Complete Stair Building GuideNBC Code, Calculations & Materials
Everything about building stairs in Canada — from measuring rise and run to meeting NBC code. Covers anatomy, calculations, stair types, materials, and costs.
Quick Answer
For NBC-compliant stairs: max 200 mm (7-7/8") rise, min 235 mm (9-1/4") run, min 860 mm (34") width, min 1,950 mm (6'5") headroom. Divide total rise by 190 mm for steps. Use 2×12 SPF for stringers.
Stair Anatomy
Key components and terminology for stair construction.
- Rise (Riser Height): Vertical distance between treads. NBC max 200 mm (7-7/8"). All within 6 mm.
- Run (Tread Depth): Horizontal distance nosing to nosing. NBC min 235 mm (9-1/4").
- Stringer: Diagonal structural member. 2×12 SPF lumber for notched stringers.
- Tread: Horizontal stepping surface. 5/4×12 or 40 mm hardwood. 20–30 mm nosing.
- Riser: Vertical board. 1×8 (20 mm).
- Nosing: Front edge overhang. 20–30 mm.
- Handrail: Required on one side for 3+ risers. Height 865–1,070 mm (34–42").
- Baluster: Vertical members. Max 100 mm (4") gap.
Understanding these components is essential for NBC compliance.
NBC Building Code (Section 9.8.2)
The National Building Code of Canada Section 9.8.2 sets minimum standards. Provincial codes may be stricter.
- Rise: Max 200 mm (7-7/8"). All within 6 mm.
- Run: Min 235 mm (9-1/4").
- Width: Min 860 mm (34").
- Headroom: Min 1,950 mm (6'5").
- Handrail: Required on one side for 3+ risers. 865–1,070 mm high.
- Landings: Top and bottom. Min 860 mm deep.
- Guards: Required when drop > 600 mm. Min 900 mm high (1,070 mm for common stairs).
- Lighting: At top, bottom, and landings. 3-way switches for 6+ risers.
NBC minimums — check your provincial code. Always obtain a building permit.
How to Calculate Stairs
Calculate step count, rise, run, and stringer length.
- Step 1 — Measure total rise between finished floors.
- Step 2 — Divide by 190 mm (7-1/2") = risers. E.g., 2,700 / 190 ≈ 14.
- Step 3 — Actual rise = 2,700 / 14 = 192.9 mm. Check ≤ 200 mm.
- Step 4 — Run: min 235 mm. Rise + run = 430–460 mm.
- Step 5 — Treads = risers - 1 = 13.
- Step 6 — Total run = 13 × 250 = 3,250 mm.
- Step 7 — Stringer = √(2,700² + 3,250²) = 4,223 mm.
- Step 8 — Check 1,950 mm headroom everywhere.
Use our free Stair Calculator for instant NBC-compliant results.
Common Stair Types
Type depends on space, budget, code, and aesthetics.
- Straight: Simplest. One flight. 3–4.5 m run. Most economical.
- L-Shaped: 90° turn at landing. Common in Canadian two-storey homes.
- U-Shaped: 180° turn. Less length, more width.
- Spiral: Compact. From 1,100 mm (44"). Secondary access in lofts or basements.
Straight when space allows. L or U for limited space. Spiral for secondary access.
Materials & Costs
Material affects cost, durability, appearance, and maintenance.
| Material | Cost per Step | Best For |
|---|---|---|
| Pressure-Treated SPF | CAD $10 – $20 | Exterior stairs, decks, budget |
| SPF (Kiln-Dried) | CAD $12 – $25 | Interior framing, carpeted stairs |
| Red Oak Hardwood | CAD $30 – $60 | Interior finished stairs, stained |
| Composite | CAD $40 – $80 | Exterior, low-maintenance decks |
| Concrete (Precast) | CAD $50 – $120 | Exterior entries, basements |
Cost Breakdown
Costs vary by design, materials, and DIY vs contractor.
Exterior basic: CAD $400–$1,200. Interior straight: CAD $2,000–$6,000. Oak treads: +30–50%. Pro installation: +CAD $1,500–$4,000.
L/U: +20–40%. Spiral: CAD $2,000–$7,000 (kit) to $30,000+ (custom).
DIY saves 40–60%. Straight staircase in 1–2 weekends.
Calculate Your Project
Use our free stair calculators for instant NBC-compliant dimensions.