April 21, 1999
BCAB #1479
Re: Combustible Landscape Structures on Roof of Noncombustible Buildings, Sentence 3.1.5.1.(1) ('92 BCBC)
Project Description
The project in question is a five storey residential building designed in conformance with Article 3.2.2.37. The roof will be landscaped and divided into 19 individual spaces for the use of the building's tenants. These spaces are intended to be divided by four foot high cedar fences and the spaces will contain several two foot high wood planters. There is also a 150 foot long by four foot wide wood trellis proposed to cover the common walkway that provides access to the exits.
Reason for Appeal
Article 3.2.2.37. requires the building to be of noncombustible construction. Noncombustible construction is "defined" in Subsection 3.1.5. Articles 3.1.5.2. to 3.1.5.19. list various combustible components permitted to be used in noncombustible construction. The landscape elements described in the project description are not described in any of the Articles.
Appellant's Position
The appellant contends that the wooden fences, planters and trellis are landscape elements and are not governed by Subsection 3.1.5. which does not reference any non-building elements such as signage, awnings, fencing or other landscape elements.
Building Official's Position
The building official maintains the proposed combustible structures are not permitted. Permitted combustible components related to roofing are plywood nailer facings on parapets and cant strips. These items present no additional hazard to an occupancy on the roof. Presumably, if the code sees a need to exempt such components, it is by extension not permitting other combustible items not specifically mentioned in Subsection 3.1.5. In addition, the BC Fire Code prohibits the storage of combustible materials on a roof in such a manner as to create a fire hazard to the building or its occupants. The Fire code would not permit storage of the materials to build the landscape elements so it seems logical that the same materials should not be permitted to be used to construct structures on the roof.
Appeal Board Decision #1479
The Board notes that combustible landscape elements on a roof are not specifically addressed in Subsection 3.1.5. However, many other combustible components of equal or greater combustible load are permitted in noncombustible construction. The board considers the external landscape elements to present less of a potential hazard than other permitted combustibles within the building and suggests an equivalency should be considered.
George R. Humphrey, Chair