By Anne Vazquez
Published in the June 2010 issue of Today’s Facility Manager
As long as people have needed shelter, they have put some form of roofing into service on the structures they build. Thousands of years ago, thatched roof materials (dried vegetation such as heather and straw) were introduced to protect people and their belongings from the elements. When properly designed, this type of cover is quite waterproof, provides insulation qualities, and can last for 40 to 50 years. If a facility manager (fm) was considering a thatched roof today, however, he or she would quickly dismiss it as an option upon learning of it very poor fire spread rating.
Over the ensuing centuries, roofing design and materials have evolved, and in 2010, fms have a vast array of choices available to them. A staple of the roofing industry throughout the 20th century, multi-layered tar or asphalt and gravel represent perhaps the oldest modern flat roof systems. These are highly resistant to foot traffic and are recognized for long-term performance. However, in the quest for even better performance and maintainability, as well as environmentally friendly benefits, these roof materials have increasingly given way to the use of polymers, foams, fabrics, and metals—in a variety of combinations—for building modern roofs.
Issues To Consider
Whether looking to install a completely new roof or rehabilitate an existing surface, most fms will rate high the following factors as project priorities: durability, appearance, and energy efficiency. In evaluating whether to repair or replace an existing roof, fms will want to inspect the current conditions; it is prudent to call on a qualified consultant or contractor when making a major decision about the future of a roof. Such a service provider will be able to recommend effective materials and methods, install those materials in a code compliant and sturdy fashion, and provide as much guidance as desired on proactive maintenance practices for the life of the roof.
Rob Hillman, marketing manager, 3M Industrial Products Division, St. Paul, MN, says, “In addition to general benefits, durability, cost, sustainability, etc., decision makers should also carefully consider organizational stability throughout the value chain, training provided by the manufacturer and contractors, and service to repair and maintain post installation.”
Fms dealing with the decision of whether to repair or replace their roofs need to take into account the budget, code compliance, and long-term goals (e.g., increasing energy efficiency), among other issues. Each type of roof structure (e.g., flat, low slope, pitched) presents its own specific needs. However, the desire for durability, energy efficiency, and cost-effectiveness are common to all.
“With respect to new installations,” says Fred Sitter, marketing director, Duro-Last Roofing, Inc., Saginaw, MI, “we are seeing requests for more robust roofing system assemblies—additional insulation, thicker membranes, stronger underlayment, sturdier edge details, stronger wind uplift attachment, etc. All of these factors help improve a roofing system’s durability and long-term performance and reduce the need for intensive maintenance and preservation methods.”
Dennis M. Delby of Architectural Roof Design Group, Inc., special projects consultant for RoofMart International, Chapman, KS, says, “In deciding on a new roof, the first consideration should be code compliance. Second is the impact on occupancy during reroofing. Third is the impact of occupancy or operations on the selected roof membrane (e.g., contaminants, traffic), and fourth is cost. Most would say cost first, but if you do not [address] the first three, the cost will be overwhelming during the life of the roof.”
He continues, “Any trend toward restoration has taken new meaning in the event of the ‘Great Recession.’ Restoration is now beginning more with preventive maintenance, which allows an fm the ability to work within tightening budgets. Depending on the condition of an existing roof, a restoration may fall into cost range close to or rivaling a new roof. The poorer the condition of the existing roof, the greater the cost of restoration.”
Evaluating The Roof Elements
Whether new or rehabbed, a roof system should be specified with materials that are compatible and will work together to protect and last.
For evaluating and planning any roof project, Chris Tobias, national accounts manager, Firestone Building Products, Indianapolis, IN, provides other advice: “Are all of the equipment and penetrations on the roof functioning, or can they be consolidated or removed? What type of contaminants will the surface be exposed to? Is aesthetics a concern? Acrylic roof coatings can be applied over many membranes to increase thermo-reflectivity and add aesthetic value. And, do you need another level of protection from high speed winds and hail? Manufacturers typically have systems specifically designed to provide these levels of protection. The same applies to fire resistance.”
Assuming the structure of the facility supporting the roof is in good shape and does not require remediation, fms can work from there up when planning for a new or rehabbed roof. Generally speaking, this involves insulation, roof deck, underlayment, and surface (asphalt, plastics, gravel, or metal). Surface choices also include vegetative materials for those who wish to install various types of green roofs.
Specifying an insulation system that facilitates proper roof performance is fundamental, but performance is only one factor to keep in mind. Fms should also consider the thermal needs of the facility and applicable energy codes.
Choice of an insulation product generally needs to be made in close connection with the membrane type and application method. As such, fms should consider selecting an insulation product that includes: membrane compatibility; energy code (R-value requirements); insurance and code requirements regarding wind and fire; and strength (compressive strength for traffic and hail resistance).
Says Reinhard Schneider, DensDeck technical manager, Georgia-Pacific Gypsum, LLC, Atlanta, GA, “Looking at trends going forward, adding durability is an essential focus to preserving existing roofs. [One way] this can be achieved is by adding a rigid, strong coverboard with a new membrane or coating to restore and make the roof assembly more durable and protect the insulation below.”
In considering loads on the roof, Schneider notes, “A new factor in overloading is the reality that more insulation is being used below roofs than ever before, causing snow to stay on the roof longer. This can contribute to deterioration and potential for collapse. So, when new roofs are put in or retrofitted, it is crucial they are analyzed for this additional, longer lasting snow load scenario.” [For more about snow loads, see sidebar at the end of this article.]
Roofing Toward Sustainability
As most fms know, the role of the roof in a building’s energy efficiency level is also a growing concern. Says Schneider, “With energy costs rising, considering energy efficiency and insulation value is critical. Along with this is the sustainability and durability of the roofing system. A system made efficiently—and to withstand foot traffic and other maintenance factors—is always the goal.”
Proper insulation, reflective surfaces to reduce heat absorption, and environmentally friendly materials are all factors to consider. Sitter says, “The trend to white, reflective, energy saving roofing is undeniable and has become a key decision making factor. This focus on white roofing is part of a larger fm interest in sustainability that extends to the manufacturer of the roofing system. This includes film production, reinforcement scrim, fabrication scrap, flashing parts and accessories, shipping materials and methods, installation components, fasteners, and so on.”
Says Tobias, “The desire to be green has also led to dramatic increases in the thermal code for insulating buildings. As a result, new roofing technologies that provide thermo-reflectivity—such as white EPDM, TPO, and bright white modified systems and reflective roof coatings—are in higher demand, as is thorough life cycle cost analysis.”
Another trend includes an increase in the number of rooftop vegetative systems and photovoltaic systems. While still a relatively small part of the market, these applications are attracting attention. Hillman notes, “Existing roofs are being increasingly retrofitted to be sustainable and productive. Needs are advancing beyond cost, shelter, and protection and driving towards overall usability. From providing rainwater harvesting to integrated solar systems, the perception of the roof as an asset is evolving.”
Also commenting on this trend, Schneider says, “Fms need to know that these additions add stresses to a roofing system, such as additional load, installation, and ongoing maintenance traffic.” [To read about this emerging role of roofs, read “Protective Planning,” TFM, February 2010.]
Tax Breaks For Greener Roofs
In researching roof improvements, fms should look into what tax benefit they may be able to glean from the federal Energy Policy Act of 2005 (EPAct) Commercial Building Tax Deduction (CBTD). This deduction was designed to encourage energy efficiency investments in building envelope, interior lighting, and HVAC/hot water systems. (Government facilities, and other entities that do not pay taxes cannot take the deduction but may pass the savings on to a qualified service provider.)
The tax deduction was scheduled to expire on December 31, 2008 but has been extended to December 31, 2013. The CBTD provides for a deduction of up to $1.80 per square foot in structures built or renovated using strategies certified to reduce annual energy costs by at least 50% (compared to a reference building that meets minimum requirements of ASHRAE Standard 90.1-2001).
When pursuing a roofing improvement only, fms can take the partial deduction of up to 60¢ per square foot. For this scenario, certification would be required stating that the individual system (e.g., roof) is expected to reduce energy costs by 16 2⁄3%, compared to a Standard 90.1-2001 reference building.
Shares Hillman, “Improving building reflectivity has allowed our customer base to apply for [the] credits.”
Insulation comes into play here as an area of opportunity as well. “[When reroofing, it] offers one of the best paybacks on a building owner’s investment,” says Tobias. “Insulation works day and night, in warm and cold climates.”
Bird’s Eye View
After evaluating the condition of a roof, fms can then gather information on available materials and assembly methods. Manufacturers, consultants and contractors, and industry associations are useful sources. Identifying roof weaknesses and strengths, and how those align with long-term facility planning—both literally and figuratively—will help to determine the best course of action.
What roofing projects are you evaluating right now? Send questions to email@example.com.