uCAD

Stairs by floor height · 10 ft 9 in · U-shaped, winders

U-shaped stairs with winders for a 10 ft 9 in floor height

19 risers of 6 13/16″ and 18 treads 11 7/16″ deep, at 31°. 36″ wide, it takes 6′ 3 7/8″ × 8′ 8 1/2″ 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

19risers
6 13/16″each riser
11 7/16″going (tread depth)
18treads (the last riser is up to the floor)
31°pitch
6′ 3 7/8″ × 8′ 8 1/2″footprint, over the treads
123456789101112131415161718up6′ 3 7/8″8′ 8 1/2″
The plan: steps numbered from the bottom, the walking line in blue.

More or fewer steps

10 ft 9 in (129″) can be climbed in fewer, higher steps or more, lower ones. Each opens in uCAD as this stair with that many risers.

RisersEach riserGoingPitchRun of a straight flightHow it walksIn uCAD
177 9/16″9 13/16″38°13′ 1 1/2″treads under the IRC’s 10″open
187 3/16″10 5/8″34°15′ 11/16″comfortableopen
196 13/16″11 7/16″31°17′ 1 1/2″comfortable (drawn here)open
206 7/16″11 13/16″29°18′ 8 7/16″comfortableopen

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. 260 parts in all, every bolt and weld among them. Sizes in inches, length × width × thickness.

PartQtyLengthWidthThickness
stringer (shaped)1123 11/16″15 7/8″1 15/16″
stringer (shaped)1122 3/16″15 7/8″1 15/16″
stringer (shaped)180 15/16″13 5/8″1 15/16″
tread (shaped)143 5/16″21 9/16″1 9/16″
tread (shaped)148 3/4″19 1/8″1 9/16″
tread (shaped)142 3/4″21 11/16″1 9/16″
tread (shaped)143 11/16″21 1/4″1 9/16″
tread (shaped)143 1/8″21 3/8″1 9/16″
tread (shaped)148 11/16″18 11/16″1 9/16″
stringer (shaped)179 1/2″10 3/8″1 15/16″
stringer (shaped)178 15/16″10 3/8″1 15/16″
tread1237 3/16″12 3/8″1 9/16″
post, timber 90x901127 3/16″3 9/16″3 9/16″
post, timber 90x90185 1/16″3 9/16″3 9/16″
post, timber 90x90182 11/16″3 9/16″3 9/16″
post, timber 90x90166 15/16″3 9/16″3 9/16″
post, timber 90x90153 3/4″3 9/16″3 9/16″
post, timber 90x90146 5/8″3 9/16″3 9/16″
handrail, round 50 mm (shaped)275 1/8″1 15/16″1 15/16″
baluster, steel square bar 18 mm (shaped)2433 5/16″11/16″11/16″

Fixings: 24 × stud M8x80, glued, 24 × 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

U-shaped stairs with winders for 10 ft 9 in in 3D, between its floor and the floor above
This stair in 3D, between its floor and the floor above.

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 10 ft 9 in in a 7 × 10 ft stairwell”, and it draws one that fits.

Open this stair in uCAD

Same height: Straight · L-shaped, landing · L-shaped, winders · U-shaped, landing · Spiral · Square spiral
This stair for 10 ft 6 in · 11 ft · all heights