BCAB #1952 - Required Exterior Guards

February 6, 2025

Re:  Required Exterior Guards

Project Description

The project is the construction of a new single-family residence on a sloping site.

The upper level consists of interior floor areas as well as an exterior flat roof area.  The exterior flat roof includes areas that intended to be occupiable space on an exterior terrace, including a hot tub and shower area as well as a pathway that provides the only access to an interior office space.  The exterior flat roof also includes areas that are not intended to be occupiable and have “self-sustaining ground cover”.

The roof areas intended for occupancy are separated from other roof areas by a barrier rail consisting of a single top rail at 900 mm above the walking surface supported on intermittent posts.  The barrier rail at the occupiable boundary is at least 1.5 m inboard of the edge of the roof in all locations.

Where the edge of the hot tub is located along the occupiable boundary, the barrier rail is located 900 mm above the edge of the hot tub.  In some locations, 600 mm wide planter boxes which extend approximately 450 mm above the walking surface are placed immediately adjacent and outboard of the barrier rail and are intended to be herb gardens, tended and harvested from the walking surface side only.

Applicable Code requirements (BCBC 2018)

Sentences 9.8.8.1.(1) and (2), Division B, Required Guards

(1) Except as provided in Sentence (2), every surface to which access is provided, including but not limited to flights of steps and ramps, exterior landings, porches, balconies, mezzanines, galleries and raised walkways, shall be protected by a guard on each side that is not protected by a wall for the length where

(a) there is a difference in elevation of more than 600 mm between the walking surface and the adjacent surface, or

(b) the adjacent surface within 1.2 m of the walking surface has a slope of more than 1 in 2.

(2) Guards are not required

(a) at loading docks,

(b) at floor pits in repair garages, or

(c) where access is provided for maintenance purposes only.

Decision being appealed (Local Authority’s position)

The roof area intended to be used as occupied space for access to the hot tub and the office requires guards.  The barrier rail complies with neither the height nor the opening size limitations for guards in the Code.  The barrier will not prevent children or pets from walking under the barricade and onto the ground cover, thereby being exposed to a risk of falling from the roof edge.

The hot tub, shower, and the rooftop office accessed from the exterior terrace are not maintenance purposes so the Code exemption in Clase 9.8.8.1.(2)(c), Division B, does not apply.

Appellant's position

The occupiable roof terrace is the surface to which access is provided.  This area has unit pavers as a walking surface and is bounded by a perimeter visual and physical barrier which prohibits access to areas that would only be accessed for maintenance purposes.  The limiting of access is nowhere defined in the Code as equivalent to a guard.

There is no difference in elevation of more than 600 mm between the walking surface of the terrace and the adjacent surfaces within 1.2 m of the delineated walking surface.

Guards are not required at the perimeter of the occupiable roof terrace.

Appeal Board Decision #1952

The Board reverses the decision of the local authority.

It is the determination of the Board that the intended walking surfaces on the occupiable portion of the roof are more than 1.2 m from an area where there is a difference in elevation of more than 600 mm.  Guards are not required at the perimeter of the walking surface.

Reason for decision

The portions of the roof that are not intended to be occupied are approximately level with, or higher than, the walking surfaces.  The elevation drops between the walking surfaces and the adjacent surfaces are, therefore, less than 600 mm.  The adjacent surfaces within 1.2 m of the walking surfaces have slopes of less than 1 in 2.

The Board considers that the perimeter barrier delineates the edges of the walking surfaces.  The distances between the edges of the walking surfaces and the outside edges of the roof are not less than 1.2 meters, therefore the construction complies with Sentence 9.8.8.1.(1), Division B.

Don Pedde
Chair, Building Code Appeal Board