When can an exterior guard be lower than 1 070 mm?
An exterior guard may be 900 mm high when the walking surface it serves is not more than 1 800 mm above the adjacent finished ground.
Conditions and exceptions
- Measured from the walking surface to the top of the guard.
- Applies to guards serving not more than one dwelling unit.
- Above 1 800 mm the guard returns to the 1 070 mm minimum.
- Interior guards and stairs are governed separately.
Where this comes from
National Building Code of Canada — Part 9
This page states the requirement and points you to the publisher. It does not reproduce the code text — read the provision itself at the official source below.
Read the official text at NRC — Codes Canada publications →Verify this against the code edition actually adopted where you are building. Provinces, territories, and municipalities amend on their own schedules, and where the governing document and this page disagree, the governing document controls. This is not legal, engineering, or permitting advice. Last reviewed 2026-08-12.
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