Your staircase type is determined by three factors: the layout (straight, L-shaped, U-shaped, spiral, or curved), the structural system (mono-stringer, double-stringer, or wall-mounted), and the riser configuration (open or closed). Here is a clear guide to each dimension, with Ontario Building Code specifications and 2026 cost ranges.
Ontario homeowners can find registered staircase contractors through the Home Construction Regulatory Authority (HCRA) — C.O.R.S Designs is a fully compliant Ontario staircase company.
Layout Types: How the Staircase Moves Through Your Floor Plan
Straight Staircases
A straight staircase moves from lower to upper floor in a single uninterrupted run. It is the simplest structural configuration and most visually dramatic when the full run of treads is visible from one angle.
Floor footprint: ~900 x 3,600 mm. Best for: Open-concept homes. Cost (Ontario 2026): $9,000-$20,000 installed.
L-Shaped (Quarter-Turn) Staircases
Changes direction 90 degrees at a landing. Fits into a corner, using floor space more efficiently. Fully compatible with open-riser, mono-stringer, and glass railing designs.
Floor footprint: ~1,800 x 2,000 mm. Cost: $13,000-$25,000 installed (+15-25% over straight equivalent).
U-Shaped (Half-Turn) Staircases
Makes two 90-degree turns at a mid-flight landing. Very compact linear footprint relative to the floor height accommodated.
Floor footprint: ~1,800 x 1,800 mm. Cost: $15,000-$28,000 installed.
Spiral Staircases
Rotates around a central post in helical form. Most compact footprint. Important: not recommended as the primary staircase in Ontario family homes. Moving furniture between floors is essentially impossible. Use for secondary access only (loft, basement, rooftop terrace).
Floor footprint: 1,200-1,500 mm diameter. Cost: $6,000-$18,000 installed.
Curved / Helical Staircases
Sweeps through a gradual arc. Most complex and expensive to fabricate. Each tread is a unique shape, the stringer follows a continuous curve.
Cost: From $28,000 installed. Best for prestige entryways in homes where the staircase is the defining architectural element.
Structural Systems: What Supports the Treads
| System | Description | Visual Effect | Cost Premium |
|---|---|---|---|
| Mono-stringer | Single central steel beam | Treads appear to float | +15-25% over double |
| Double-stringer | Two beams along outer edges | Open, visible side framing | Base cost |
| Wall-mounted cantilever | Structural wall brackets | No visible stringer | Highest |
Open Riser vs Closed Riser
Open riser (no panel between treads): Light passes through, spaces feel connected, stringer design is visible. OBC minimum tread depth: 250 mm. The most specified configuration in current Ontario custom staircases.
Closed riser (panel between treads): Traditional configuration. Better for concealing storage and traditional interior styles. OBC minimum tread depth: 210 mm.
OBC Requirements by Staircase Type (Part 9 Residential)
| Requirement | Open Riser | Closed Riser |
|---|---|---|
| Minimum tread depth | 250 mm | 210 mm |
| Rise range | 125-200 mm | 125-200 mm |
| Max infill gap | 100 mm | 100 mm (balusters) |
| Minimum width | 860 mm clear | 860 mm clear |
→ Book a free C.O.R.S consultation – we evaluate your floor plan and recommend the right configuration.
Frequently Asked Questions
What is the difference between open riser and floating stairs?
Open riser means no vertical riser panel between treads. Floating describes the visual appearance of minimal visible support. A mono-stringer open-riser staircase looks floating; a double-stringer open-riser staircase is still open but has visible side framing. All floating staircases are open-riser.
What staircase type takes up the least floor space?
Spiral staircases have the smallest footprint (1,200-1,500 mm diameter) but are not recommended for primary residential use. For primary staircases, an L-shaped configuration in a corner is the most space-efficient practical choice at approximately 1,800 x 2,000 mm.
Do I need engineering review for a mono-stringer staircase in Ontario?
Yes. The single beam must be engineered to confirm beam size, connection details, and deflection under OBC design live load. C.O.R.S includes engineering review as standard on all mono-stringer projects. A stamped engineer’s letter is available for permit submissions.
What is the most popular staircase type in Ontario in 2026?
Straight open-riser mono-stringer with white oak treads and glass railing (where the floor plan allows), or L-shaped with the same specification for corner configurations. The layout choice is driven by floor plan constraints, not preference.
Related: Read our full Ontario Building Code staircase compliance guide →
Types of Staircases Ontario: Related Resources
- Floating staircase Ontario — complete guide to floating staircase types, OBC, and 2026 pricing
- Floating vs. traditional staircase Ontario — direct comparison with structural and cost details
- Custom staircase cost Ontario — cost by staircase type including straight, L-shaped, U-shaped, floating
- Staircase renovation Ontario — when to renovate vs. replace different staircase types
- Ontario Building Code staircase requirements — OBC specs that apply to every staircase type
- Staircase materials Ontario — tread species for every staircase type
Free consultation for any staircase type: 705-999-0000 | corsstairs.ca/contact
2 Responses