A staircase is the only element in a house that has to work structurally, spatially, and visually at the same time. It carries people between floors, it occupies a footprint on both of those floors, and because it usually sits in the entry or the centre of the plan, it is one of the first things anyone sees. Very few components have to do that much at once.
That is why staircase work splits so cleanly into two very different projects. Refinishing treads, replacing balusters, and changing a handrail is finish carpentry with a code review attached — the stair stays exactly where it is. Moving a stair, changing its run, or opening a closed stair into the room is structural: the floor opening changes, headroom changes, and framing on two levels is affected. Homeowners frequently arrive wanting the second while budgeting for the first.
Six components do almost all the work, and knowing which one you are talking about is most of what makes a stair conversation productive.
The horizontal surface you step on and the vertical face between steps. Their dimensions are code-regulated, and crucially they must be consistent from step to step — uneven risers are a trip hazard and one of the most common failures found in stairs that were rebuilt without the geometry being recalculated. On an existing stair, retreading is a finish change; altering the dimensions is not.
The sloped members carrying the treads. A closed stringer runs as a solid board with the treads housed into it; an open stringer is cut so the tread ends are visible from the side. This is the single decision that most changes how a stair looks, and on an existing stair it usually cannot be swapped without rebuilding the stair.
The barrier protecting the open side of a stair, landing, or floor opening. Guards are a safety element with height and infill requirements set by code, and their attachment matters as much as their appearance — a guard has to resist real force, which means the framing behind it has to be capable of receiving it.
The graspable rail you actually hold. It is distinct from the guard even when it is mounted on one, and code addresses its height, its continuity, and its shape — a handrail must be graspable, which rules out some otherwise attractive profiles. Handrails are the element most often compromised for looks and most often failed at inspection as a result.
The vertical clearance measured above the stair. It is regulated, and it is the requirement most likely to constrain a stair move: relocating a stair or changing its run changes what is above every step, and a ceiling, a beam, or a floor edge that was clear before may no longer be.
The posts anchoring the railing system and the vertical infill between them. Newels are structural to the railing — the whole system depends on them — while baluster style, spacing, and material are largely aesthetic within the infill limits the code sets for openings.
The line is clearer on stairs than on almost any other interior element: if the stair stays where it is and its geometry does not change, you are in finish territory. The moment either of those moves, you are not.
Finish work — stair stays put
- Refinishing or replacing treads and risers within the existing geometry.
- Replacing balusters and infill within the existing railing framework.
- Replacing or refinishing a handrail on the same mounting.
- Carpet removal, staining, painting, and skirt-board detailing.
Structural — framing changes
- Moving the stair, or changing where it lands on either floor.
- Changing the number of steps, the rise, or the total run.
- Enlarging or reshaping the floor opening the stair passes through.
- Opening a closed stair into a room by removing an adjacent wall.
- Adding a landing, changing a straight run to a turn, or the reverse.
Opening a closed stair into a room is the crossover case, and it is the one most often underestimated. If the wall alongside the stair is carrying load, that is a load-bearing wall removal with a beam, posts, and a load path — plus a new guard and railing system along the newly open side.
Stair, guard, and handrail requirements are specified in the California Building Standards Code and are enforced — and sometimes amended — by your local jurisdiction. They cover tread depth, riser height and consistency, headroom, guard height, the size of openings in guard infill, handrail height, handrail continuity, and handrail graspability.
We deliberately do not publish specific inch measurements here. Those dimensions differ between residential and commercial provisions, they differ between code cycles, and local amendments can modify them. A number quoted from memory is a number from some code somewhere, and stairs are exactly the wrong place to be approximately right. Your building department is the authority on what applies to your permit on the date it is issued.
What is worth knowing in advance is the shape of the requirements rather than their values: consistency between steps is enforced tightly, guards and handrails have to withstand force rather than merely exist, headroom is measured along the stair rather than at one point, and an existing non-conforming stair is generally allowed to remain as it is — but rebuilding it usually means bringing it into current compliance.
The code California enforces is published by the California Building Standards Commission, adapted from the model codes of the International Code Council. Local amendments sit on top of that, which is why your city or county building department — not a web page — is the authority for your project.
Closed stringer — the traditional look
The stringer runs as a continuous board and the treads are housed inside it, so the side of the stair reads as a clean sloped plane. It is the more forgiving construction, it hides small variations at the tread ends, and it suits traditional and transitional interiors. In older Northern California homes it is usually what is already there.
Open stringer — the exposed look
The stringer is cut to the profile of the steps and the tread ends are visible, often returned with a moulded nosing. It reads lighter and more crafted, and it is the setup that allows balusters to land directly on the treads. It also demands far more precision, because every cut is on display.
Open riser — the contemporary version
Treads with no riser between them, so light passes through the stair. Visually striking and popular in modern and mid-century interiors, but the open space between treads is regulated for safety, which limits how open the stair can actually be. That is a design constraint worth understanding before it becomes a disappointment at plan check.
The railing decision follows the stringer
Whether balusters land on treads or on the stringer is determined by the stringer type, and that in turn shapes the whole railing design. Wood, metal, cable, and glass systems each have their own attachment and infill considerations, and all of them still have to satisfy guard and handrail requirements — a cable or glass system is a material choice, not an exemption.
Whichever configuration you choose, the finish detail around the stair — skirt boards, tread returns, newel proportion, and how the rail meets the wall — is what separates a stair that looks built from one that looks assembled. The same principles are covered in our guide to trim and millwork.
- 01Assessment — we look at the existing stair, its framing, the openings on both floors, and what is above and below it.
- 02Scope split — we separate what is genuinely finish work from what changes geometry or framing, because those two carry very different requirements.
- 03Design and code review — the proposed geometry is checked against what your jurisdiction enforces before anything is built.
- 04Structural engineering, if the floor opening or framing changes — beams, headers, and connections are specified and stamped.
- 05Permit — required for structural work and often for regulated non-structural changes as well.
- 06Build — framing and stair construction, then guard and handrail installation with attention to how the guard is anchored.
- 07Inspection and finish — the building department inspects, then treads, risers, and railings are finished.
One practical note on living through it: a staircase is usually the only route between floors, so unlike most interior work it cannot simply be closed off and worked around. Sequencing matters more here than almost anywhere else in the house, and it belongs in the schedule conversation from the start. The broader picture of how interior structural work sequences is in the structural interior changes hub.
Do I need a permit to remodel a staircase?
It depends on what is changing. Refinishing treads, replacing balusters within an existing framework, or restaining a handrail is typically finish work. Changing the geometry — the rise, the run, the number of steps — or altering the floor opening, moving the stair, or replacing a guard or railing system generally requires a permit, because stairs, guards, and handrails are safety elements the building code governs closely. Because a stair project often turns out to be larger than it first appears, we confirm the permit path with your jurisdiction before work starts rather than mid-project.
What are the code requirements for stair treads, risers, and handrails?
They are set out in the California Building Standards Code and can be amended locally, and they cover tread depth, riser height and consistency, headroom, guard height and infill openings, and handrail height, continuity, and graspability. We do not publish specific measurements because they differ between code cycles and jurisdictions, and stairs are the wrong place to be approximately right. The reliable answer is the code cycle your building department is enforcing on the date your permit is issued, and the design is checked against it before anything is cut.
When does a staircase change become structural work?
The moment the floor opening or the stair framing changes. Moving a stair, changing its run or the number of steps, adding or removing a landing, or opening a closed stair into an adjacent room all affect framing on one or both floors, and enlarging the opening a stair passes through means headers and possibly beams. Headroom is the constraint that catches people out — relocating a stair changes what sits above every step, and clearance that was fine before may not be. Anything in this category needs engineering and a permit.
Can I change a closed staircase to an open one?
Often yes, and it is one of the highest-impact interior changes available, because an enclosed stair released into a room transforms both the stair and the space around it. What it involves depends on the wall being removed: if that wall carries load, this is a load-bearing wall removal with a beam, posts, and a load path, and in California it is also evaluated for lateral resistance. A new guard and handrail system will be required along the newly open side, and the stringer type may need to change to suit it. It is a real project, not a demolition afternoon.
Are open-riser and cable railing stairs allowed in California?
Both are used in California homes, but neither is exempt from the safety requirements. Open risers are regulated for the size of the opening between treads, which limits how visually open a stair can actually be. Cable and glass railings still have to meet guard height, infill opening, and load requirements, and cable in particular has to be tensioned and detailed so the spacing holds over time. These are material and design choices operating inside the same rules as any other railing — worth confirming during design rather than at plan check.
Does my old staircase have to be brought up to current code?
An existing stair that was legal when built is generally allowed to remain as it is. What changes the picture is rebuilding it: once you alter the geometry, replace the railing system, or reframe the opening, that work is normally expected to comply with current requirements. This is why the scope split matters so much on stairs — a project that starts as refinishing can cross into compliance territory depending on exactly what gets replaced. Your building department makes the call, and it is worth asking before demolition rather than after.
Planning a staircase remodel in Sacramento, Roseville, or anywhere across Northern California? We check the geometry against what your jurisdiction enforces before anything is cut. Request a free estimate
The following government agencies, industry organizations, and official resources provide additional information relevant to your remodeling project.