R316.5.11

Section R316.5.11 is titled 'Sill plates and headers' and covers the requirements for allowing spray applied foam plastic insulation without a thermal barrier for sill plates, headers, or perimeter joist spaces. Maximum thickness, density range per cubic foot, maximum flame spread index, maximum smoke-developed index, and the testing standards to determine the flame spread and smoke-developed indices are established. The purpose of this section is to slow the spread of fire.

The model shows spray applied foam plastic insulation installed between floor joists adjacent to the perimeter rim joist with the allowed thickness labeled. The product specifications need to be reviewed to determine if the foam insulation complies with list items 2 and 3 of this section.