BCAB #1693 - Occupancy Classification of Detached Garage, Article 9.10.11.2.

April 21, 2011

BCAB #1693

Re: Occupancy Classification of Detached Garage, Article 9.10.11.2.

Project Description
The project in question is a four unit fee-simple row house with two detached two car garages. There is a party wall in each garage such that half the garage is on one property and the other half is on the adjacent property.

Reason for Appeal
Article 9.10.11.2. permits a party wall between side by side dwelling units in a residential building to be constructed as a fire separation with a 1 hr fire resistance rating instead of a noncombustible firewall with a 2 hr fire resistance rating.

Appellant's Position
The appellant contends that the party walls in the detached garages should be afforded the same allowance as the party walls between the residential suites. Table 9.10 2.1. notes that garages serving individual dwelling units are not considered as Group F Division 3 major occupancies which implies they should be considered as Group C residential occupancies.

Building Official's Position
The building official maintains that the allowance for a party wall to be a one hour fire separation only applies between dwelling units and as the garages are not dwelling units the party walls must be noncombustible 2 hr firewalls.

Appeal Board Decision #1693
It is the determination of the Board that the detached garages are subsidiary to the residential Occupancies and are considered part of the associated dwelling units for the purposes of Article 9.10.11.2.

George Humphrey, Chair