There are four methods in which a plastic (and spray polyurethane foam [SPF]) can comply with the code. Figure 2 illustrates three of the four methods: the prescriptive (grandfathered) method in black and two exceptions (deviations) in blue. These exceptions are permitted for specific approaches to meet the code without direct compliance to 2603.4.
The fourth method, the equivalent compliance method, identifies a multi-test protocol (National Fire Protection Association [NFPA] 275) for achieving an equivalent rating to gypsum (Figure 3). Any product that strives to be equivalent to 12.7 mm (0.5 in.) gypsum must meet this protocol of tests.
Governing organizations
When one gains an understanding of these four compliance/approval avenues defined in IBC, another layer of complexity forms. There are many governing groups, including global and national organizations, the federal government, and even states that mandate initiatives. Figure 4 (page 36) is an example of the organizations that govern insulation in buildings. Some allow direct interpretation of the IBC and others require stiffer requirements than the IBC or IRC. In many cases, the IBC and IRC are the “minimum required approvals” to be used in the building industry.
‘Alphabet soup’: Construction compliance-related acronyms
In Figure 5, the alphabet soup of requirements is sometimes conflicting, as section Unified Facilities Guide Specifications (UFGS) 07 27 36 describes. This confuses even the most experienced construction participants. Thus, the information presented here focuses on IBC and IRC code needs only.
Understanding code requirements
Understanding code requirements can be quite overwhelming and even confusing for inspectors and fire marshals, as more complex layers of code are added to the sections around plastics. Keep in mind, the sprayfoam industry is relatively new in the world of construction. Equipment to sprayfoam insulation was only invented in the late 60s (Gusmer created the sprayer in 1962) and its growth and acceptance by construction codes did not exist until the 1970s.2
As expected with so many governing organizations, many of which overlap and cover different domains in the construction industry, SPF serves many masters. Compliance gets quite complicated, trying to supply all the documentation required, especially for the two exception-based compliance methods.
Direct compliance with gypsum, where feasible, is a much easier and cost-effective execution. Historically, equivalent thermal barriers were “add-ons” to the SPF and inherently added cost, labor, and inspection/documentation steps. As codes have changed, the challenges for compliance with these approval methods are continually tested. Specific examples of how each of these entities drive different compliance requirement challenges include:
