BCAB #1682 - Combustible Components in Noncombustible Construction, Articles 3.1.5.5. and 3.1.5.12.

December 16, 2010

BCAB #1682

Re: Combustible Components in Noncombustible Construction, Articles 3.1.5.5. and 3.1.5.12.

Project Description
The project is a sprinklered office building containing business and personal service occupancies as well as medium hazard industrial occupancies.  The building is required to be noncombustible.

Reason for Appeal
Article 3.1.5.5. provides for the limited use of combustible components in a non-loadbearing exterior wall assembly in a building required to be of noncombustible construction.  Article 3.1.5.12. provides conditions for the use of combustible insulation in a building required to be of noncombustible construction.

Appellant’s Position
The appellant contends that combustible insulation is permitted by 3.1.5.12. and therefore the  requirements of 3.1.5.5. are not applicable.  The requirements of 3.1.5.5. are intended to apply only to combustible elements not specifically listed in 3.1.5.  The scope of 3.1.5.5. is limited to combustible cladding as indicated by title of the supporting appendix note.

Building Official's Position
The building official maintains that the requirements of 3.1.5.5. and 3.1.5.12. are separate and that the requirements of both articles must be met in the use of combustible insulation in an exterior wall assembly.

Appeal Board Decision #1682
It is the determination of the Board that both Articles 3.1.5.5. and 3.1.5.12. apply to combustible insulation in non-loadbearing exterior wall assemblies and the insulation must conform to the provisions of both Articles.

George Humphrey, Chair