Stair Parts & Terminology, Explained
Staircase terminology gets confusing fast — baluster, spindle and picket often mean the same thing, and "banister" gets used for at least two different parts. Here's what each term actually refers to, in plain language, so you know exactly what you're asking for.
Last checked against current official sources: . This page is a general reference, not legal advice — requirements depend on the specific project and your local building authority.
Baluster vs. spindle vs. picket
These three terms mostly describe the same thing: the vertical pieces that fill the gap under a handrail. "Baluster" is the formal, code-standard term (it's what the Ontario Building Code uses, and what "balustrade" is built from). "Spindle" is the common everyday term, and often implies a turned, decorative shape rather than a plain square or round bar. "Picket" is borrowed from fencing and shows up less often for stairs, but you'll hear it used the same way in casual conversation. If someone asks for "new spindles" or "new balusters," they're almost always asking for the same job.
Newel post
The newel post is the main, sturdier post anchoring the railing — at the bottom of the stairs, the top, and at any landing or direction change. It's what the handrail physically attaches to and what the whole guard system's structural strength depends on, which is why a loose or rotted newel post is a real safety issue, not just a cosmetic one.
Handrail vs. railing vs. guard
These three get used interchangeably in everyday speech, but they mean slightly different things. The handrail is specifically the graspable rail you hold for support while walking the stairs — it has its own height requirement (see our Ontario Building Code guide). The guard is the code term for the whole protective barrier that keeps someone from falling off the open side of a stair, landing or balcony — that's what the guard-height and baluster-spacing rules apply to. "Railing" is the informal umbrella term most people use for either or both. A banister (see below) usually means the handrail specifically, sometimes the whole assembly.
Banister / bannister
Both spellings are correct — it's just a regional/informal variant. "Banister" most often refers to the handrail, though plenty of people use it to mean the entire railing assembly (handrail, balusters and newel posts together). It's not a term the building code uses; "handrail" and "guard" are the precise terms if you're checking something against code.
Tread, riser and nosing
The tread is the horizontal part you step on. The riser is the vertical piece between two treads — some modern designs use open risers (no vertical piece at all, so you can see through the stairs), though the current Ontario Building Code restricts where that's actually permitted. The nosing is the tread's front edge, which projects slightly past the riser below it — it's also the reference point the code measures rise, run and headroom from.
Stringer
The stringer is the structural side member that the treads and risers sit on and attach to — think of it as the staircase's skeleton. A straight-run stair typically has two (one on each side, sometimes a third down the centre for a wide stair); a curved or winder staircase has stringers that change shape at every step, which is why those cost more to build.
Balustrade
The balustrade is the complete railing system as a unit — newel posts, balusters and handrail together, not any single piece of it. If someone asks to "replace the balustrade," they mean the whole railing, not just the handrail or just the spindles.
Recapping vs. refinishing vs. rebuilding
Recapping (also called capping) installs new tread and riser material over the existing stringers, without touching the structure underneath — see our capping-vs-replacement guide for when that works and when it doesn't. Refinishing sands and reseals or restains the existing treads and risers themselves, with nothing replaced — only realistic when the wood underneath the wear is still structurally sound. Rebuilding (full replacement) removes the staircase down to the stringers and starts over, which is the only option when the structure itself — not just the surface — is the problem.
Frequently asked questions
Is a spindle the same thing as a baluster?
In practical terms, yes — they refer to the same vertical infill pieces under a handrail. "Baluster" is the term you'll see in the building code; "spindle" is what most homeowners say, often specifically for a turned, decorative shape rather than a plain bar.
What's the actual difference between a handrail and a guard?
The handrail is the part you grip for support — it has its own height range under the Ontario Building Code. The guard is the broader fall-protection barrier (the handrail, balusters and structure together) that has its own separate height and opening-spacing rules. Most people say "railing" and mean either or both, but the code treats them as two distinct things with two distinct requirements.
Why does my staircase have three different post sizes?
The larger, sturdier ones at the bottom, top and any landing or turn are newel posts — they carry the real structural load of the railing. Anything thinner and more decorative in between is a baluster or spindle, which fills the gap but isn't meant to bear the same load.
Can I just replace the balusters without touching the handrail?
Yes, if the handrail itself is solid and you just want an updated look or need to bring spindle spacing up to code — see our stair posts & spindles service for exactly this. The handrail and balusters attach independently, so one can be replaced without the other.
How do I know if my stairs need recapping, refinishing, or full replacement?
It comes down to what's actually worn: if only the surface finish is tired but the wood underneath is sound, refinishing is usually enough. If the treads themselves are worn through or you want a different material without touching the structure, recapping is the middle option. If the stringers or structure are damaged or out of level, that's a full rebuild — we'll tell you plainly which applies to your stairs during the site visit, not guess from a photo.