Staircase opening, how large

[Lindgrenski]

You can adjust the staircase a bit so that the floor joist is above the second step. The stair width (or whatever you want to call it) is 168cm, so it's less than 40 cm that needs to extend beyond the floor joist opening.
The basement is being excavated and the ceiling height will be 230-240cm. I'll just have to measure the height of steps 2 and 3, simply, if I find them in the pile of boards. :blushing:

 

[Mikael_L]

...The clearance here probably needs to be a few decimeters higher than an average-height person to avoid feeling the need to bend back when walking down the stairs...

The minimum allowed clearance according to BBR is 2 meters. To avoid claustrophobic feelings, one or two additional decimeters can be added.

http://www.boverket.se/Global/Bygga...tt_8/BBR_avsnitt8_sakerhet_vid_anvandning.pdf
8:34

also see (pages 39-46):
http://www.ltu.se/polopoly_fs/1.15491!sp rapport 2008_45 harmonisering.pdf

For tips on maximum compression, a study visit to a submarine, preferably a WW2 model, is recommended.

 

[Lindgrenski]

The minimum allowable clearance according to BBR is 2 meters.

Yes, but I'm not interested in BBR now, just whether it works.

 

[Mikael_L]

Do not expect to have more than the first step under the roof, then there must be a stairwell over the head.

immobil, do you have a program that designs stairs?

 

[Mikael_L]

Well, I'm not interested in BBR but if it works.

I believe that BBR doesn't work, they have too strict rules. 2.2 meters in free height works.

 

[Mikael_L]

You can gain an additional step by chamfering the opening in the stairwell, if it works constructively that is.

Say the stairwell starts 25cm further into the ceiling, and then slopes about 30-35 degrees. Then the floor above can cover a bit more area above the stairs. But it becomes trickier with the joists, more work. And in some cases impossible.