Custom Hardwood Stairs: Treads, Risers and Nosings from One Lot

The floor lands, the installer lays it, and it looks exactly like the sample. Then the stairs go in six weeks later — treads bought from a local joinery shop in the same species, because the flooring supplier "doesn't really do stairs" — and the colour is off by half a shade. Not enough to reject. Enough that every visitor's eye goes to it, because a staircase is the one horizontal surface in a house you look at from the front rather than from above.

That is the whole problem in one paragraph, and it is a sourcing problem rather than a carpentry one. Stairs are the part of a wood floor package that buyers treat as an accessory and factories treat as a different product. They are a different product: a tread is a structural member, a floorboard is not, and the two are cut, sized and code-checked differently. Get the stairs into the same order, from the same timber lot, at the same time as the floor, or accept that they will not match.

Here is what actually has to be specified, what the factory needs from your site before anyone cuts, and where building code — not the factory — sets the dimensions.

A tread is a beam; a floorboard is not

This is the engineering distinction that everything else follows from.

A floorboard is supported continuously along its whole length by a subfloor. It carries load in compression straight down into the deck. It can be thin because it never has to span anything.

A stair tread spans between two stringers — sometimes three, sometimes a centre carriage, sometimes nothing at all on an open-riser flight — with a person's full weight landing on the middle of it. It is a short beam. Stiffness in a beam scales with the cube of its depth, which is why a tread that is twice as thick is not twice as stiff, it is eight times as stiff, and why nobody makes treads out of flooring stock.

Two practical consequences buyers routinely miss:

Engineered flooring does not become a tread by getting thicker. Cut an engineered board to tread size and the front edge exposes the core layers at exactly the place your eye lands and your foot lands. On engineered floor projects, treads are normally solid, or a solid tread with a matched face — which means the tread has to be produced deliberately to match the floor, not cut from it.

Riser and tread are different materials problems. Risers carry almost no load and are usually thinner stock. Treads carry everything. Quoting them as one line item at one thickness is a sign the quote has not been engineered.

Ask the factory for the section thicknesses it actually offers for treads, and ask separately whether a wide tread is a single board or glued up from several staves. Both answers are legitimate — a glued-up tread is often more stable than a single wide board, because opposing grain directions cancel movement — but you need to know which you are buying, and a glued-up tread has visible joints that must be arranged deliberately rather than randomly.

Nosings: where building code, not the factory, decides

The nosing is the projecting front edge of the tread. It is the most regulated component in the whole package, and the regulation varies by jurisdiction, which is why factories rarely volunteer a profile — they are waiting for you to tell them.

In the United States, residential stairs are typically governed by the International Residential Code as adopted (and amended) locally. The IRC provisions that drive the timber are the ones on nosing projection and leading-edge radius, on maximum riser height and minimum tread depth, and — the one that catches importers — on uniformity: the difference between the tallest and the shortest riser in a single flight is tightly capped, on the order of a fraction of an inch. In England and Wales, Approved Document K sets rise and going ranges and a maximum pitch instead, with the familiar twice-the-rise-plus-the-going relationship. Elsewhere, national annexes to the EN stair standards do similar work with different numbers.

Do not take those values from an article, including this one. Take them from the edition your local authority has actually adopted, confirm them with the building official or the project architect, and then hand the factory a drawing with dimensions on it, not a code reference. A factory in Guangdong cannot read your county's amendments, and it should not be asked to.

What you do need from the factory is which profiles it can cut:

• Square nosing — no overhang, contemporary, easiest to make, not permitted in every jurisdiction on closed-riser stairs.
• Bullnose / half-round — full radius on the projecting edge.
• Radiused or eased edge — a defined small radius, which is the shape most codes constrain.
• Double-radius / pencil round — radius top and bottom of the projection.
• Mitred return nosing — the tread's nosing profile carried around the open end of the tread, mitred so no end grain shows. This is the detail that separates a joinery-grade stair from a kit, and it has to be specified per tread because only the open ends get it.

Why the same lot is the only colour match that works

Species does not equal colour. Two black walnut orders, same grade, same mill, six weeks apart, will differ — different logs, different growth regions, different kiln charges, different sapwood share. The variation is normal timber behaviour, not a defect, and no supplier can promise it away.

A penetrating oil finish makes the difference more visible rather than less, because it saturates the wood and reports whatever colour is underneath, where a pigmented film coating can be used to level colour out. If you are buying an oiled floor — and hand-rubbed oil is the reason a lot of buyers go to a workshop like this in the first place — the one-lot rule is not a nicety.

So the sequence is: specify the floor and the stairs and the trim in a single order, cut from a single timber lot, finished on the same schedule with the same oil batch. Any factory that lists floors and stairs together should be able to confirm that in writing. Anrantabu Flooring's capability listing describes staircase treads, risers, nosings, handrails and balustrade components produced from the same timber lot as the main floor precisely so grain and colour match throughout, at a stated volume of roughly 1,000 custom staircase sets a year from its 20,000 m² Huiyang plant. Treat a listing as the starting point for a conversation, not as a spec: confirm on the PO that your treads and your floor are drawn from one lot, name the lot, and ask for the timber to be reserved before production begins rather than at the point the stairs are scheduled.

The same argument applies to texture. If your floor is hand-worked, the treads have to be worked by the same hands to the same standard — see specifying scraped and relief-carved texture for how to write that down so it survives to the stair run.

The site survey the factory needs before anyone cuts

Stairs cannot be quoted from a floor area. This is the checklist to complete before you ask for a price, and the order in which to complete it.

1. Stair type. Straight flight, quarter-turn with landing, half-turn, winder, open riser, curved. A winder or curved stair is a template job, not a measurement job.
2. Total rise, measured three times. Finished floor to finished floor, taken at the top, middle and bottom of the flight. If the three numbers disagree, the building has settled and the risers cannot all be equal.
3. Number of risers, and every individual rise on a retrofit. Not the average — each one. This is where the uniformity rule bites.
4. Clear width between stringers, measured at top, middle and bottom. Walls are not parallel. Assume they are, and the bottom treads bind or the top treads leave a gap.
5. Housed or surface-mounted. Are treads let into a routed housing in the string, or do they sit on top of cut stringers? Housed treads need a length allowance for the housing depth at each end.
6. Open ends, left or right. Which treads need a return nosing and on which side.
7. Finished floor thickness at the top landing, and floor build-up at the bottom. The single most common retrofit error: the top riser height changes with the thickness of the floor above it, and the bottom riser changes with whatever goes over the slab. Order every riser the same height and you will fail a code inspection at both ends of the flight.
8. Handrail and balustrade scope. Timber only, or metal components too? Wall-mounted or newel-supported? Baluster spacing is code-driven and depends on the tread depth.
9. Existing carriage or new-build. If the stair carcass already exists, the factory is cladding it and the tolerances are the building's. If it is being built to the kit, the tolerances are the drawing's.

Photograph everything, dimension the photographs, and send a marked-up drawing rather than a paragraph of prose. This is the same discipline that makes a product spec sheet for a Chinese factory work: numbered lines, one fact per line, a drawing where a drawing beats words.

The PO table

Three details worth knowing before you negotiate:

• Ask for a numbered kit and a matching layout drawing. A crate of correctly made treads with no numbering and no drawing is a puzzle your installer will bill you to solve. Numbering without a drawing is no better.
• Ask where the moisture content is measured and to what target. Treads are thicker than flooring, so they dry more slowly and hold a wetter core. A tread shipped at floor-appropriate moisture content on the surface can still be moving inside for weeks after installation.
• Stairs are the most damage-prone item in the container. Long, heavy, with a machined edge that defines the whole product — the nosing. Specify edge protection on the nosing specifically, not just "carton packed", and read packing and shipping protection practice before you accept a packing list.

Common questions

Can I order stairs after the floor, from the same factory?

You can, but the colour match is then a matter of luck and remaining stock. If the timber lot that produced your floor is gone, the factory is matching from a different lot, which is the same problem as ordering from a different supplier with a friendlier accent. If phased delivery is unavoidable, buy the stair timber with the floor and have the factory hold it.

Do stair treads need slip-resistance testing?

For residential work, usually not. For hospitality, retail, offices and anything with a public-access classification, frequently yes, and the specifier will ask for it. Request test data on the finished surface — the oil or lacquer is what your foot touches — under whichever method your market uses, commonly a DIN 51130 R-rating or an EN 16165 pendulum test. Ask what data exists rather than assuming it does, and ask which finish it was run on.

Is a glued-up tread inferior to a single board?

No, and often the opposite. A wide single board carries more movement across its width and is more prone to cupping. A glued-up tread with alternated grain is more dimensionally stable. What matters is that the stave layout is designed rather than random, and that you approve it on a sample.

How far ahead do I need to order?

Further than the floor. Stairs need the site survey completed first, and the survey usually cannot happen until the structure is up and the finished floor levels are fixed. Build the survey into the programme as a dated milestone, not as something the installer does when he arrives.

What to ask the supplier next

1. Do you manufacture staircase components in-house to a buyer's drawing, or through a partner workshop? Please confirm in writing on the PO.
2. What tread section thicknesses do you offer, and at what width does a tread become glued-up rather than single-board?
3. What is the maximum finished tread length you can produce, and the maximum you can pack for sea freight?
4. Which nosing profiles are standard, and can you cut a profile from my dimensioned drawing?
5. Will you confirm on the order that floor, treads, risers and nosings are cut from one named timber lot and finished on one schedule?
6. Do you issue a site-survey template, and what does it ask for?
7. Does the kit ship numbered, with a layout drawing that matches the numbers?
8. What slip-resistance data exists on the finished tread surface, and on which finish was it produced?
9. Is balustrade scope timber only, or do you supply metal balusters and fixings?

Anrantabu Flooring is one place to run that list: a custom handmade solid wood flooring maker in Huiyang, Huizhou since 2005, whose stated scope covers staircase systems alongside the floor itself, with timber drying, cutting, hand-sanding and multi-coat hand-rubbed oil finishing carried out on one site. Whether it fits your project comes down to the nine answers above — get them in writing before the timber is cut, not after.