DIY Doctor UK DIY Forums

Hi all, my house has a loft conversion fitted by the previous owners. The loft rooms are fitted with fire doors. As I have been renovating downstairs I have fitted fire doors where required. I am now doing the first floor, where oddly ‘normal’ doors were fitted. The walls are only single block, so about 80mm deep. As fire doors are 44mm, are 80mm liners sufficient (if I replace with 32mm thick timber), or do I need to fit deeper liners and somehow frame out around the protruding liner, under the architrave? Thanks in advance.

Hi lozza99,
The 80mm wide linings should be ok but you will need to fit intumescent strips and possibly a fire/smoke threshold.
Regards S

Hi Stoneyboy, thanks for the response. Yes the other (more standard sized) liners I’ve fitted have grooves for intumescent strips, and I would do the same with a custom liner if I had to make one. Interestingly looking up info re smoke/fire thresholds it’s not clear if they are required or not. I’d rather not fit them as I don’t like road bumps in the floor. I guess an alternative would be to fit an intumescent strip to the bottom edge of the door? Still a bit concerned that the stops will be fairly lightweight, but I guess that single block walls are not uncommon. It would be nice if the regs were clear!

Hi lozza99,
Sounds like you have a fair idea of how to do things. If you are concerned about the stops why not make your own linings out of 89x38 CLS and machine your own rebates and intumescent strip grooves.
Your proposal to fit intumescent strips on the bottom of the door should be adequate but if your doors are forming a fire protected escape route from the 2nd storey all fire doors must have door closers which shut the doors.
Regards S

Hi Stoneyboy,

Thanks. Yes, based on this I’ll make up my own liners. I’ve just done a custom one (for a walk in cupboard so not a fire door) for a narrow opening.
Re closers, my understanding is that the are only required for doors from house to attached garages? Cheers. L

Hi lozza99,
It will be interesting to see, if you go for some sort of local authority approval, whether they agree with your interpretation of the regulations.
Please keep us posted.
Regards S