Buildings are complex and expensive. Owners must weigh competing priorities and make decisions that serve the building’s long-term purpose and the immediate concerns of the project budget. It often falls to the design and construction professionals on the job to communicate that the least-expensive solution to spec is seldom the best option in the long term. This is particularly true of roofing systems.
“It’s natural for parties to focus on first costs in the absence of a more important goal, which is why I advocate for a preliminary design step that clearly identifies the owner’s goals,” explains Ron Harriman, president of Benchmark Inc., a roofing consulting firm in Cedar Rapids, Iowa. Harriman has worked in the industry for almost four decades. “When the discussions start with the lowest-cost options, things can go off track. Owners are then put in an exceedingly difficult position of not understanding the risks of low-cost solutions and, therefore, have a hard time justifying something other than the lowest first cost.”
It’s important for design professionals, roofing contractors and consultants to fill in the knowledge gaps for the owner in terms that are meaningful for them. Helping owners see the very tangible operational and economic benefits of durable, resilient design is important to the owners’ holistic understanding of the building. There are places in which investing more money upfront can tremendously benefit the bottom line.
One such area is applying a cover board to a roofing system, a thin substrate to which a roof membrane adheres. A relatively small additional investment on the front end, a cover board is one way an owner can improve the longevity of a roof and significantly reduce the risk of major damage from severe storms, fires and other threats. Although not a requirement in a roof assembly, when considering the potential expense of a major roof repair or replacement and potential closures or damage to the building, cover boards can be a worthy addition.
Building Beyond Code
But why make the extra investment in roof durability? Roofs are a true workhorse on any building; they perform at a high level for many years while standing up to numerous environmental and human-caused stresses during their intended life.
In construction, it’s common to think primarily of first costs when making material choices and to look to building codes to inform standards of durability and performance. However, it is worth noting codes traditionally represent only the minimum requirement for operation.
As weather conditions around the U.S. continue to generate more severe events and climate-related risks put additional stress on buildings, it’s increasingly clear that the minimum found in the codes may no longer suffice. There has been a notable rise in wildfires in the Western United States, and the damage and costs associated with severe storms and hail continue to grow in other parts of the country. (See “Very Severe Hail”, page 2.) Even recently, sudden heavy rain and snow events in California and other western states have put additional loads on the roofs of buildings that likely were not designed for that kind of stress.
According to data from the UN’s IPCC Climate Report, the entire world currently is experiencing extreme weather events which we can expect to continue to increase in the coming years. When making investments in buildings that are expected to last for decades, it is prudent to design for durability that will allow those buildings to endure stressful conditions and continue to operate.
Durable Design
To make the case for the best, most efficient roof system to an owner, a designer, contractor or roofing consultant will need to frame the discussion in terms of operation, maintenance and return on investment. The repair or replacement of a damaged roof can be expensive, both in actual terms and in revenue lost during building closure. A dollar spent upfront guarding against a major repair can save several dollars later.
No matter what kinds of external threats a roof may face in its environment, giving careful attention to durability and resiliency throughout the process, from design and material selection through operation and planned maintenance, can pay enormous dividends in the long-term life of the roof.
“I often reflect on a Roofing Industry Committee on Weather Issues [RICOWI] study of hurricane-damaged roofs,” Harriman says. “RICOWI categorized all the failures with the following causes: design, materials, workmanship and maintenance. For roof systems to perform long term, thought must be given to these factors.” Learn more about RICOWI and its research.
A roof cover board can increase the resiliency of a roofing system. A 2020 FMI roof cover board survey of owners found that using a cover board on a single-ply membrane roof increased the median life expectancy by four years and reduced operation and maintenance costs by an average of $1.40 per square foot over a 20-year lifespan. An increased percentage of roof assemblies that met their full life expectancy was also seen in roofing systems that included a cover board. Without a cover board, 52 percent met their full life expectancy; with a cover board that number rose to 86 percent. (FMI Roof Cover Board Survey completed in May 2020. Actual results may vary.)