Plasterboard under stairs - building regs?

[mazdaq]

Had a new stairway put in and we're going to use the void underneath as a cupboard. But do I need to plasterboard the underside of the stairs inside the cupboard to meet building regs?

I had a feeling it was a requirement but having googled it, can't find an answer.

 

[KenGMac]

mazdaq, good evening.

is the Staircase completely "New" or? is it a replacement?

Is the stair enclosed, meaning are there walls on each side of the stair as it rises from one floor to the floor above / below?

Sorry no immediate answer, just some clarification needed please.

Ken

 

[bobasd]

tack up two layers of 1/2" plasterboard, stagger the joins if any and you will have half an hours fire resistence. but it all depends on the kind of stairs installed.

 

[mazdaq]

mazdaq, good evening.

is the Staircase completely "New" or? is it a replacement?

Is the stair enclosed, meaning are there walls on each side of the stair as it rises from one floor to the floor above / below?

Sorry no immediate answer, just some clarification needed please.

Ken

Hi Ken

Thanks for the reply. Yes it is completely new - part of a new extension and the stairs go from the basement up to the ground floor.

The staircase double backs on itself so it goes up half a flight, then half landing to turn 180 and then up the the second half. There is always a wall on the left hand side (as you go up) but not on the right.

Thanks

 

[mazdaq]

KenGMac just wondering if you had any thoughts on this? Thanks

 

[KenGMac]

mazdaq, good evening again.

If it were me, I would fix two layers of 15.mm. Plasterboard to the underside of the entire stair case, including the half landing, why because in the event of a fire in the basement the stairs underside [which I have presumed to be timber?] will give more time to effect an escape.

If you fix say 50.mm x 50.mm battens to the stingers [the sides of the Staircase] either as a straight run of timber, or cut the timbers between the treads [more of a pain than the latter??] then fix the two layers of plasterboard to the 50.mm X 50.mm battens.

As bobasd, above stagger the joints as far as possible to assist in prevention of spread of fire.

If you consider it, given Grenfell any positive fire suppression / prevention is to be adopted ? In your case a few ££ may save your life? by giving that few extra seconds to escape.

Hope this assists?

Ken

 

[mazdaq]

Yes that does help very much, thanks Ken.

Good advice and makes sense.

 

[John D v2.0]

building control will have any requirements for fire doors and compartmentalisation. normally the stairs wouldn't have any particular requirement unless it's an escape staircase for upper floors. Do you have a fire door at the bottom or top of the stairs anyway?

 

[mazdaq]

building control will have any requirements for fire doors and compartmentalisation. normally the stairs wouldn't have any particular requirement unless it's an escape staircase for upper floors. Do you have a fire door at the bottom or top of the stairs anyway?

Hi John
Thanks for your reply. Yes there is a firedoor at the bottom of the stairs. That's what I was wondering whether building control had any regulations regarding the staircase. I couldn't find any mention of it on my building reg plans and I'm waiting for building control to get back to me on it. Having googled it, I can't find any mention of it.
Thanks
Chris

 

[John D v2.0]

Fair enough in that case the stairs or cuipboard wall would also be a fire compartment wall, so as what the other posters already mentioned you would need double board or single 15mm pink board, skimmed

 

[mazdaq]

So it needs to be skimmed as well to meet building regs?

 

[John D v2.0]

That was specified in ours by the structural engineer, although he was talking about the protection to the steel beams. Maybe staggered joints would be enough, someone else would comment. You certainly would need to make sure no gaps or weak points