Replacing Lipping on FD30 flat entrance doors

[richardinnorwich]

Hi again all,

back to the hive mind for advice and guidance. We've got a couple of notional/nominal FD30 (soon to be FD30S with the addition of intumescent smoke seals) flat entrance doors that need re-lipping as they've been planed below 6mm in the past. We're looking to trim them down and add 8mm hardwood lipping before rebating to take the 15x4mm intumescent smoke seals. My question is a three parter;

1.  I'm assuming that the 6mm minimum is for the lipping itself and you can rebate the intumescent strips into that without having to allow and extra 4mm for the rebate (i.e. making the minimum 10mm in this case)?

2. I'm getting differing info on what glue you have to use; Urea Formaldehyde, Polyurethane and PVA are mentioned as OK by a couple of manufacturers for FD30, only noting that PVA can't be used for FD60 so not sure which one to go for to be on the safe side, might also need to be able to show a data sheet for compliance?

3. For any of the glues recommended for question 2, where can I get them, in a reasonable quantity? The only ones I've come across for the Urea ones are factory production sizes at a couple of hundred quid a time and we're probably only gong to need it for a few doors?

Thanks in advance, Richard

[Neil Ashdown MAFDI]

Based on much-reading of the differing data for many different types of timber fire door construction, I would opine as follows:

1) Best practice is 6mm min thick lipping after planing-in. So 2mm residual thickness behind the intumescent seal when grooved into the door leaf edge. I have come across assessment reports permitting less than 6mm but I feel that shouldn't be relied on generally.

2) Urea Formaldehyde based adhesive is suitable for adhering hardwood lipping to timber-based FD30 & FD60 doors.

3) Cascamite is widely available from online outlets.

PS. Check thickness of door stiles before trimming. There may be no point trimming them down just to fit thicker lipping, if they are already narrow?

[richardinnorwich]

Thanks Neil, some great guidance (as usual). I'd spent a couple of hours searching for the Urea glue with no joy and your recommendation took me to what I needed in one click.

I was really interested  to see your comment regarding stiles thickness, we've got one door that's only got a couple of mm hardwood lipping left so we can see the softwood stile in the rebate for the intumescent strips. Our carpenter was talking about maybe using a 12mm thick lipping to give us a bit more of a safety margin but now I'm concerned that's going to take away too much of the softwood stile, is it something that's an issue or is it OK to do?

I'm also looking for some advice on training too, as a director for the freehold residents management company is there any kind of course/ certification around for that role or the 'responsible person' role. I'm probably not looking for fire door inspection certification level but it would be nice to have something to show that I know the current standards & regulations.

Thanks again, Richard

[Neil Ashdown MAFDI]

Hi Richard,

This is a common problem, installers don't always realise that fire doors have strict trim allowances. If the door has already been trimmed to its max, there's little point in trimming it further just to add timber back again. 

If you can find a certification label on the door, that enables you to contact the door manufacturer for specific advice. 

We provide various types of fire door related training but not specifically Responsible Person training for fire safety generally. https://www.firedoorscomplete.com/