Headroom under stairs.

[cdbe]

Can anyone tell me what's likely to be under here, and whether it's likely to be supported by the wall on the left (above the door)?

I'm asking because the door is being moved outward and I'm taking as much as I can out above it. If possible I'd like to gain a bit from below that landing, even if it involves some shallower steel "reinforcement"

It's the main entrance to a large 4 bed house and just feels incredible pokey so I'm happy to put a bit of work in for a small improvement!

View from outside (new entrance porch in progress, outer skin gone) I think timber lintel is just supporting brickwork above and will be replaced by a concrete one higher up..

 

[big-all]

its the undeside off the stair landing it will be stair structure the lath and plaster fixed to it with perhaps a inch to play with
you may get a single tread worth off useful headspace, but the string[stair sides] is still there

 

[cdbe]

Thanks, a single tread would make a big difference. So I could possibly "hollow out" under the landing along the red line but the stringer would be above the door architrave so I wouldn't gain much unless I could deal with that? I think that triangle between my red line and the newel post is fill as well so that could possibly come out.

I know I'll need to open it up to be certain but the wife is on the warpath and I've already used up this month's "dust allowance"

 

[big-all]

without looking you wont know but in the area you have the red line on the change
do you have a landing or winders??
from flat to angle is the height off the first tread from the landing going up if its a landing if not is will go from nothing at the newel to tread wide at the wall

 

[CACKATALLTRADES]

without looking you wont know but in the area you have the red line on the change
do you have a landing or winders??
from flat to angle is the height off the first tread from the landing going up if its a landing if not is will go from nothing at the newel to tread wide at the wall

My sources tell me he has a landing

 

[big-all]

yes i know it looks like a landing but the timber going past the newel looks odd
it actually looks like a very chunky frame under the flight causing the angle to meet 1/4-1/3 way across under the landing ??
but wont know without opening it up

 

[CACKATALLTRADES]

yes i know it looks like a landing but the timber going past the newel looks odd

https://www.diynot.com/diy/threads/toughened-glass.590982

 

[big-all]

ahh ok cheers

 

[cdbe]

This looks very similar to my layout:

Measuring above and below, the landing appears to be a bit over 100mm deep so I presume some small supporting joists, which I might be able to replace with some 1" steel box section. I'll investigate when the wife goes back to work.

 

[Deleted member 174758]

Stop guessing and strip the lath and plaster off beneath that quarter landing(?) - it's the only to see what you have under there. With Victorian builders, who are notorious for not "following the rules" it is often the only way to do this. Tell the missus you can't make an omlette without breaking eggs and offer to cover it up with some PB or a sheet of plastic if the sighty of the underside of the landing offends her

 

[cdbe]

Wife's back at work!

Bit disappointed with the joist depth (75mm) but there was a good thickness of lathe and plaster so I'll gain 60mm by replying joists with 25mm box section. The timber lintel is coming out to be replaced by one a bit higher so I'll hang the box of that. Uncovering the two steps has made a big difference.

I want the two sections of stringer out so I'll have to think about that!

 

[Deleted member 174758]

Bit disappointed with the joist depth (75mm) but there was a good thickness of lathe and plaster so I'll gain 60mm by replying joists with 25mm box section.

Steel? Seems a bit lightweight to me, but with sufficient bracing and a plywood floor it could be enough.

If there were 3 x 2s in there it's more than likely it didn't need any more because the span is so small (3ft or so?)

The timber lintel is coming out to be replaced by one a bit higher so I'll hang the box of that

Presumably you intend to install a steel or concrete lintel instead. And hang your 25mm box section framework off that?

I want the two sections of stringer out so I'll have to think about that!

Seriously? The stringers are the main structural element in any staircase and aren't supposed to be cut into or modified (apart from anything else it is notifiable work). Unless you intend to replace the quarter and upper stairs with fabricated steel with appropriate anchor points into the existing stairs (which requires calcs to satisfy the BCO) I can't see how you will do this legally. It might not make difference now, but it could make a difference when you come to sell

 

[cdbe]

I've exaggerated - I meant remove a section of the stringer - I'm thinking of a flat L shaped plate cut from 12mm steel plate to restore the strength lost by cutting out the triangle.

Whatever it is will be seriously over engineered to more than compensate for what is removed.

 

[cdbe]

Metalwork prepared:

 

[big-all]

just make sure you fully support temporary or permanently before you cut anything