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Slabs for accessory buildings

It's officially spring - we can tell at the planning office, because of the dramatic increase in permit applications for garages.

Effective Jan. 1, all accessory structures larger than 55m2 (592 square feet) must be built to the standards of the National Building Code of Canada - and that means that any accessory building of 55m2 (592 square feet) footprint or larger must have either

  1. frost wall bearing on a foundation at 4' depth (or solid rock)
  2. piers (sonotubes) bearing to a foundation at 4' depth (or solid rock)
  3. screw piles (engineered)
  4. an engineer-designed slab-on-grade foundation.

It's vital for applicant to realize that submitting a permit for an accessory building with a slab-on-grade foundation MUST include a drawing of the slab stamped by an engineer qualified to work in the province. If this isn't part of your application, it will delay the issuance of a permit.

More on slabs here.