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Trade engines · Architectural
Rooms, stairs and egress, measured from the drawing.
The deepest trade in the engine, and the one most sets are opened for. Twenty-eight of the fifty-four Ontario rules filed under architectural are answered by measuring the drawing; the rest are printed with their clause for a person to confirm.
1.0 What is measured
What the engine reads off the drawing
Every reader runs on every file, whichever trades the audit is scoped to. Choosing this trade decides which rules get reported. The drawing is read either way.
Rooms, from traced outlines
Each room’s area and its ceiling height, measured from the walls as drawn rather than from the label. A 7.0 m² minimum for a sleeping room is checked against what was drawn.
Stairs, riser by riser
Rise, going, clear width and the total rise between landings: the four numbers that decide whether a flight passes, each read from the section or the plan it is drawn on.
Openings, from the schedule
Door and window sizes come from the schedule where the set states one, and the egress window check compares the opening against the bedroom it serves.
2.0 The rules
54 Ontario rules, and which of them read the drawing
Answered from the drawing means the check reaches a pass or a fail from what was extracted. Checklist means the rule is printed with its clause for a person to confirm. Both are useful on a permit set, and only the first is a finding.
| Clause | What it requires | How it is answered |
|---|---|---|
| OBC 2025 Article 3.8.3.3(1) / AODA Built Environment Standard | Accessible door clear width minimum 860mm | From the drawing |
| OBC 2025 Article 3.8.3.4(1) | Accessible ramp maximum slope 1:12 (8.33%) | From the drawing |
| OBC 2025 Article 3.8.3.4(2) | Accessible ramp minimum clear width 1100mm | From the drawing |
| By-law 569-2013 Article 10.5.20.40 | Maximum building height 10.0m in standard RD zones | From the drawing |
| OBC 2025 Article 9.5.1 | Building height data — verify against zoning maximum | From the drawing |
| OBC 2025 Article 9.5.3.1 | Exit door clear width must be at least 860mm | From the drawing |
| OBC 2025 Article 9.5.3.1 | Exit door height must be at least 1980mm | From the drawing |
| OBC 2025 Article 9.8.4.1(1)(a) | Stair riser height must not exceed 200mm | From the drawing |
| OBC 2025 Article 9.8.4.1(1)(a) | Stair riser height must not be less than 125mm | From the drawing |
| OBC 2025 Article 9.8.4.1(1)(b) | Stair tread going (depth) must not be less than 235mm | From the drawing |
| OBC 2025 Article 9.8.4.1(2) | Stair clear width must not be less than 860mm | From the drawing |
| OBC 2025 Article 9.8.4.3 | Maximum vertical rise between landings must not exceed 3700mm | From the drawing |
| OBC 2025 Article 9.8.7.1 | Handrail required on stairs with 3 or more risers | From the drawing |
| OBC 2025 Article 9.7.4.3 | Sleeping rooms must have an egress window with opening area ≥ 0.35 m², min dimension 380mm, sill ≤ 1000mm AFF | From the drawing |
| OBC 2025 SB-12 Table 12.2.1.5 (CZ6) | Above-grade wall effective thermal resistance (CZ6): RSI 4.03 minimum | From the drawing |
| OBC 2025 SB-12 Table 12.2.1.5 (CZ6) | Attic/ceiling minimum RSI-10.14 (R-57.6) for Climate Zone 6 | From the drawing |
| OBC 2025 SB-12 Table 12.2.1.5 (CZ6) | Foundation wall minimum RSI-3.85 (R-21.8) for Climate Zone 6 | From the drawing |
| OBC 2025 SB-12 Table 12.2.1.5 (CZ6) | Slab-on-grade perimeter insulation minimum RSI-1.76 (R-10) for Climate Zone 6 | From the drawing |
| OBC 2025 Article 9.3.4.2 | Attached garage must be separated from dwelling with 12.7mm Type X gypsum board | From the drawing |
| Ontario Fire Code 2025 Article 3.3.2.1 / OBC 9.3.4 | Fire separation between attached garage and dwelling: minimum 30 minutes | From the drawing |
| OBC 2025 Article 9.7.2 / 9.7.4.3 | Each bedroom must have at least one window for natural light and egress | From the drawing |
| OBC 2025 Article 9.7.2.1 | Habitable rooms must have window area of at least 10% of floor area | From the drawing |
| OBC 2025 Article 9.7.2.1 | Bedroom window area must meet minimum 10% of floor area requirement | From the drawing |
| OBC 2025 Article 9.5.4.1 | At least one habitable room in each dwelling unit must have a floor area of not less than 13.5 m² | From the drawing |
| OBC 2025 Article 9.5.4.2 | Sleeping rooms (bedrooms) must have a floor area of at least 7.0 m² | From the drawing |
| OBC 2025 Article 9.5.5.1(1) | Habitable rooms must have ceiling height of at least 2100mm over 75% of the required floor area | From the drawing |
| OBC 2025 Article 9.5.5.1(1) | Habitable rooms (living) must have ceiling height of at least 2100mm | From the drawing |
| OBC 2025 Article 9.5.5.2 | Bathrooms must have a ceiling height of at least 1950mm | From the drawing |
| AODA 2005 / OBC 2025 Part 3.8 | Full AODA compliance review — scope depends on building type and occupancy | Checklist |
| AODA Built Environment Standard — Visitability | Visitability standard — level access to main entrance and accessible powder room on ground floor | Checklist |
| OBC 2025 Article 3.8.2.1 | Vertical access — elevator or platform lift required where all storeys must be accessible | Checklist |
| OBC 2025 Article 3.8.2.2 / AODA | Accessible parking space minimum 3400mm wide with adjacent 1500mm access aisle | Checklist |
| OBC 2025 Article 3.8.2.3 | Accessible route clear width minimum 1100mm | Checklist |
| OBC 2025 Article 3.8.2.4 | Minimum 1500mm diameter clear turning circle for wheelchair maneuverability | Checklist |
| OBC 2025 Article 3.8.3.3(4) / AODA | Accessible door hardware must be lever-type or automatic — no round knobs | Checklist |
| OBC 2025 Article 3.8.3.3(6) | Accessible door threshold maximum 13mm height | Checklist |
| OBC 2025 Article 3.8.3.4(4) | Accessible ramps with rise > 75mm require handrails on both sides | Checklist |
| OBC 2025 Article 3.8.3.6 / AODA | Stair nosings must have contrasting colour and non-slip surface | Checklist |
| OBC 2025 Article 3.8.3.8 | Accessible washroom — review triggered by building use and occupancy | Checklist |
| OBC 2025 Article 3.8.4.1 | Accessible signage — tactile and Braille room identification required in multi-unit common areas | Checklist |
| OBC 2025 Article 9.25.4.1 | Vapour barrier required on warm side of insulation in all exterior walls and ceilings | Checklist |
| OBC 2025 Article 9.27 / OFC General | Combustible cladding — OBC Part 9 buildings have no height restriction on combustible cladding | Checklist |
| By-law 569-2013 Article 10.5.20.45 | 45-degree angular plane restriction from rear lot line — manual review required | Checklist |
| OBC 2025 Article 9.1.1.1 | Storey count — confirm building qualifies as Part 9 | Checklist |
| OBC 2025 Article 9.5.1 | Storey count must be verified for Part 9 applicability | Checklist |
| Ontario Fire Code 2025 Article 2.2 | Ontario Fire Code compliance — annual fire safety inspection required for multi-unit buildings | Checklist |
| TGS Version 4 — General | TGS Tier 1 Compliance Checklist must be submitted with permit application | Checklist |
| Ontario Fire Code 2025 Article 2.8.2 | Exit signs required for multi-unit or secondary suite buildings | Checklist |
| Ontario Fire Code 2025 Article 3.3.4 | Travel distance to exit must not exceed 25m within a residential suite | Checklist |
| Ontario Fire Code 2025 Article 3.3.5 | Secondary means of escape from below-grade sleeping areas | Checklist |
| Ontario Fire Code 2025 Article 3.3.2.2 | Fire separation between dwelling units (suites): minimum 30 minutes | Checklist |
| OBC 2025 Article 9.8.8.1 | Guards required at open sides of floors, decks, balconies at height ≥ 600mm, minimum 900mm high | Checklist |
| OBC 2025 Article 9.8.8.3 | Guard openings must not allow a 100mm sphere to pass through | Checklist |
| By-law 569-2013 Article 10.5.10.20 | Secondary suite (basement apartment) — zoning permissions and OBC requirements | Checklist |
Counts and clauses are exported from the rule packs themselves, by the same function the trade picker inside Blueprint Auditor calls.
3.0 Outside Ontario
What the other packs carry
Ontario is the deepest pack because it is where the rules were written first. Each column shows what that pack holds today, and a zero is a zero rather than a blank.
| Pack | Rules in this trade | Answered from the drawing |
|---|---|---|
| Ontario | 54 | 28 |
| British Columbia | 16 | 16 |
| National Building Code (Canada) | 16 | 16 |
| California | 21 | 20 |
| Florida | 25 | 20 |
| New York City | 25 | 20 |
| IRC (model code) | 21 | 20 |
| England | 7 | 7 |
4.0 What it does not do
Said before you pay for it
- A set with no door or window schedule gives no opening sizes, and the audit says so rather than assuming standard sizes.
- Room areas are measured to the clear face of the wall. A drawing that states nominal areas will disagree with the measurement by the wall thickness, which is the convention and not an error.
- Accessible design is checked against the dimensions on the drawing. Whether a route is usable is a judgement no measurement makes.
- Nothing here is a permit approval. It is the first pass an experienced reviewer makes, done in minutes and cited to the clause.
Bring the hardest set you have.
A real set off a live job. The audit runs in minutes and every finding carries the clause and the sheet, so you can check the ones you disagree with.