A Case Study on Spray Foam’s Many Uses in Commercial Buildings
Provided By Huntsman
When applied to the exterior of commercial buildings, in either new or retrofit situations, SPF can greatly reduce energy use, air infiltration and water intrusion. The two primary areas where SPF is used on the exterior of buildings are walls and roofing applications.
SPF IN EXTERIOR WALLS
One of the positive attributes of SPF is that it is a very versatile building material. SPF is compatible with many wall types and can be sprayed onto the exterior sheathing in new construction projects, or assimilated between stud cavities in retrofit situations.
SPF-insulated buildings have superior thermal performance due to the air barrier properties SPF provides, as well as reduced thermal bridging through the studs. In addition, studies have found that SPF can improve the structural integrity of the building in areas of high wind events by increasing the “racking strength” of the walls.
One of the most important attributes of closed cell SPF in external wall applications is that it is an effective water barrier, as well as an air control layer. Moisture intrusion is one of the biggest threats to the structural integrity and durability of commercial buildings, accounting for up to 89 percent of damage to the building envelope (Source: Bomberg, M.T. and Brown, W.C. (1993), “Building Envelope and Environmental Control: Part 1-Heat, Air and Moisture Interactions” Construction Canada 35 (1), 15-18). Reducing moisture intrusion through the wall, whether in vapor or liquid water form, is critically important for the long-term durability of the structure and health of the occupants.
Another benefit of using SPF in exterior walls is that it can mitigate some of the natural air pressure forces that can impact energy efficiency. Testing of wall assemblies by Architectural Testing Inc. demonstrated SPF with its air infiltration reduction characteristics performed better than fiberglass insulated wall assemblies at low and high temperatures with induced air infiltration (Source: ATI ASTM C 1363-05 THERMAL PERFORMANCE TEST REPORT).
Because SPF allows very little air permeation, there is almost no measurable movement of air through the insulation material as is common in fiberglass or cellulose insulation. This helps reduce the negative effects of air movement within the building envelope, such as “wind washing” and the stack effect.
SPF IN ROOFS
Roof failure is a primary cause for water intrusion into the building, and traditional methods of removing and replacing roofing material can be expensive and expose the structure to additional damage. SPF can be used as a re-roofing material, applied directly on the existing roof structure. It provides two important benefits to a building through waterproofing and increased insulation value. Further, the application of SPF to an existing roof structure is simple and fast. The expanding foam is simply applied directly over the existing metal, wood, concrete, membrane or built-up roofing material. Once the SPF has been applied to the proper thickness, a protective layer of elastomeric coating or gravel is applied over the insulation. This combination of foam insulation and protective layer produces a durable, weather-resistant surface that is strong enough to walk on.
In new construction, SPF is ideal for flat commercial roofs because it is lightweight, durable, and requires less maintenance compared to traditional roofing systems. Once applied, SPF can help make roofs weatherproof and has a 30 year expected service life. Additionally, as a roofing material, SPF also increases the structural strength of the building by providing wind uplift resistance, which can be critical in hurricane-prone regions.
When installed on the interior of walls or as part of the floor system, SPF is an integral part of the overall design strategy to improve comfort, indoor air quality and durability, and to reduce energy bills. Both walls and floors can be places of air infiltration, especially in industrial settings, and have the potential of water intrusion, especially in the form of vapor. SPF in these areas can help promote a healthier and more durable space for the occupants.
SPF IN INTERIOR WALLS
Interior walls in commercial buildings can benefit from SPF in a number of ways, including noise reduction and isolating specific areas of the building from adjacent workspaces.
Conference rooms, executive offices and human resource departments are all areas in commercial office buildings where sound mitigation is critical in order to maintain a professional atmosphere. Open cell spray foam has strong sound reduction properties, often employed in recording studios to mitigate sound intrusion. Reducing sound transmission within a commercial building is also important in manufacturing facilities, like bookbinderies, that operate noise-generating machinery. Other buildings that could benefit from noise reduction between interior walls include hospitals, hotels, and schools.
Another successful application for SPF in interior walls of commercial buildings is in industrial settings, where air quality issues can impact adjacent workspaces.
Manufacturing facilities that generate airborne toxins or pollutants need to be isolated from the administrative areas of the building. This can include automotive repair, paint and body shops, chemical companies and printing facilities where paper dust is generated.
SPF IN FLOORS
Similar to the challenges of interior walls, floors can benefit from reduced noise transmission and air infiltration when SPF is applied. This is especially true in office buildings and hotels, where sound transmission through the floor can be especially disruptive. •