Custom Staircase Construction

Where a new stair comes into a project

A new staircase is rarely a project by itself. It is usually the piece that makes another project work: an attic becoming bedrooms, a basement becoming living space, an addition that needs its own way up, or a reworked first floor where the old stair sits in the wrong place. In each case the stair takes floor space on two levels and a hole through the floor between them, so its location shapes every room around it.

That is why we place the stair early in the design. We look at where it lands at the bottom and whether there is room to step off it, where it arrives at the top and whether that leaves a usable hall, and whether it passes under a roof slope or a beam that steals headroom. Those questions are far easier to settle on paper than after the opening is cut.

If you are keeping your stair where it is and updating how it looks and feels, that is staircase remodeling, which has its own page.

Framing the opening in the floor above

A stair needs a hole through the floor above, and that hole cuts joists. The cut joists have to hang from doubled headers, and the joists along each side of the opening are doubled to carry the extra load. In an older house we look at which way the joists run, whether the opening runs with them or across them, and what sits on that floor. An opening across the joists is a much bigger structural change than one that runs along them.

For attic conversions in particular, the existing ceiling joists may be too small to serve as a floor at all, and the stair opening is only one part of reframing that floor. An engineer sizes the headers and any new joists when the loads call for it, and the framing is inspected before it is covered. Steve's unrestricted Construction Supervisor License covers supervising this kind of structural work on one- and two-family homes in Massachusetts.

Cutting an opening in an occupied house takes setup. Temporary supports go under the joists before any are cut, the floor above is cleared and protected, and the area is sealed off from the rest of the house, because cutting through a plaster ceiling makes fine dust. In houses built before 1978, that setup follows lead-safe practices. You know the day the opening gets cut and what the house looks like until the stair is in.

You know the day the opening gets cut and what the house looks like until the stair is in.

Laying out rise, run and headroom

Every step on a stair has to be the same height, within a very small tolerance, and the same depth. We start from the exact finished floor-to-floor height, including the finish flooring on both levels, divide it into equal risers inside the code limits, and then work out tread depth and total run. A stair built to the wrong finished heights shows up as a short first or last step, and people trip on it for as long as the house stands.

Headroom is the other number that can sink a layout. The code sets a minimum clear height measured above the stair along its whole length, and in Capes, attics and basements a roof slope, a beam or a duct often gets in the way. Sometimes the answer is moving the stair a foot, turning it, or rerouting the duct. We find those conflicts during layout, not on inspection day.

The building code under 780 CMR also sets handrail height, guard height along open sides and baluster spacing, and those are designed in from the start rather than added at the end.

Landings, winders and turns in tight houses

Straight runs are the simplest to build and to use, but many New England houses cannot spare the length. An L-shaped or U-shaped stair with a landing fits a shorter footprint and gives a place to pause halfway. Winders, the pie-shaped steps that turn a corner, fit in even less space and are common in older Capes, but they carry their own code requirements for tread depth along the walking line and need careful layout to feel comfortable underfoot.

We frame landings as their own platforms tied into the walls, cut stringers from stock suited to the span, and support long runs at the middle where needed. Basement stairs bring moisture and concrete into the picture, so stringers that bear on a slab sit on a treated plate or a barrier rather than bare wood on concrete.

Some locations bring extra requirements. A basement stair needs lighting switched from the top and the bottom, and the space under any stair that is enclosed as a closet needs its walls and underside covered the way the code requires. Our licensed electrician handles the switching, and we frame for it before the walls close.

Rough stair first, finish stair last

We usually build a new stair in two stages. The rough stair goes in early with temporary treads so our crew and the trades can get up and down safely during the rest of the job. Finish treads, risers, skirt boards, the rail and the balusters go on near the end, once the heavy traffic that would scratch them is over.

A new stair also has to tie into the house visually. Where it meets existing floors, we lay in nosings and transition boards so the edge of the opening looks finished, and the skirt boards are scribed tight to the wall. Small details, like the return at the end of an open tread or the height where the handrail starts, decide whether the stair looks built in or added on.

Finish choices are yours: oak or maple treads, painted risers, a box newel or a turned one, a handrail profile matched to the rest of the house. Through the whole process you know where the stair stands in the schedule, and if the framing above turns up something unexpected, you hear about it the same day along with what it changes.

See the rest of our structural work, or browse the gallery for rooms we have finished.