Replacing a Classic Staircase with a Central Stringer in Montreal
The classic closed staircase — two side walls, painted risers, a wood handrail — was standard in Montreal homes built through the 1990s and 2000s. It does the job. But in open-concept renovations, it becomes the one element that still closes off the space, blocks natural light, and dates the interior.
Replacing it with a steel central stringer changes all of that. A single steel spine runs down the center of the stair. Wood treads cantilever off both sides. The risers disappear entirely. Light moves through the staircase the way it moves through the rest of the floor. And the structure itself — the steel, the wood, the railing — becomes something worth looking at.
We do this transformation regularly across Montreal, Westmount, and the South Shore. Here's an honest breakdown of what it involves.
What is a central stringer staircase?
A classic staircase is built with two side stringers — diagonal structural members that run along each edge of the stair and support the treads from both sides. The result is a closed, box-like structure with risers filling the vertical gaps between steps.
A central stringer replaces both side stringers with a single steel spine that runs down the middle of the staircase. The treads cantilever outward from this spine on both sides. Without side walls or risers, the staircase is fully open — you can see through it, light passes through it, and the surrounding space reads as larger and more connected.
The central stringer is the perfect intermediate between a classic staircase and a fully floating design. It has the openness and visual lightness of a floating staircase, but at a lower price point and with broader structural compatibility — it works in more homes.
What the transformation actually involves
This is not a cosmetic renovation. Replacing a classic staircase with a central stringer is a full structural replacement that touches the floor, the ceiling, the walls around the stair, and sometimes the header above the stair opening. Here's the sequence:
1. Structural assessment
Before any design work begins, we assess whether your existing floor opening can accommodate the central stringer. Classic staircases are often built into a framed box that becomes part of the home's structure over time. We check the header above the opening, the joist configuration, and the bearing walls adjacent to the stair. In most Montreal homes this assessment confirms the transformation is straightforward. Occasionally, minor header reinforcement is needed — this is identified and costed before the project begins.
2. Demolition of the existing staircase
The old staircase is removed in full — treads, risers, side stringers, balusters, handrail, and the framed walls surrounding it if present. In homes where the staircase wall has drywall or plaster, this section will need patching and repainting after installation. Budget for that finish work as part of the overall project.
3. Steel fabrication
The central stringer is fabricated off-site based on precise measurements taken from your home — rise, run, floor-to-floor height, and opening width. The steel spine is typically a structural box beam or heavy plate section, powder coated to your chosen finish. Standard is matte black. This is the phase that takes the most time — fabrication typically runs 3–5 weeks depending on shop schedule and complexity.
4. Wood tread preparation
Treads are prepared in parallel with the steel fabrication. Wood species, thickness, edge profile, and stain are all selected at the outset. Each tread is cut to length, routed, sanded, and pre-finished before installation. Color matching to your existing hardwood flooring happens at this stage.
5. Installation
The steel spine is set first, anchored to the structural floor and header above. Treads are then bolted or welded to the spine. The railing system goes in last — whether that's steel pickets, horizontal steel bars, cable, or glass panels. Final finish and touch-up work closes the project.
| Configuration | Starting price (CAD) |
|---|---|
| Steel central stringer, wood treads, steel picket railing | From $11,000 |
| Steel central stringer, wood treads, horizontal steel railing | From $13,000 |
| Steel central stringer, wood treads, glass panel railing | From $15,000 |
| Above + structural modifications (header reinforcement, wall patch) | Add $1,500–$3,500 |
| Demolition and disposal of existing staircase | Add $500–$1,500 |
Choosing your wood species
The tread wood is the most visible material in the finished staircase. It's worth choosing carefully:
White oak — the most requested species in 2026 for modern and transitional interiors. Clean, neutral grain. Works with almost every interior palette.
Red oak — warmer tone, more pronounced grain. Common in Montreal homes — if your floors are red oak, matching is straightforward and cost-effective.
Maple — crisp and light. Best in very minimal, contemporary spaces.
Walnut — rich, dark, premium. Best when the staircase is meant to be a statement piece.
Choosing your railing
The railing is where the personality of the staircase lives. Three main directions:
Steel pickets — vertical balusters welded to a steel top rail. Classic, clean, works in any style. Most affordable custom option.
Horizontal steel bars — two or three horizontal rails between newel posts. Strong, contemporary, industrial-modern feel. Mid-range price.
Glass panels — frameless or spigot-mounted glass. Maximum openness and light. Best when the goal is to make the space feel as large as possible. Premium option.
Open risers and building code in Quebec
Central stringer staircases have open risers by design — there's no vertical face between the treads. In Quebec's National Building Code, open risers are permitted in single-family residential dwellings provided the opening between treads does not allow a 100mm (4-inch) sphere to pass through. In practice this means tread thickness and spacing need to be engineered correctly — something we handle as part of the design and fabrication process.
Confirm with your borough before starting any structural work. A licensed RBQ contractor will know the requirements for your area and can flag what approvals are needed before the project scope is finalized.
Ready to open up your staircase?
We design and fabricate steel central stringer staircases across Greater Montreal — from the initial structural assessment through to the final finish. Every project starts with a site visit and an honest conversation about what's possible in your space.
Request a free quote → or call us at 514-862-7786
