in order to provide shade. While the structural members were designed to cantilever over this space, exterior columns were added by agreement of the owner, REI, and BSC. This addition, was a little “belts & suspenders”, but assured all involved that we would not ever have to worry about the coastal winds disturbing this condition. We didn’t want to come back later, but, rather, “do it right the first time”.

Now, some14 months after that board member stop at the booth in Virginia, we had located a willing owner with a need, a very capable engineer to create a bid and contract package, a contractor willing to do the work for a set price, and a finished design and needed materials selected. All that had to be done now is to put it all together! The project was started on January 14, 2008 and completed June 20, 2008. An experienced subcontractor was retained to lead the construction activity, with BSC employees working with them to accomplish the needed work. Critical to this process was BSC’s Project Manager, Phil Lisak. Although this was his first metal retrofit roof project of this complexity, Phil provided the necessary controls on material procurement and scheduling, as well as monitoring the progress of the work. This vital part of the construction puzzle is often overlooked. It is sometimes assumed, incorrectly, that a well designed project, with a qualified crew, will always produce a good final product. Unfortunately, metal roof construction is not that simple. Phil proved to be up to the many challenges associated with this job, including one of the most important….motivating the men to perform quality work. That required him to know what the shop drawings were depicting, as well as having the tenacity to make sure things were put where they were supposed to be. At the same time, the men needed to be motivated to perform the work in an efficient and effective manner. The driving force for him was to get the roof components installed as they were designed and “do it right the first time”. With only a few minor exceptions, that was accomplished. The majority of roof lawsuits in the metal roofing industry are caused by faulty installations. The main reason that a project does not make the margins expected is attributed to faulty installations and a lot of re-work dollars spent. Phil did an excellent job of working with the men to insure that there was no faulty workmanship. And the final results…..zero punch-list in late July after a walk-through with Blake Giddens…Great job, Phil.

So, in summary, there are eight (8) major components that make up a well planned and executed metal retrofit roof project:

1. A building owner that understands the long term benefits of converting a flat roof that leaks into a sloped one that doesn’t.
2. A competent design professional providing a detailed set of bid and contract drawings.
3. An experienced metal roof contractor, with experience in metal retrofit roofing.
4. A set of engineered shop drawings based on ASCE 7-05 wind uplift calculations and ASTM E-1592 metal panel wind uplift testing provided by the contractor. These need to be prepared by a licensed professional engineer with experience in this area.
5. Materials which are appropriate for the specific design.
6. Installers who are well qualified in this type of work and who understand the concept portrayed in the shop drawings.
7. A project manager that is capable of motivating the work force to produce a quality product in a specified amount of time.
8. Most importantly, doing all of the above “right the first time”.

There you have it. From John Martindale wanting to make sure his company “did it right the first time” by attending METALCON in 2003, to his company insisting that the Orleans Court Condominium project was designed and installed “right the first time”. The metal retrofit roof market provides a great opportunity for companies like BSC that believe in this, but also provides great risks for those that do not. Make sure you are one of the contractors that are successful and “do it right the first time”.

Metal Retrofit Roofs for Schools: AN EDUCATED CHOICE

“Isn’t there someway that we can pitch our old school roofs to eliminate the leaking problems? We have been told that it is too expensive to slope our flat roofs, but we know that we have a continuous expense to maintain our flat roofs. Can you help us?” Over the past 20 years I have heard this plea from frustrated school officials. The answers are simple. Yes, you can convert your flat roofs to sloped roofs. No, it not too expensive. And, yes, there is help to accomplish this much wanted remedy.

The Problem: Flat Roofs
Every school system in the United States has had problem flat roofs. By far the majority of the school structures built for the “baby boomer” generation in the 50’s and 60’s utilize a flat roof construction. This type of construction holds water on the surface of the roof, requiring the top membrane to be completely impervious to the infiltration of water through its surface. Whenever this membrane wears out, splits, or is punctured the infiltration process starts. As anyone with a flat roof will testify, once this infiltration process starts, the integrity of the roof membrane, especially with a flat roof, rapidly decreases. It can therefore be adequately defined that the problem with flat school roofs are that they are: 1) flat and 2) constructed from a membrane that is vulnerable to the elements. A study performed by the Ohio Department of Education indicated that over 20 percent of the local school’s budgets associated with buildings and grounds were spent on roof repair, maintenance, and replacement. This category accounted for the highest percentage of all categories surveyed. Similar studies have shown that this situation exists throughout the school systems of the United States. It cannot be appreciably improved while the majority of our school roofs remain flat.

The Solution: Metal Retrofit Roofs
With the problem being that school roofs are flat, it is obvious that the solution to this problem is to pitch the old flat roofs. To make this process even more successful, the use of metal standing seam roofs on these sloped surfaces allows them to last many times longer than other common roofing materials.
Life cycle costing indicates that the least expensive roof system that can be used is a sloped metal standing seam system. A study done by American Iron and Steel Institute (AISI) indicated that a sloped standing seam metal roof system was the lowest cost roofing system out of eight surveyed, over a twenty year period.
In the school market, almost all of the structures are expected to last considerably more than twenty years. The conclusion is that the sloped standing seam metal roof is the least expensive alternative for schools today.
There are many different systems available today to turn flat roofs into pitched metal roofs. The good news, therefore, is that there is a solution available to the frustrated school official who has been paying for leaking flat roofs.

Metal Retrofit Roofs–Three (3) Steps to Success
Converting flat roofs to sloped metal roofs involves three (3) basic steps. They are as follows:

1. Analyze the existing roof – Analyze the condition of the existing roof. If minor flashing and/or membrane repair will not yield long term results, a slope conversion process is in order. If the existing structure appears to be adequately supporting the existing flat and ponded roof, it should be adequate to support the new sloped metal roof system and associated framing. While this preliminary assumption will need to be verified by a licensed professional engineer, the original structure is normally capable of the increased dead loads (approximately 2.25 psf).

2. Add slope to the flat roof – The slope conversion process is accomplished by installing a light gage steel sub-framing system. This system is designed to collect the required design loads and transfer them to the existing structure. Again, this analysis needs to be performed by a licensed professional engineer in order to insure that the new composite structure can resist the design loads. The composite structure consists of the existing roof structure plus the new retrofit framing system. It is critical that the two (2) systems perform as one system after the conversion process is complete.

3. Install a metal standing seam roof system –
After slope has been created for the roof component of the building envelope, install a structural standing seam roof system, utilizing a concealed fastener system to attach the roof panels to the sub-framing. The roof panels should be at least 24 gage steel panels utilizing a GALVALUME® substrate. This coating system has been in the roofing market since 1972 and actual field tests show it lasting well beyond its warranted life of 20 years. In addition, factory coil-coated paints can be applied over the Galvalume® substrate to add color to the new roof. These coating systems, also, have been performing in field conditions well beyond their normal warranted life of 20 years.

In conjunction with the three (3) step metal retrofit roofing process, several other elements of the existing flat roof can be positively altered. First, unfaced blanket insulation can be installed on top of the existing roof membrane prior to the installation of the new metal roof membrane. This insulation can dramatically alter the energy consumption of the building by providing a much warmer “hat” for that building. Next, the cavity created between the old roof and the new roof will be ventilated. This ventilation process will allow the existing roof membrane to dry without, in most cases, the costly and risky process of removing this roof while the building is being occupied. In addition, ventilation of the cavity will not allow heat build-up in the summer and condensation in the winter. Working together, this better insulated and ventilated cavity will greatly reduce heat gain and/or loss through the roof. This benefit, alone, many times allows the metal retrofit roof system to pay for itself within 10 to 15 years.

The Source for Help

Now that you have determined that the cost and problems associated with maintaining a flat roof are outweighed by the benefits of converting it to a sloped metal roof, where do you get help? If there are not readily identifiable metal roof retrofit contractors in your area, contact a reputable metal roof manufacturing firm for names of contractors that have experience in this type of roof system. Make sure that the manufacturer supports a contractor base that is required to be trained by the manufacturer prior to weathertightness warranties being issued. Once a local contractor(s) is located, ask him to meet with you and see your roof. He will, at little or no cost to you, let you know how a metal retrofit roof can be installed over your existing flat roof, and the costs associated with such a project. This will allow you to make budgeting decisions and arrange for necessary funding. Since most school capital projects require public bidding, a design professional will need to be hired to produce plans, specifications, and bid documents. Ask the contractor for a list of local architects and/or engineers that are familiar with metal retrofit roofing. This process of involving the contractor prior to hiring a design professional will allow you to make basic financial decisions before committing to design costs.

Metal Retrofit Roofs; The Educated Choice
The use of metal retrofit roofs allows school districts to end their prolonged costs and aggravations associated with flat roofs. It allows the flat-roofed buildings to undergo a transformation into a sloped-roof building. These new roofs can be either low sloped “functional” roofs or high pitched “architectural” roofs, depending on the expectations of the owner. Both, however, eliminate the ponding condition that has continued to accelerate the roof membrane deterioration and leaking potential of the existing roof throughout the years. This new roof configuration will allow the owner to enjoy a roof system that will last well beyond its 20 year warranties. In addition, added insulation will allow the entire new roof to pay for itself within that same warranty period, making the roof system not only preferable, but, also, yielding a net life cost of zero. Your existing flat roofs can be converted to sloped roofs. You now have the tools to make such a process happen. It is your building. Make an educated choice.

For more information about the many aspects of the metal retrofit roofing market for schools, contact Chuck Howard with Metal Roof Consultants (MRC) at (919) 465-1762. You can also get information about MRC www.metalroofconsultants.net.

Winchester High School – A Retrofit Success Story

Winchester, Indiana is located in eastern Indiana, close to the Ohio border. It is a farming and light manufacturing area where the same families have lived for generations. It is a proud community, where people go to church together, help each other in times of need, and go to high school sports and band competitions with passion and pride that transcends gender and politics. It is the kind of community where everybody knows everyone else, and fundamental values and differences are few. A flat and leaking roof at the high school made an impact that split this quiet community and caused actions and words that have seldom been witnessed before.

During 2007 it became obvious that another patch on the classroom wing of the high school was again failing. The students and teachers were coexisting in an interior environment that was wet, humid, and had a very distinctive and repulsive smell. The school board, working hard to solve this problem, solicited advice from a conventional roof trade association that works primarily with flat roofs, and an architectural firm that also specialized in flat roof work. In January 2008, the board elected to proceed with the architectural firm to design and have constructed another flat roof on the high school. That decision did not sit well with many in the community. Further research by the school board uncovered the possibility of constructing a slight slope over the existing flat roof and adding a metal standing seam roof system. This possibility was introduced at the February board meeting, which started a heated debate, pitting proponents of flat roof retrofit against sloped metal retrofit. It was quoted in the local paper, The News Gazette that “each side accused the other of only hearing what they want to hear…” By the time the March meeting came around, there had been a protest by the students refusing to occupy the classroom wing due to the leaks and smell, and, as reported by The News Gazette, “approximately 200 parents and students” attended the board meeting because “they were angry over the roof.” By the end of the meeting the architect hired to provide the flat roof design had left the meeting and indicated that he did not wish to proceed with such a contract.

On March 31, 2008 Metal Roof Consultants (MRC) was asked to attend a special board meeting to present a sloped metal retrofit roof alternative for the school’s roof woes. A visit to the site generated information and pictures for a PowerPoint presentation. This presentation, concerning a metal retrofit roof possibility, was presented to approximately 100 parents, teachers, students, and, of course, board members. The concept of not removing the old roof, but allowing it to dry out naturally in the dry and vented cavity created by the metal retrofit process made common sense to those in attendance. There had not been time to “dazzle” those in attendance with technical facts about the structural characteristics of this system, the many colors they had to choose from, or the massive energy benefits inherent with this type of roof system. However, they did hear about a concept that would allow them to permanently solve their continuing roof problems with a tried and true system that would probably be the last roof for this building. All in attendance, including the board members, applauded after the presentation as a sign of relief that they could finally all agree upon a positive direction for a permanent solution to Winchester high school’s roof. MRC was awarded a contract to prepare the design, drawings, and specifications for such a roof and procure bids for its construction. The community was united and at peace again.

Dr. Greg Hinshaw assumed his responsibilities as the new superintendent of the school system on July 1, 2008. He inherited a commitment to proceed with putting a sloped metal retrofit roof on the high school, but no money for construction. Through his diligent efforts, loan money was procured from the state of Indiana, and the project was bid in September 2008. The low bidder was Smarrelli Construction of Richmond, Indiana and MBCI was approved as the supplier of the metal materials required for the 108,000 SF project. MBCI provided the final design and material package; using their NuRoof system and BattenLok HS roof panels. The contract price was approximately $1.6 million, which was slightly less than the original architect’s estimate for the removal and replacement of the existing flat roof system with another flat roof system. Work began in December 2008 and will finished in October 2009.

The retrofit metal roofing system consisted of leaving the existing roof in place, which allowed school to continue while the new roofing system was installed. It also eliminated the need to remove the existing roof, with the need to dump these used materials in the local landfill. It has been estimated that approximately 15% of all landfill materials consists of non-recyclable roofing materials. With the metal alternative, these materials remain in place, thereby being kind to our environment. In addition to leaving these materials, 6” of un-faced fiberglass insulation was installed directly over the existing roof. This material not only raised the insulating value of the roof by approximately 640% (R-3.5 to R-22.5), thus saving energy costs, it allowed the existing roof to “breathe” and release its moisture content through the glass insulation into the ventilated air in the new roof cavity and expelled from the cavity through vents at the high sides of the roofs. The new roof panel, even though painted a bronze color, utilized Energy Star paint additives that created a “cool roof” reflecting approximately 80% of the solar heat back into the atmosphere and not into the building. All of these benefits of the metal roof make this roof an extremely “green” roof, reducing the carbon footprint of the building and saving precious energy dollars.

In addition to the energy benefits of the metal retrofit roof, the materials should last the remaining lifetime of the school building. The painted roof system, while guaranteed for twenty (20) years, should provide 50 to 60 years of service with no maintenance other that checking the roof periodically to insure that no external damage (tree limbs, ice damage, etc.) has occurred. And of course, since metal is not negatively affected by ultraviolet rays, the metal surface will not break down from the suns affect. And, of course, the new metal retrofit roof does not leak! It is guaranteed for a minimum of twenty (20) years to not leak. Since the materials will last much longer, the guarantee period is merely the beginning of the time the school system should expect the roof to provide protection.

What do the superintendent, Dr. Hinshaw, and the principal, Tom Osborn, have to say about their metal retrofit roof experience?
Tom Osborn, Principal of Winchester High School:

“In the spring of 2008 the flat roof of our 42 year old building suffered substantial problems. Leaks became overwhelming. The roof on the section of the building that houses the academic programs failed to the extent that several halls were lined with trash cans to catch the constant drips caused by spring rains and the thawing of ice and snow. As the roof and ceiling became saturated, the humidity level grew inside the building. Students were relocated to other rooms as another cold patch was applied to stop the water penetration. There was serious doubt, however, about whether any amount of repair work could save the roof and whether the old roof would ever dry out even if it could be made waterproof again.

Metal Roof Consultants (MRC) was hired to lead the school corporation through the process of installing a standing seam metal roof later that spring. Construction progress was steady throughout the 2008-2009 school year. MRC; the general contractor, Smarrelli’s of Richmond, IN; and the staff of Randolph Central worked together in a cooperative collegial manner. MRC provided us with a design that is attractive as well as weather tight. The ventilation system helped quickly dry out the old roof even to the point that extra insulation has been added to the attic cavity to help the HVAC system. Our 42 year old building now has a professional new appearance that has helped return pride in our facility to the community, staff and students. There is new feeling of optimism and Randolph Central again has a building that we believe can safely and efficiently serve the youth of our schools for many years to come. I can sincerely say that the final product has far exceeded the expectations of anyone who was here at WCHS in March of 2008! We are very pleased with our decision to undertake this project and install a standing seam roof.”

Gregory P. Hinshaw, Superintendent of Schools, Randolph Central School Corp.:

“The need for roof replacement at Winchester Community High School was, by far, the most pressing issue when I became superintendent in the summer of 2008. Fortunately, the school board had already employed Metal Roof Consultants to engineer a new roof, and construction began in the fall. The new roof has totally changed the exterior appearance of the building, and our students, faculty, and public have all been very supportive of the process. The retrofit roof has improved the appearance, environment, and energy management of the building. We are very pleased with the project.”

Metal retrofit roofing has restored the peace in Winchester, Indiana. Through diligent efforts by the all involved in the school system, they now have an attractive, energy efficient, and long lasting roof system that will continue to serve their district for many decades to come. Now they can get back to academics, church, sports, band………

Author’s Comment: It has been a pleasure, as President of MRC, to assist the Randolph Central School Corporation with the metal retrofit roof on the Winchester High School building. I applaud the board members, superintendent and principal in their diligence and cooperative approach to solving their roofing problem.

MRC can be contacted at (919) 465-1762 or at chuck@metalroofconsultants.net for further information concerning this project of metal retrofit roofs in general. Chuck Howard, PE