Before choosing a basement floor, check the stairs against the proposed finished floor heights. The subfloor, flooring and stair finishes need to be planned together. Raising the basement floor can shorten the bottom step, while new stair coverings or changes to the upstairs floor can alter the first or last rise. Those changes also need to be considered alongside landings, doors and overhead clearance.
For a Niagara homeowner, this is a useful early design check, before ordering flooring or closing in the stairwell. A floor that looks right on a sample board still has to work where it meets the stairs.
Count the whole floor assembly
The thickness printed on a flooring box is only part of the finished height. Depending on the proposed system, the build-up above the concrete may include levelling material, a moisture-control layer, insulation, subfloor panels, underlay, adhesive and the floor finish itself.
Not every basement needs every layer. The combination should suit the slab conditions and the selected products. Ask for the complete proposed assembly, with its expected finished elevation at the bottom of the stairs, rather than relying on the flooring thickness alone.
Also identify which existing materials will be removed. Replacing one finish with another is different from installing a new system over what is already there. If levelling is needed, the added thickness may vary across the room.
Why the bottom and top steps deserve extra attention
A stair riser is the vertical change between successive walking surfaces. If the basement floor moves upward while the first tread stays where it is, the bottom rise becomes smaller. The middle steps do not change simply because the basement floor has changed.
Covering the stairs introduces another relationship. Adding the same thickness to every tread can leave the middle rises unchanged, yet alter the connections to the floors at either end. The outcome depends on what is added or removed at the bottom landing, each tread and the top landing.
That is why “we will cover every step equally” is not a complete stair plan. Ask for the whole flight to be reviewed using its proposed finished surfaces.
Ontario’s 2024 Building Code, Part 9, includes requirements for riser dimensions and uniformity within a flight. A contractor or qualified designer should establish which provisions apply to the project, rather than assuming the existing stair will remain acceptable after the floor changes.
Include the landings and nearby doors
The bottom of the stair often becomes a busy junction: a family room ahead, laundry to one side and a storage or mechanical-room door nearby. New walls and cabinetry can change how that area works even when the stair itself stays in place.
Review the layout with doors shown open, not just as lines on a floor plan. Include finished wall thicknesses and any transition between the new basement floor and adjoining unfinished space. Look at where someone will stand to open a door or turn toward another room.
Part 9 addresses required landings, landing dimensions and door swings toward stairs, with exceptions that depend on the arrangement. The landing provisions should be checked against the actual design.
A door rubbing against new flooring is only one possible issue. Moving the door, changing its swing or trimming it should not be treated as an automatic solution without reviewing its purpose and the surrounding clearances.
Check headroom with the finishes included
Floor height and ceiling height belong in the same conversation. A raised landing reduces the space below the ceiling above it. Stair coverings raise the tread surfaces, while a new ceiling or boxed-in duct can lower the overhead surface.
Have the proposed stair and landing clearances checked at the tightest locations, including the stair opening and any nearby beam or bulkhead. A room-height measurement taken in the middle of the basement does not answer the stair-headroom question.
The Code specifies how clear height over stairs is measured and includes provisions for particular stair and building conditions. See Part 9, Articles 9.8.2.2. and 9.8.6.4. for the stair and landing requirements.
If the ceiling design is still open, review drywall versus drop ceilings for a Niagara basement before settling the finished heights.
Existing stairs need a project-specific code review
An older staircase should not be judged from a single new-construction measurement found online. Ontario’s Division A application provisions address the use of Part 11 for buildings that have existed for at least five years.
Part 11, Renovation, contains requirements for changes to existing buildings and compliance alternatives for specified circumstances. It is not a blanket exemption for an old stair. Ask the designer and municipal building department how the proposed work will be assessed, particularly if the basement’s intended use is changing.
Permit scope matters too. The City of Niagara Falls lists finishing or partially finishing a basement among projects requiring a building permit, while listing some minor flooring installations separately. Confirm your complete renovation scope with your own municipality before work begins.
A practical sequence before ordering flooring
- Document the existing stair. Have the full flight, both landings, nearby doors and overhead obstructions measured and recorded.
- Choose the proposed assemblies. List what will be removed and added at the basement floor, stair treads, top landing and ceiling.
- Review the finished geometry. Ask for the end rises, remaining risers, landing space, headroom and door operation to be checked together.
- Resolve conflicts before finishes are purchased. Compare suitable assembly and layout options with the contractor or designer. Any structural changes need appropriate design and approval.
- Recheck when selections change. A different subfloor, stair covering or ceiling detail can change the measurements. Keep the current selections with the project drawings.
Include service access in that review. Our guide to basement utility access before framing covers another set of details worth resolving before walls and finishes go in.
Frequently asked questions
Can I keep the existing basement stairs?
Possibly. Their condition, geometry, proposed finishes and applicable renovation requirements need to be reviewed first. Keeping the stair does not mean the surrounding floor heights can be changed without checking the result.
Will thinner flooring solve an uneven bottom step?
It may change the amount of height added, but the complete assembly matters. Have the proposed finished elevations compared before selecting a product as the solution.
Should flooring or stair finishing come first?
Plan both together, then agree on the installation sequence. The important early decision is the finished height at every connection, not which trade arrives first.
Plan the stair connection early
Planning a basement renovation in Niagara? Contact Homes By Adam to discuss the layout, flooring choices and stair connection before finalising the scope. Bringing those details together early gives you a clearer plan for the finished space.
This article provides general planning information. Confirm project-specific code requirements, permits and any necessary design work with qualified professionals and your municipal building department.
