Temporary/Permanent stair support for insulation & UFH

[robinbanks]

40mm screed

I'm still not sure why you'd want to remove the screed?

think a block of wood is much weaker than a post

Not in a "force along the grain" direction. Along the grain, a block of wood is a post

It's something of a nonsense to assert that a wooden support is incapable of adequately supporting a wooden staircase because the support is made of wood

I don't think adding a block is quite the same

I do wonder about what you think some times, but oftentimes it seems to be a healthy wedge of unlikely whataboutery

A couple of mm of sinkage could mean a lifetime of squawking!

Sounds like you're asserting that a staircase arrives from factory perfectly square and if installed such that it will drop by 2mm when installed, it will squeak when walked on forever. It will just twist the 2mm, come to rest and function as you expect. Wood doesn't shrink at anything like the rate you purport

hold it down as well as up

Yes they do tend to float away if you don't bolt them down, don't they?
It's why I say stairs aren't to be trusted; they're always up to something

 

[noseall]

I'm still not sure why you'd want to remove the screed

Highly unlikely. There are practical reasons for using a post support too (adjustment), so not such a silly idea.

 

[Ivor Windybottom]

Sigh. The good old internet.

Anything freestanding can flex and wriggle about. That's why you get those annoying squawks from so many staircases. While the access is there, attach it rather than leaving it free to move.

 

[robinbanks]

Highly unlikely. There are practical reasons for using a post support too (adjustment), so not such a silly idea.

But you said you wanted to remove the screed. Now you're saying you don't want to remove the screed?

If you're insistent that the screed won't support it (..it will), cut a piece of wood the length required and support the case with it.

More than adequate structurally, better thermally and every bit as adjustable because you aren't going smash out the screed to get to the fixing that readjust the adjustable post any more than you're going to smash out the screed and replace the wood support with another to resolve a 0.1% shrinkage

Anything freestanding can flex and wriggle about. That's why you get those annoying squawks from so many staircases. While the access is there, attach it rather than leaving it free to move.

Fixing the case in the location you propose, with the fixing you propose, will not stop a mid flight step from developing a flex that causes a squeak

 

[noseall]

But you said you wanted to remove the screed. Now you're saying you don't want to remove the screed?

Nonsense.

If you're insistent that the screed won't support it (..it will), cut a piece of wood the length required and support the case with it.

More than adequate structurally, better thermally and every bit as adjustable

Not at all really. But adequate.

 

[robinbanks]

Come on nosey, you've posted enough pictures to prove you know how to adjust the length of a piece of wood. I can't believe they're all someone else's work

You could even do it with a cut-off saw