Development Permit Bylaw and Minister’s Orders Effective Immediately

As reported in CodeNews 340, the Ministry of Municipal Affairs and Housing (MMAH) made amendments to Ontario’s Building Code (O.Reg. 89/23) that came into force May 12, 2023.

Combustible Components in Wall Assemblies & Cladding: New Options

For Group ‘C’ and ‘D’ buildings of combustible construction (up to six storeys with sprinklers), revisions to the cladding requirements have been implemented.

Not less than 90 per cent of the exterior cladding on each exterior wall should be non-combustible cladding or a wall assembly meeting CAN/ULC-S134, “Fire Test of Exterior Wall Assemblies.” The test has been updated over the decades, so check for the currently referenced version. The same two options, for these same building types, is also possible when the building faces only one street (see OBC 3.1.4.8.(2) and clause 3.2.2.10.(3)(b)).

CAN/ULC-S134 tests measure fire spread over the cladding, from a post-flashover fire in a compartment, venting through a wall opening (i.e. fire spread over the exterior surface, or storey, above the opening). The change to OBC 3.1.4.8.(1) permits combustible components for exterior non-loadbearing wall assemblies and introduces further harmonization with the National Building Code of Canada (NBC).

Previously, the only permitted type of cladding for theses building types was non-combustible for 100 per cent of each building face. With the 10 per cent allowance for combustible cladding in Clause 3.1.4.8.(1), fire‑retardant-treated wood (tested per ASTM D2898, Accelerated Weathering of Fire-Retardant-Treated Wood for Fire Testing) can be incorporated into the design.

Clauses 3.1.4.8.(1)(b), (2)(b), and (3) broaden the possibilities for the use of combustible materials, which may include low-embodied-carbon renewable resources, such as lumber framing or furring, and test-compliant wood cladding.

Additionally, Sentence 3.2.3.7.(3) has been replaced to allow the exterior wall cladding of encapsulated mass timber construction, with a permitted area of unprotected openings over 10 per cent of the exposing building face, to be noncombustible when the wall assembly complies with the criteria for combustible components of exterior walls of OBC 3.1.5.5.(1).

Stacked Townhomes and Mid-rise Business and Personal Services Occupancy: Various Changes to Four- and Six-storeys

Changes influencing the design of mid-rise construction include:

• For Group ‘C’ and ‘D’ buildings of combustible construction, up to six storeys with sprinklers, combustible piping, and tubing is no longer permitted (Article 3.1.4.9 has been removed entirely).
• For Group ‘C’ and ‘D’ buildings of combustible construction, up to six storeys with sprinklers, exit separations are no longer required to be non-combustible (see revised Clause 3.2.2.43A.(2)(e)).
• Four-storey Group ‘C’ buildings of non-combustible construction, or of combustible construction with sprinklers, are now included in the permitted exceptions for standpipe systems (refer to the new Clause 3.2.9.1.(8) for limitations to the exception).
• For Group ‘C’ and ‘D’ buildings of combustible construction, up to six storeys with sprinklers, the requirement for Class ‘A’ fire-rated roof coverings are revoked for roof heights below 25 m (measured from the first-storey floor to the highest point of the roof). This allows for the possibility of a six-storey building (even with the added height of a sloped roof) to be exempt from the previous requirement for a Class ‘A’ fire rated roof covering. This exemption has also been extended to encapsulated mass timber construction.

Changes to the Planning Act: Development Permit Bylaw and Minister’s Orders

The More Homes for Everyone Act, 2022 made changes to the Planning Act to create a Minister’s order authority known as the “community infrastructure and housing accelerator” tool. The Minister of Municipal Affairs and Housing is authorized to make orders to respond to municipal requests for expedited zoning outside of the Greenbelt Area.

OBC Clause 1.4.1.3.(1)(j) has been revised to include the authority of Minister’s orders, under section 34.1 of the Planning Act, in the defined term applicable law. When an order is made upon request of the municipality, the order may be exercised in a development permit bylaw. Applicants for building permits are required to establish compliance with applicable law. Now, Minister’s orders can establish compliance with applicable law for the purpose of a building permit application.

Update: Demountable Stages and Support Structures (Footings)

As reported in the March 2023 Practice Advisory, new provisions were added in the OBC about demountable stages and support structures.

Some additional context on footings for demountable stages and demountable support structures has been added; members involved in such structures may want to review information in OBC Section 4.2 for allowable bearing pressures (based on subsurface investigations) or according to the newly added option of maximum allowable bearing pressures noted in Table 9.4.4.1 (see revised Sentence 3.16A.2.8.(4)).