BCAB 1988 - Change of use in a garage attached to a single-family dwelling

Change of use in a garage attached to a single-family dwelling

Project Description

The project is the conversion of the unheated, attached garage of an existing single-family dwelling to accommodate a home-based hairstyling business.  The former exterior garage double-door opening now contains an infill exterior wall including a person-door and three openable windows.

Applicable Code requirements (BCBC 2024)

Sentence 1.4.1.2.(1), Division A, Defined Terms

Conditioned space means any space within a building, the temperature of which is controlled to limit variation in response to the exterior ambient temperature by the provision, either directly or indirectly, of heating or cooling over substantial portions of the year.

Sentence 9.25.1.1.(2), Division B, Scope and Application

(2) All walls, ceilings and floors separating conditioned space from unconditioned space, the exterior air or the ground shall be

(a) provided with

(i) thermal insulation conforming to Subsection 9.25.2. and Section 9.36.,

(ii) an air barrier conforming to Subsection 9.25.3. and Section 9.36., and

(iii) a vapour barrier conforming to Subsection 9.25.4., and

(b) constructed in such a way that the properties and relative position of all materials conform to Subsection 9.25.5.

(See Note A-9.25.1.1.(2).)

Sentence 9.32.1.2.(1), Division B, Required Ventilation

(1) Every dwelling unit shall incorporate

(a) provisions for non-heating-season ventilation in accordance with Subsection 9.32.2., and

(b) except as required by Sentences (2) and (3), if supplied with electrical power, provisions for heating-season ventilation in accordance with Subsection 9.32.3.

Sentence 9.33.2.1.(1), Division B, Required Heating and Cooling Systems

(1) Residential buildings intended for use in the winter months on a continuing basis shall be equipped with heating facilities conforming to this Section.

Sentence 9.36.1.3.(5), Division B, Compliance and Application

(5) Buildings or portions of buildings that are not conditioned spaces, and residential buildings that are not intended for use in the winter months on a continuing basis, are exempted from the requirements of this Section. (See Note A-9.36.1.3.(5).)

Decision being appealed (Local Authority’s position)

After conversion to a home-based business use, the former garage now forms part of the dwelling unit and must be constructed accordingly.  Insulation compliant with Section 9.25., Division B, ventilation compliant with Section 9.32., Division B, and conditioning compliant with Section 9.33., Division B, are required.

Exemption from energy efficiency requirements, as may be indicated in Sentence 9.36.1.3.(5), Division B, should not reasonably apply in this case.  However, if the exemption does apply, it extends only to Section 9.36., Division B, and not to the other requirements.

Appellant's position

The home-based business does not require conditioned space to function and the space will not be used for business operations during the winter season on a continuing basis.

The space is exempt from energy efficiency requirements in Section 9.36., Division B.  As such, it should also not be subject to the requirements of Sections 9.25., 9.32., and 9.33., Division B.

Appeal Board Decision #1988

The Board confirms the decision of the local authority.

It is the determination of the Board that the requirements of Section 9.36., Division B, apply in the floor area of the hairstyling business.

The floor area of the hairstyling business forms part of a residential building.  The overall building is intended for use in the winter months on a continuing basis and must be equipped with heating facilities.  As such, the floor area of the hairstyling business is now required to be conditioned space.  Requirements in Sections 9.25., 9.32., and 9.33., Division B, also apply.

Reason for decision

The Board acknowledges that the hairstyling business will not be used for business operations during the winter season on a continuing basis.  However, after the change of use, the floor area of the hairstyling business is considered to be part of the dwelling unit’s conditioned space.  The fact that the space is not used for business purposes during the winter months does not invalidate the requirements to provide heating and other appropriate construction in that space.

Don Pedde
Chair, Building Code Appeal Board 

Dated:  November 6, 2025