Stair systems
Layouts
Residential
Straight mono stringer →Cable & metal
Wood & combinations
Frameless glass →Tread profiles
Solid white oak →Stair lighting
Light under every tread →Who we work with
Stair systems
Mono stringer
Layouts
By material
Residential
Commercial
All floating stairs →Tread materials
Wood species
Tread profiles
Finishes
Who we work with
Work with us
Specifications
The turn, without stopping.
Two flights on central steel spines that turn 90° on three tapered winder treads instead of a landing. One slim post holds the corner. The most compact way to turn a floating stair, engineered, permitted and installed in NYC, Long Island and New Jersey, from $34k in NJconfirm.
A winder mono stringer is an L-shaped stair without the landing. Three tapered treads fan around the corner, so you keep climbing through the 90° turn. Both central steel spines meet on one slim post, and each winder sits on its own steel arm welded to that post.
The winder post · two spines, three arms, shop-welded steel
The fan of winders is where this stair shows its craft. The details people notice first.
The corner decides how the stair walks, where the structure goes and how much floor it takes. The line is the path your feet follow.
Three tapered treads carry you around the corner without stopping. It saves about one tread of floor in each direction. Code sets the shape: at least 10″ deep on the walking line, 12″ from the narrow end, and never less than 6″, so the winders fan from a small open eye at the inside corner.
A level square between the flights. You stop, turn, and keep going. Every tread is a full 11″, so the stair walks the same from bottom to top. The landing needs its own support: a slim post, or the wall beside it.
Both plans: 10′ floor to floor, 42″ treads, 7½″ risers. Configuration is confirmed against your space and the code that applies there.
The winder arms, the post, the glass and the handrail are drawn together as one design, not added on site.
Both spines meet on one 4″ square post. Three short steel arms are welded to the post at three heights, one under the centre of each winder, so every winder is carried like a tread. The post takes the corner straight to the floor.
On the open side the panels step with the winders and turn the corner as separate flat panels, set ½″ apart, so nothing bends in the air. 36″ above the nosings in NJ and on Long Island, 34″ along the flight in NYC.
On the wall side the handrail follows the winders around the corner and up the second flight in one line, 34–38″ above the nosings, so your hand never has to let go at the turn.
Pick your floor height, where the winders sit and which way you turn. The plan and the numbers redraw to the same rules our engineer uses.
Under the winders there is about 3′-2″ clear at the corner post: not enough to walk under, enough for a bench or a planter.
A straight mono stringer needs only its two ends. A winder stair has three supports: the floor, the post at the corner and the upper floor. Tap a step to follow the weight.
Reactions are for a typical 10′ winder stair in white oak and are illustrative. A licensed PE sizes every connection for your stair and your floor.
| Component | Specification |
|---|---|
| Spines | Two closed steel tubes, HSS 10×6 typical, both welded to the corner post |
| Winder arms | Three short steel arms moment-welded to the post, one under each winder, with seat plates |
| Corner post | HSS 4×4 typical on a ¾″ plate with 4 anchors |
| Winders | 3 × 30°, 3¾″ solid wood, ≥ 10″ deep on the walking line, ≥ 6″ at the narrow end |
| Treads | 42″ × 11″ × 3¾″, 18″ past the spine each side |
| Rise × run | 7–7½″ × 11″, about 33°. Open riser gap ≤ 3¾″ |
| Top | ¾″ header plate, through-bolted. A moment connection, not a hanger |
| Loads | 40 psf, plus 300 lb on any tread or winder |
| Stiffness | L/480 per flight, first frequency 8–10 Hz or more |
Choose the tread species, the spine finish and the lighting as one coordinated palette. The winders are cut from the same boards as the treads.
Matte black
White
BronzeAn LED channel under the nose of every tread and winder, wiring hidden inside both spines and the post, one dimmable driver. Motion sensors and tunable white are options. +$1.5–4k.
Your electrician brings power to one box at the base of the post. We do the rest.
Under-tread stair lighting →The railing sets how open the stair feels and what your hand holds. Guards are coordinated across both flights and the winders, and the handrail stays continuous at the turn.
Gaps under 4″ everywhere. All railings → · Glass railings → · Cable railings →
One geometry. Change the wood, the spine and the railing, and the room changes with it.
Floor height and width, where the winders sit, tread species, railing, finishes, lighting and site conditions.
See prices ↓One more day than a straight stair: the post and its winder arms go in first, then each flight. Full timeline →
Installed prices: design, PE engineering, fabrication, powder coat, delivery and installation. Permit fees and co-op deposits are billed at cost.
| What moves the price | Effect | What moves the price | Effect |
|---|---|---|---|
| LED under every tread + winder | +$1.5–4k | Walnut treads + winders | +$2–4k |
| Winders carried on a masonry wall | quoted | Brushed stainless spines | +40–60% on steel |
| Guards on both sides of flight 1 | +$3–6k glass | Heights over 12′ | +$1–1.5k per tread |
The winders, arms and corner post add about $5–7k over a straight mono stringerconfirm. Full cost breakdown →
| New Jersey · 1–2 family 2024 IRC as amended | Long Island NYS Residential Code | New York City · R-3 2022 NYC Building Code | |
|---|---|---|---|
| Max riser · min tread | 8¼″ · 9″ | 8¼″ · 9″ | 8¼″ · 9″, and 2 risers + 1 tread ≤ 25½″ |
| Max rise of one flight | 12′-7″ | 12′-7″ | 12′-0″ |
| Headroom, incl. over the winders | 6′-8″ | 6′-8″ | 80″ |
| Guard along the flights | 36″ | 36″ | 34″ |
| Guard at the floor opening | 36″ | 36″ | 42″ |
| Winder treads | 9″ on the walking line, 6″ min | 10″ on the walking line, 6″ min | 10″ 12″ from the narrow end, 6″ min |
An open stair joining 3–4 floors of an NYC townhouse may also need sprinklers. Are floating stairs legal in NYC? →
A floating stair is a big decision. Here is what we put in writing.
Standard winder details as a starting point: base, corner post, winder arms, winder geometry and header. We produce PE-stamped shop drawings for your approval.
Still unsure? Send a photo of your stairwell and we'll tell you what fits.
An L-shaped floating stair without a landing. Two straight flights, each on one central steel spine, turn 90° on three tapered winder treads. Both spines and the winders are carried by one slim steel post at the corner.
Yes, inside one- and two-family homes and dwelling units. Each winder must be at least 10″ deep on the walking line, 12″ from the narrow end, and never less than 6″ (NYC BC §1011.5.2 and the NJ residential code). We draw every winder to these numbers.
For a 10′ floor-to-floor height with the winders in the middle, the stair needs about 9′-0″ × 9′-0″ of floor, plus 3′ clear at the bottom step: about 11″ less each way than an L with a landing. Use "Designed around your space" above for your height.
Winders take less floor and you never stop climbing. A landing is easier on the knees, every tread is the same depth and it splits a tall rise into two flights. See L-shaped mono stringer stairs.
Walk on the wide side and they feel like normal steps: on the walking line every winder is about 12″ deep. The narrow ends near the post are steeper, so we keep a continuous handrail on the wall side, where the treads are widest.
Not when it is sized right. Each flight is short, every winder arm is moment-welded to the post and the post takes load straight to the floor. We design for L/480 and 8–10 Hz or more.
From about $34k installed in New Jersey and $40k in New York City for a 9–10′ stair with oak treads and a cable or rod guard. With frameless glass, about $44–57k in NJ and $50–67k in NYC. Final price after we measure.
Floor plans, the floor-to-floor height and photos of where the stair starts and arrives. A rough sketch with dimensions is enough to start.
Your height and turn from above are already filled in. Add a photo of each end of the stair.
