Loft Extension - stairs in middle of house

[canadianinlondon]

Hi MN! Has anyone done a loft extension where the stairs are in the middle of the house? We currently have an escape ladder up to a fairly roomy loft (but it's a triangle shape); we would want to make one side a dormer (facing the garden) to make it roomier. I suspect we'll have to take out some space from the 2nd bedroom to allow stairs to go up to the loft. Attaching floorplan. Would love to hear others' experiences and what they did for this extension. I see loft costs are around 50K£, is it still the same amount with this layout?

Also keen to hear if anyone has other ideas on how to make an extra bedroom/bathroom with this layout :) We do have a side garage we could potentially build on top of but we thought the loft was more straight forward. Also considered a rear side extension for open kitchen/diner but not a top priority for us as we'll rather have an extra bedroom/bathroom at this point.

Door into bedroom t2 where the existing up stair is, then turn at 90 degrees ASAP over the existing stairwell. This minimises loss of floor space in B2 and the cupboards from the other side of the room could be rebuilt under/around the new stair, so virtually no net loss of space in b2?

As in, new door onto new stair, not a new bedroom door!

Agree. If there's the height, have lift stairs using a bit of bed 2 and above existing stairs. Above existing will always lose you the minimum floor space, but you do need to make sure there's height above the current stairs.

We had similar layout (existing stairs through middle though) and had loft stairs next to them where your wardrobes in bed 2 are. But under the new stairs we didn't box in - left them as an alcove in bed 2 so a single bed still fitted under the new stairs.

Without seeing any photos, but assume you have a gable roof with gable ends to the front and rear? If so, bear in mind the regulated headroom you require for the new stair. With the highest point being the middle, the stair would need to start on the side wall and pitch up towards the middle as opposed to starting from the Landing and pitching up towards the side. That is of course unless you’re considering a dormer on the side roof plane to provide the headroom?

Your existing open plan layout at ground floor would cause some issues as you’d normally require a protected staircase. Assuming you would not want to provide some closed off spaces at ground floor, your only other options would be to provide an alternative means of escape at first floor level along with the relevant fire enclosure or a domestic sprinkler system.

Note all existing doors onto the stair including glazing would need to be made fire resisting.