U-Shaped staircase: is it allowed to have a step in the middle section like in the figure?

spupazza

Hi, I wanted to ask

if a step in the middle like in the picture below would be allowed.

On the building regulation I can't find anything that would explicitly disallow it.

sydthebeat

Yes it's allowed. Any level landing must be at least the same width as the stairs itself, which you have in that pic

Mellor

https://www.boards.ie/discussion/2058331339/u-shaped-staircase-is-it-allowed-to-have-a-step-in-the-middle-section-like-in-the-figure

Look under Length of Flights 1.1.11

"A flight containing one or two risers in private stairs should be situated at the bottom of the stairs."

at the very least, I'd try and design out a single step. If necessary 2 would be better that 1. In the image you posted. That could have been two.

https://www.boards.ie/discussion/comment/121617352#Comment_121617352

I think it's borderline tbh. Seems a little subjective, based on how somebody interprets the above.

Certainly wouldn't be happy with a single step in a public/semi-public stair. But in a private stair, you are leaning on people being "very familiar with the stairs". Nonetheless, 1.1.11 is a bit of a sticking point.

sydthebeat

^

fair point of interpretation.

spupazza

If I understand correctly the regulations, the landing needs to be at least as deep as the width of the stairs, which should mean that if my staircase has a clear width of 80cm (which I believe is the minimum allowed) then I can have the half landing measuring 160cm x 80cm. Would that be correct?

I'm looking for the smallest allowed footprint for u-shaped staircase with steps with 220mm going and 245mm threads, 50mm on each side for railing.

Mellor

https://www.boards.ie/discussion/comment/121652953#Comment_121652953

800 is minimum clearance, not width. Assuming there are no accessibility requirements.

Assume you mean 220 rise, which is the limit. 245 going will also put the pitch and gait both at the limit, which I imagine you know.

If any sides are enclosed by a wall, you’ll need to allow another 50 gap behind the handrail. If open, then just 50 for the balustrade.

Why do you need a minimum footprint? I generally dislike stairs close to these limits, they are very uncomfortable

spupazza

https://www.boards.ie/discussion/comment/121656762#Comment_121656762

Thanks for your detailed reply.

I'm exploring options for minimizing the footprint to avoid increasing the overall size of the house and, consequently, keeping costs down.

While I appreciate the idea of having larger stairs, my current plan includes incorporating two identical staircases—one leading to the first floor and the other to the attic.

While I haven't made any definitive decisions yet, I am actively seeking to determine the smallest viable size. Opting for larger staircases could potentially add around 4-5 square meters to the house, which, even at a low cost of 2k per square meter, may translate to an additional 8-10k (with large approx) to the overall cost of the house

Mellor

I understand the concern with costs. And you are right that it’s more than the cost of the stair, it’s roof, the floor, extra walls. but 3 extra steps for a 175 rise would only be 1sqm at most. 100mm on the width would be <400mm2.

Everything has a cost. But cost benefit there is definitely worth it. If you want to shave 1-2sqm off the whole house. Take it off a bigger room, ideally a corridor. Not the stair.