Stairs by floor height · 9 ft · U-shaped, winders
U-shaped stairs with winders for a 9 ft floor height
16 risers of 6 3/4″ and 15 treads 11 7/16″ deep, at 31°. 36″ wide, it takes 6′ 3 7/8″ × 7′ 9 1/16″ of floor. Six winders carry it round the half turn, each taking a riser, so it needs no landing.
Open this stair in uCADWhat it’s made of
More or fewer steps
9 ft (108″) can be climbed in fewer, higher steps or more, lower ones. Each opens in uCAD as this stair with that many risers.
| Risers | Each riser | Going | Pitch | Run of a straight flight | How it walks | In uCAD |
|---|---|---|---|---|---|---|
| 14 | 7 11/16″ | 9 13/16″ | 38° | 10′ 7 15/16″ | treads under the IRC’s 10″ | open |
| 15 | 7 3/16″ | 10 1/4″ | 35° | 11′ 11 5/16″ | comfortable | open |
| 16 | 6 3/4″ | 11 7/16″ | 31° | 14′ 3 1/4″ | comfortable (drawn here) | open |
| 17 | 6 3/8″ | 12 3/16″ | 27° | 16′ 3 1/4″ | comfortable | open |
The IRC (US homes) allows risers up to 7¾″ and asks for treads of at least 10″, 6′8″ of headroom and a width of 36″; states and towns amend it. Check the code that applies to yours.
What it’s made of
Drawn as it’s built, in timber with open treads: treads housed in the stringers, posts under the turns, a railing on its newels. 236 parts in all, every bolt and weld among them. Sizes in inches, length × width × thickness.
| Part | Qty | Length | Width | Thickness |
|---|---|---|---|---|
| stringer (shaped) | 1 | 109 7/8″ | 15 5/8″ | 1 15/16″ |
| stringer (shaped) | 1 | 94 13/16″ | 15 3/8″ | 1 15/16″ |
| stringer (shaped) | 1 | 80 7/8″ | 13 9/16″ | 1 15/16″ |
| tread (shaped) | 1 | 43 5/16″ | 21 9/16″ | 1 9/16″ |
| tread (shaped) | 1 | 48 3/4″ | 19 1/8″ | 1 9/16″ |
| tread (shaped) | 1 | 42 3/4″ | 21 11/16″ | 1 9/16″ |
| tread (shaped) | 1 | 43 11/16″ | 21 1/4″ | 1 9/16″ |
| tread (shaped) | 1 | 43 1/8″ | 21 3/8″ | 1 9/16″ |
| tread (shaped) | 1 | 48 11/16″ | 18 11/16″ | 1 9/16″ |
| stringer (shaped) | 1 | 66 1/16″ | 10 3/8″ | 1 15/16″ |
| stringer (shaped) | 1 | 52 1/4″ | 10 3/8″ | 1 15/16″ |
| tread | 9 | 37 3/16″ | 12 3/8″ | 1 9/16″ |
| post, timber 90x90 | 1 | 113 1/8″ | 3 9/16″ | 3 9/16″ |
| post, timber 90x90 | 1 | 71 1/4″ | 3 9/16″ | 3 9/16″ |
| post, timber 90x90 | 1 | 68 11/16″ | 3 9/16″ | 3 9/16″ |
| post, timber 90x90 | 1 | 53 3/4″ | 3 9/16″ | 3 9/16″ |
| post, timber 90x90 | 1 | 52 1/8″ | 3 9/16″ | 3 9/16″ |
| post, timber 90x90 | 1 | 46 9/16″ | 3 9/16″ | 3 9/16″ |
| handrail, round 50 mm (shaped) | 1 | 61 3/4″ | 1 15/16″ | 1 15/16″ |
| handrail, round 50 mm (shaped) | 1 | 48 1/2″ | 1 15/16″ | 1 15/16″ |
| baluster, steel square bar 18 mm (shaped) | 17 | 33 5/16″ | 11/16″ | 11/16″ |
Fixings: 17 × stud M8x80, glued, 17 × screw 5x45, 5 × bracket, concealed post base 90, 12 × anchor bolt M10x100, 54 × washer M10, 38 × nut M10, 10 × stud M10x117, 2 × anchor bolt M10x200, 2 × bracket, steel angle 100x100x8, 2 × stud M10x85, 16 × bolt M10x170, 16 × nut M10, barrel.
Closed risers, a steel frame, another width or railing: change it in uCAD, and the parts are worked out again, with a cut list of the boards to buy. Sizes of the structure are the library’s defaults for a house stair, not an engineer’s calculation for yours.
Another height or width
Will it fit your room?
Open it in uCAD, draw your walls round it and look: turn it the other way, move the turn up or down, change the width. Or tell the AI: “a stair for 9 ft in a 7 × 10 ft stairwell”, and it draws one that fits.
Same height: Straight · L-shaped, landing · L-shaped, winders · U-shaped, landing · Spiral · Square spiral
This stair for 8 ft 9 in · 9 ft 3 in · all heights