6 min read · · by Luke Adkins
What Building a Curved Staircase Actually Involves
The curved white oak staircase on this site gets more questions than anything else. Most of them are some version of “how.” This is the answer.
It starts with what is under the carpet
Most builder stairs are two-by-twelve stringers with plywood or particleboard treads, carpeted. If the stringers are sound and the rise and run are legal, they stay. If a stringer is cracked or the rise is uneven by more than a quarter inch, the flight gets rebuilt. This is decided in the first hour.
Treads and risers are made, not bought
Solid white oak treads are milled to a consistent thickness, bullnosed on the front edge, and cut one at a time to the actual width of each step, because no two are the same in an old house. Risers are oak or paint-grade depending on the look. Everything gets dry-fit before glue.
The curved starter step
The flared bottom step that wraps around the newel is the piece that makes the stair. It is built up from laminated strips bent around a form, or cut from a wide glue-up and shaped, then bullnosed to follow the curve. It takes as long as the rest of the flight.
Railing last
Newel posts get anchored through the floor to framing. Balusters, wood or metal, are set on a layout that lands evenly at both ends. The handrail is fitted in sections and joined with rail bolts. A railing that wiggles is a railing that was not through-bolted.
Finish on site
Sanding to 120 grit, then a stain or a natural finish chosen against the floor in the room’s actual light, then two or three coats of a water-based matte finish. The stair is off limits for about 24 hours per coat.
Time and cost
Two to four weeks for a full flight. What moves the price is the number of treads, the curved step, the railing style and whether the stringers are reused. Ask for the quote broken out that way.