BCAB #1950 - Protection of Foamed Plastic Insulation and Protection from Mechanical Damage

January 2, 2025

Re: Protection of Foamed Plastic Insulation and Protection from Mechanical Damage

Project Description

The project is the design and construction of a new Part 9 house of wood frame construction.

In an area located above the main living space, the house includes a space identified on the building permit plans as “attic space/future rec room”.  The space is 107.4m² in area, of which 66.1m² has a ceiling height of 2.1m or greater.  The space can only be accessed by a ladder; the plans include provisions to add stairs in the future.  The space is conditioned, within the heated building envelope.  A plywood floor is provided and the floor structure is designed to support live loads.  A gypsum board ceiling is provided on the underside of the roof trusses located above the space.

The exterior walls of the attic space/future rec room contain foamed plastic insulation and an air/vapour barrier.  It is proposed that the gypsum board on the walls only be installed in the future, after wiring is installed and when the stairs are constructed under a new building permit.

Applicable Code requirements (BCBC 2024)

Sentence 9.10.17.10.(1), Division B, Protection of Foamed Plastics (excerpt)

(1) Except as provided in Sentences (2) and (3), foamed plastics that form part of a wall or ceiling assembly shall be protected from adjacent space in the building, other than adjacent concealed spaces within attic or roof spaces, crawl spaces, wall assemblies and ceiling assemblies

(a) by one of the interior finishes described in Subsections 9.29.4. to 9.29.9., . . . 

Sentence 9.25.2.3.(7), Division B, Installation of Thermal Insulation

(7) Insulation located in areas where it may be subject to mechanical damage shall be protected by a covering such as gypsum board, plywood, particleboard, OSB, waferboard or hardboard.

Decision being appealed (Local Authority’s position)

The truss space above the attic space/future rec room is bounded by the roof above and the ceiling below and meets the definition of attic or roof space; the attic space/future rec room does not meet the definition of attic or roof space.  Further, due to the overall configuration of the space and its location within the house, the attic space/future rec room is capable of holding occupant loads at any time.  For those reasons, the foamed plastic insulation requires protection.

Despite being currently unfinished, the attic space/future rec room can easily be occupied and used.  Therefore, the insulation is susceptible to mechanical damage and must be protected by a covering.

Appellant's position

The attic space/future rec room is currently an attic space and the foamed plastic insulation does not currently require protection.  The attic space/future rec room is accessible only by ladder and the walls are not susceptible to mechanical damage so a wall covering is not currently required.

Appeal Board Decision #1950

The Board varies the decision of the local authority.

It is the determination of the Board that the attic space/future rec room is a floor area and a second storey within the building.  The foamed plastic insulation requires protection and the insulation requires protection from mechanical damage.

Reason for decision

The area in question does not meet the definition of attic or roof space and does meet the definitions of storey and floor area.

The foamed plastic insulation requires protection because the exemption granted to concealed spaces within attic or roof spaces does not apply.

The insulation requires protection from mechanical damage because walls in a floor area are susceptible to mechanical damage.

The Board notes that there are various requirements that apply to storeys including egress by a stair with guards, and smoke alarm(s).

Don Pedde
Chair, Building Code Appeal Board