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………

 

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”.

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

Metal Roofing Over Metal Roofing

When the large warehouse and industrial metal building roofs of the 1950’s and 1960’s started to fail, including one of his own, one of the true pioneers in the metal building industry, “Red” McConnohie, recognized a problem needing attention. “Red” set out to develop a system that allowed a new metal roof to be installed without the cost and liability of removing the existing roof. He knew others had used hat sections attached to the major ribs, but that approach depended on the new roof loads being transferred into the existing structure through only the old skin of the existing metal roof. Engineering reviews of that method proved it to be inadequate for wind load transfer.

A structurally sound, long term solution for metal roofs was needed. Whoever knows “Red” also knows that he is not one to give up when there is no obvious answer to a question and soon enough he determined that a “Notched Zee” was going to be the best solution. This modified purlin would span over the ribs and rest firmly on the flat portion of the existing roof panel allowing the fasteners to go directly through the base flange of the zee and old panel, and into the existing structure. Thus was born the Roof Hugger system which has been in use since 1991.

As we all know, what can be devised in plan does not always work in the “real world”. This method of reroofing an existing metal roof with a new metal roof, without having to remove the existing roof, however, is one of those plans that work. The obvious benefits are as follows:

1. No need to remove the existing roof panels, exposing the interior to the outside elements.
2. No interior space contamination from air borne particles such as dust, dirt, rust, etc. caused by the roof removal.
3. No need to remove existing roof insulation. Additional insulation can be added between the old and new roof, improving existing energy performance.
4. Edge and corner conditions, per ASCE 7, require higher wind uplift resistance than was originally designed. The Roof Hugger system can be designed to meet these new code requirements. This design work must be performed by a licensed professional engineer in the state where the system is to be installed. The professional will identify the loads per the applicable code, review the panel system capacities and check the framing system to insure each element will adequately perform its’ structural task.
5. Roof Huggers can significantly increase the existing sub-structural support system, as well as structural rigidity.
6. Many of the old metal roofs that need replacing were attached by “through fastening” directly into the metal panel surface. Over many years of expansion and contraction, these fasteners were either loosened or created an elongated hole in the surface of the metal panel. Conditions that allowed water to infiltrate the weathering surface. Part of the retrofit process is to choose a new metal roof panel system. Today’s standing seam roof systems are attached by concealed clips and provide uplift resistance while being able to slide up and/or down slope as the panel expands and contracts, eliminating this panel trauma.
7. Many first generation paint systems on the original metal roof allowed the finished surface to chalk, fade, or peel excessively. Today’s roofs can be permanently replaced by a new roof panels with Kynar or equal based paint systems field proven to last 35 years and more.

Examples of how the Roof Hugger system has been used throughout the USA are as varied as their locations. Three (3) such case studies, showing the benefits of how this system can yield a new modern metal roof system, are as follows:

Printing press facility – Mobile, Alabama
a. It was determined that the panel clip spacing for a metal roof installed about 2000 was deficient. After serious consideration of options how to correct this problem, including the possibility of removing the existing roof and replacing it with another metal roof, it was determined to use a Roof Hugger system and install a new metal roof system. The owner’s architect was concerned about the cavity between the roofs being conducive to condensation formation, which was solved by filling this cavity completely with un-faced fiberglass insulation. In addition, because the clip spacings were so random, many of the edge and corner conditions had insufficient attachment points and/or incorrect attachment spacings. With the use of the roof Hugger system, these conditions were corrected by locating the new sub-structural members where needed to yield the proper spacings. All work was done without adversely affecting the continual printing processes inside the building.
b. The contractor for this project was Keith Moseley Construction, Saraland, Alabama.

Fish hatchery building – Coastal Maryland
a. This project entailed an old metal building roof constructed in the mid 1970’s. The existing roof system was attached to the building purlins by “through fastening” the panels at the purlin locations. These fasteners, over the years, had loosened in some places and caused elongated holes at the eaves.
b. The high humidity inside the building had, over the many years, permeated the interior vinyl vapor barrier enough to allow back-side condensation on the original panels. Several of the panels were deteriorating from the inside-out. Attempting to remove this insulation and metal panels would have resulted in a large amount of particulates falling into the fishery tanks below. The existing roof purlins were tested to determine that no appreciable deterioration of the top leg, necessary for proper fastener pull-out resistance, had occurred. Leaving these materials intact, and installing an exterior Roof Hugger system and a new metal panel system, allowed the project to proceed without negatively affecting the building’s interior operations.
c. The contractor for this project was Brothers Services Company, Hampstead, MD.

Middle School in central North Carolina
a. While this school system initially wanted to remove the sloped metal roof systems due to faulty paint, they opted to allow the existing roof panels to remain while a Roof Hugger system was installed, along with a new “concealed fastener” metal roof system. Since the original metal roof was not insulated, allowing condensation on the interior surface, new un-faced insulation was added in the cavity. The resultant new composite envelope had an R value that exceeded 20 as opposed to less than 2 prior to the retrofit. Of course, the new metal panels came with a 20 year guaranteed Kynar based paint system.
b. The contractor for this project was LaFave’s Construction, Landis, NC.
“Red” definitely knew what he was doing when he developed his engineered Roof Hugger system. It has proven to be an extremely effective solution to reroofing the millions of SF of warehouse and industrial metal building roofs as well as allowing for a method to rectify faulty installations of current metal roofs. This method has a proven track record, with over 60 million SF of product in place, and should be considered whenever an existing metal roof requires retrofitting.

The author of this article, Chuck Howard, PE, was privileged to be involved with the case studies mentioned. He can be contacted at chuck@metalroofconsultants.net with any questions.

Old or Damaged Metal Roofing Need Replacing?

It’s hard to believe but the fledgling metal building industry I remember from the late 60’s thru the mid 80’s is now pushing 40 years old! The industry built a lot of buildings during that period, in excess of 18 billion Square feet by most accounts. Due to industrial demands at the time, the buildings grew larger and larger. We did not have the option to use a concealed, moveable clip until the mid 70’s, and expansion/contraction forces have played havoc with these large roofs. The large warehouse and industrial metal building roofs of this circa are starting to fail as you might expect. What are our options when we get to this point with a property?

If the building owner is fortunate, the building should have ongoing operations inside, critical storage materials, or tenants that we do not want to be disturbed while we make this required repair. Taking off the old roof and replacing it with a new metal roof, a typical solution, presents us with numerous costly risks we would rather not face.

A structurally sound, long term solution for metal roof replacement is required. This solution must allow for upgrades to higher wind zone requirements, newer panel systems with energy efficient reflective finishes, greater insulation, elimination of exposed fasteners, and added capacity to properly accommodate expansion and contraction. All this work needs to be performed without shutting down the ongoing operations and exposing building interiors to the elements.

In 1991, a product was developed and patented that satisfied this growing demand of re-roofing existing metal roof with new metal roofs, without removing the original roof. This product uses a “Notched Zee” product, as manufactured by Roof Hugger, Inc. (www.roofhugger.com), and provides the best solution for these conditions. This modified purlin spans over the existing panel ribs and rests firmly on the flat portion of the existing roof panel, allowing the fasteners to go directly through the base flange of the zee and old panel, and into the existing structure. It can be designed and manufactured to a definite height for job specific ventilation or insulation requirements.

As we all know, what can be devised in plan does not always work in the “real world”. This method of reroofing an existing metal roof with a new metal roof, without having to remove the existing roof, however, is one of those plans that actually does work. The obvious benefits are as follows:

1. No need to remove the existing roof panels, exposing the interior to the outside elements.
2. No interior space contamination from air borne particles such as dust, dirt, rust, etc. caused by the roof removal.
3. No need to remove existing roof insulation. Additional insulation can be added between the old and new roof, improving existing energy performance.
4. Edge and corner conditions, per ASCE 7, require higher wind uplift resistance than was originally designed. The Roof Hugger system can be designed to meet these new code requirements. This design work must be performed by a licensed professional engineer in the state where the system is to be installed. The professional will identify the loads per the applicable code, review the panel system capacities and check the framing system to insure each element will adequately perform its’ structural task.
5. The new roof section, consisting of the original building purlin or metal deck, the original roof system, the new structural Hugger attached to the structural elements of the original materials, and the new metal roof panel, is structurally stronger that the original metal components alone.

A Recent example of how this system works can be demonstrated by a project I designed and consulted on at a printing press facility in Mobile, Alabama. The following is an account of the project:

A hurricane had exposed the fact that there were some possible deficiencies in the design and/or installation of the metal roof system. Further investigation revealed that the panel clip spacing for a metal roof, installed about 2000, was extremely random and did not meet code at the time of its installation. After serious consideration of options how to correct this problem, including the possibility of removing the existing roof and replacing it with another metal roof, it was determined to use a Roof Hugger system and install a new metal roof system. The owner’s architect was concerned about the cavity between the roofs being conducive to condensation formation, which was solved by filling this cavity completely with un-faced fiberglass insulation. In addition, because the existing clip spacing’s were so random, many of the edge and corner conditions had insufficient attachment points and/or incorrect attachment spacings. With the use of this “Notched Purlin System”, these conditions were corrected by locating the new sub-structural members where needed to yield the proper spacings. All work was done without adversely affecting the continual 24 hour per day operation inside the building. The contractor for this project was Keith Moseley Construction, Saraland, Alabama.

The Roof Hugger System has proven to be an extremely effective solution to reroofing the millions of SF of older warehouse and industrial metal building roofs, as well as allowing for a method to rectify faulty installations of current metal roofs. This method has a proven track record, with over 50 million SF of product in place, and should be considered whenever an existing metal roof requires retrofitting. This is a structurally sound way to re-roof that metal roof, without having to go to the time and expense of removing it. Use this method to rejuvenate your metal building or metal roof and give your building and its occupant’s new life.