Fastening staircase/stringer? Will this be good?

[eran]

Currently decorating the upper floor of the house and have realized that one can never assume anything when it comes to consistency between blueprints and reality.

The floor plan for the upper floor was taken from the original house manufacturer's design and was slightly modified. I naively thought that the staircase ordered with the house was also made according to the blueprints that came with the house, but unfortunately not. The staircase was delivered based on a different design. The house supplier has gone bankrupt, so that route is closed.

The blueprint we used for the upper floor shows that the staircase is positioned in a space that should be open between two rafters, cc 1200mm. The parts delivered with the staircase require an opening width of 905 mm, so that the banister and handrail will fit.

I have found the stair manufacturer, and they can supply the parts we are missing but do not want to advise on securing the stringer to the intermediate floor. The staircase is already in place.



I want to remove the red-marked and crossed-out studs, but the stringer is currently screwed into the nearest stud (red crossed). Can I instead lift the floorboard and screw the staircase according to the blue arrow? That is, through the cross beam that the stringer is against with, say, 1 - 2 screws 6x120mm?

Another picture from a different angle.



Thank you in advance.

 

[Matti_75]

If you attach a joist under the landing that you attach the stairs to, you can remove the desired joists.

 

[eran]

So, for example, a 45x70 that fits between the vangstycken is screwed onto the plate as support under the top step?

Then I don't need to screw the vangstycke from the back through the crossbeam?

Correctly understood?

 

[Matti_75]

Yes, you screw into both the floor rule and the staircase.

 

[eran]

Case closed!

Opened the floor and drove 2x6x120 wood screws through the beam and into the inner stringer. Became solid and good. Will complement with a beam under the top step when I tidy up around the stairwell.