Designers and specifiers building or upgrading a multifamily home must consider the energy efficiency of the building and select the right insulation during the design phase of the project. Energy-efficient buildings not only help building occupants save on their monthly energy usage, but they help reduce potential impacts to the environment. And it’s not just something many building occupants want, it’s increasingly becoming a requirement for builders and specifiers. To meet these new requirements, it’s critical for builders and specifiers to understand the construction materials available so they can make the best possible decision.
Whether it is new construction, a renovation or a retrofit job, spray polyurethane foam insulation (SPF) is well positioned to meeting energy-efficiency requirements and client demands for building comfort. SPF offers a multi-attribute solution to insulating, air-sealing and improving the strength of buildings with one product, saving time during construction, increasing comfort, making building maintenance easier and increasing the resilience and durability of the structure. When used in a retrofit job, SPF can also address some of the problems often found in chronically under-maintained buildings and make them more efficient and sustainable.
Because it offers one of the highest R-values on the market, SPF helps makes homes more energy efficient and helps avoid the generation greenhouse gas emissions contributing to climate change. In addition, when properly installed and fully cured the U.S. Environmental Protection Agency has found SPF is inert and nontoxic. 1
Thermal Performance
SPF can offer the highest R-value per inch, which means greater potential energy savings. Typical R-values for SPF range from 3.5-7.0 per one inch of thickness. The higher R-value allows certain SPF products to provide the same energy savings in half the amount of space that may typically be required.
Air Sealing
SPF is applied on-site as a liquid. When the SPF cures, it expands in place to insulate and seal the spaces seen and unseen. SPF’s unique application process allows it to create a layer of protection that provides a consistent air seal for walls, roofs, ceilings or floors, which helps minimize air leaks and saves energy. Other insulation products usually need additional products (building wrap or tape) to air seal the building envelope – adding to the savings potential of SPF.
Sealing gaps with spray foam can also minimize air-borne sound transmission. Open-cell foam can reduce high frequency noise, and closed-cell foam can reduce low-frequency noise. A combination of open- and closed-cell foams can help maximize noise reduction – certainly a valuable attribute in a multifamily building.
Building Strength and Resilience
The Federal Emergency Management Agency (FEMA), which responds to natural disasters, has classified SPF insulation as highly resistant to floodwater damage, saying, “These materials can survive wetting and drying and may be successfully cleaned after a flood to render them free of most harmful pollutants.” 2
Applying closed-cell spray foam in the cavities of the walls increases durability of the wall system3 because of the foam’s ability to conform and adhere to the surface upon which it is sprayed. When the National Institute of Standards and Technology (NIST) examined buildings following Hurricane Katrina in Pascagoula, Miss., it found that buildings with SPF roofs performed remarkably well. The SPF kept the roofs intact and prevented moisture from entering the buildings, and it also protected the roofs from hail and debris. Only one of the buildings with an SPF roof had notable damage and, in that case, it was minor, affecting a mere one percent of the roof. 4
Closed-cell SPF insulation can be applied below the roof deck to help secure the roof by essentially gluing the roof deck to the structure. A roof deck insulated with ccSPF has demonstrated an ability to withstand wind speeds found in category 4 hurricanes (130-156 mph). Moreover, ccSPF below the roof deck performs as a secondary water barrier in the event shingles and underlayment are torn off by high winds.
The Clear Choice
For many reasons, SPF continually proves itself to be the clear choice for builders and specifiers who need to meet energy-efficiency requirements because its multifunctional nature allows it to upgrade the building in many ways and it makes housing stock more durable, comfortable and appealing. For more information about SPF, please visit whysprayfoam.org.
1 Environmental Protection Agency. Methylene Diphenyl Diisocyanate (MDI) and Related Compounds Action Plan [RIN 2070-ZA15]. April 2011.
2 “Flood Damage-Resistant Materials Requirements” FEMA Technical Bulletin 2, August 2008.
4 https://ws680.nist.gov/publication/get_pdf.cfm?pub_id=908281 page 70
