Loft stairs and landings

[JC_]

Hi all,

I’m designing a loft conversion for my mid terrace Victorian house to create a third bedroom. As it’s a small 2 bed, the main challenge I’m having is getting a compliant staircase in that minimises loss of existing bedroom space, and lands in the right place. I need to leave the main bedroom as intact as possible, but happy to reduce the small bedroom to as shown.

Having considered many different staircase configurations, the layout below is the only one I can see that may have potential.

The issue I am having is the landing at the bottom of the loft stairs. I’m aware that it needs to be the width and depth of the tread width (which I have reluctantly reduced to 600mm wide for this reason). Because of the adjacent door to the small bedroom (which I have reduced to 610mm), it only leaves 425mm between the loft door and bottom stair.

As the loft will be one room only, could there potentially be any flexibility on this requirement? Does anyone have experience with BCOs and how they might view a situation like this?

If I remove the bottom 3 winders to free up space here, I would need to add them at the top which eats into the loft space. Also, I presume that structurally I need to keep the majority of the staircase against the party wall, as there are no other loadbearing walls to support say a double winder half way up, if that makes sense? Or could that be possible?

Putting the door at the top of the stairs would be far from ideal due to limited loft floor area and head height (planners here will only consider a small dormer).

Any advice would be really appreciated!

Proposed First Floor:

Proposed Loft Space:

 

[freddiemercurystwin]

What's the proposed floor to floor height after you've allowed for the new loft floor etc?

 

[JC_]

2715mm floor to floor. Risers 209mm, treads 233mm.

 

[freddiemercurystwin]

Have you got quite tall ceilings then?

 

[JC_]

Have you got quite tall ceilings then?

Fairly tall I suppose, 2450mm.

EDIT: Having looked in more detail at the door at loft level option, it might actually be a better way forward. It frees up the first floor hall and does away with my main problem. Can get a 686mm door to existing small bedroom, and can also increase staircase width to 650mm which I’m more comfortable with.

There is also then space to add one tread at the bottom before first turn, so can remove one from the top.

Space at the top for 650x650 landing with door opening into loft room. Actually doesn’t take away too much from the loft space, on paper anyway.

Would be interested to hear your thoughts.

 

[^woody^]

There won't be any flexibility if there are other options. There is no reason that the fire door can't be at the top of the fight other than that you don't want it there.

 

[JC_]

There won't be any flexibility if there are other options. There is no reason that the fire door can't be at the top of the fight other than that you don't want it there.

Thanks, that makes sense. Since my original message I have played around with the layout and the fire door at the top of the stairs should be do-able I think:

 

[freddiemercurystwin]

Yes I had a look at a few alternatives for the stair, but no other options really, squeezing the stair in to small houses is always an issue with a compromise somewhere. BTW you should be able to get your new floor depth down a bit with a decent SE. Can you not lose that riser from the top and get it at the bottom? I don't know if you have or not but if not it would be worth playing with some of the online stair planners as they give you actual finished sizes rather than theoretical 600 wide stairs.

 

[JC_]

Yes I had a look at a few alternatives for the stair, but no other options really, squeezing the stair in to small houses is always an issue with a compromise somewhere. BTW you should be able to get your new floor depth down a bit with a decent SE. Can you not lose that riser from the top and get it at the bottom? I don't know if you have or not but if not it would be worth playing with some of the online stair planners as they give you actual finished sizes rather than theoretical 600 wide stairs.

Thanks, that’s really helpful and good to know I’m on the right track with this!

For the floor depth, for now I’m allowing 200mm deep joists to be hung as low as possible between existing 100mm ceiling joists (hung from RSJs spanning between party walls), plus 18mm for floor boarding. Would be great if SE could perhaps reduce this a bit.

I thought about putting the riser from the top at the bottom instead, but it would be a squeeze - there is only 209mm space between the bedroom door lining and the bottom step. Not sure if there is anything in the regs that says you can’t have a staircase finish right at a door opening, as long as the door isn’t opening towards the stairs? I have currently allowed for an 686mm wide door here which is what’s there already, but I guess I could reduce to a 610mm as it’s just a small box room, but not sure if it would be uncomfortably narrow, or if BCO would like it.

Also, for 2 metre head room I would need to pull back the loft floor above back by around 200mm to allow the additional rise here.

With the last rise at the top as I have shown, could there be issues with supporting the outer joist, i.e. the inside corner of the L shape cut out? Existing wall below seems to be stud, but it is brick to first floor joist level.

Yes, I’ve been in touch with TK Stairs and have used their online planner for previous iterations, but will look at it in more detail for this configuration.

 

[Terrywookfit]

Have a play on Stairbox web site

 

[^woody^]

See if an alternate tread flight would be acceptable.

 

[JC_]

See if an alternate tread flight would be acceptable.

Thanks for the suggestion, but I won’t be going down that road.

 

[freddiemercurystwin]

With the last rise at the top as I have shown, could there be issues with supporting the outer joist, i.e. the inside corner of the L shape cut out? Existing wall below seems to be stud, but it is brick to first floor joist level.

Well that will be for your SE to determine but typically a beam spanning between your steels made up of 2 or 3 joists bolted together will suffice.

 

[JC_]

Well that will be for your SE to determine but typically a beam spanning between your steels made up of 2 or 3 joists bolted together will suffice.

I didn’t think of that, thanks. Sounds like it should be possible then.

I’ll appoint a SE once I have planning permission, but intend to submit it for planning myself before spending money on consultants in case the planners decide it’s a non-starter. That’s why I’m trying to make sure it’s all feasible at this stage.