Winder stairs design

[Wayne Whitney]

Hello,

I'm trying to design a code-compliant (UBC 1997) U-shaped staircase for a fairly tight space, so I thought I would look at winder staircases. What I've found is that the 6-inch minimum tread width at the short end basically means that for a 90 degree turn, code-compliant winders don't really save any space over just using a landing. Is this what other people have found, or am I missing something? A table of my calculations is below.

BTW, how does one make stringers for a winder staircase?

Thanks, Wayne

Footprint for effecting a 90-degree turn

10" tread depth (measured 12" in on the winders) 6" minimum winder short edge Offsets measured from inside corners of steps above and below turn

Steps With Landing Winders

1 (0,0) N/A 2 (10,0) (6,6) 3 (10,10) (10.25,10.25) 4 (20,10) (14.2,14.2) 5 (20,20) (18.1,18.1)

For 4 steps and below, the 6" short edge determines winder size For 5 steps and above, the 10" tread depth determines winder size

[HerHusband]

Wayne,

The easiest method is to build a series of platforms stacked on top of each other. You'll need to rip the boards to the width you need for the riser height, but otherwise they're just simple boxes.

Then make the straight runs with conventional stair stringers.

I'm not a big fan of winder stairs, the few I have used just don't "feel" safe, especially if you are carrying an armload of stuff down the stairs.

Other than dividing the landing in half for an extra step up, I would stick with conventional stairs. Just my personal preference.

Fine Homebuilding had a nice article on "L-Shaped Stairs" several years ago (1997?) that discussed building winder stairs.

Good luck,

Anthony

[Wayne Whitney]

So it's sort of like "Tower of Hanoi", the first winder step is a box which covers the entire footprint of all the winders, the second winder step is a box which is smaller by exactly the size of the first winder step, and so on?

Thanks, Wayne

[HerHusband]

Wayne,

Correct. You would build the first platform, just like you were framing a landing. Then build your first box on top of that, so that it forms the next smaller platform, then another on top of that one, till you can revert back to straight stair stringers.

Depending on how much width you have available, you may be able to frame the stairs so that you have a straight run up to a landing, turn 90 degrees, have another step or two, then step up to a second landing, turn

90 degrees again, and the final straight run up to the second floor.

You may have a number of options depending on the space available.

I will need to build some stairs to access a garage attic soon, so I'm in a similar situation as you. My stairs will be "L" shaped, but I'm hoping to avoid a winder if at all possible.

Take care,

Anthony