Fire door stop - issue with building control

[KnightWhoSaysNi]

My loft conversion is finished and I've just had the final building control inspection.

A few days ago a different team of builders (not the loft guys) started doing some other work, which involves dividing the large through lounge into two smaller rooms, each with its own door. The partition wall is up and they've fitted fire doors and fire door frames in both rooms.

The door stops on these two doors look different to the ones in the other rooms - well the only difference I can see is they're narrower.
The stops come from the original fire door frame / lining pack, so they're presumably fire rated (wouldn't make sense otherwise). The stops don't have FD30 labels on them, but the lining sets do.

The inspector said these stops are not fire rated and has asked me to replace them with FD30 ones. At the time he said it I believed him, but after he left I checked with the builder and he said they came from the original fire door lining packs.

Now I'm wonderinbg what to tell the inspector to convince him? Is there a surefire (no pun intended) way to tell if a door stop is fire rated or not? Like a certain thickness? Or maybe a label somewhere inside?

 

[JohnD]

I have two types in my house.

The older ones have the large wooden batten as a doorstop. The newer linings have a narrower batten, and a groove where an intumescent strip is fitted (mine have the type which incorporates a furry smoke strip, which I like because it also blocks draughts and noise).

When I enquired, I understood that you could choose between big batten and no strip; or narrow batten and intumescent strip. The strips are not expensive. They are self-adhesive into the groove. They go all round the door but not at the bottom. There are several widths. Mine came from IronmongeryDirect.

Ask him if intumescent strip will meet the requirement. The narrower battens look neater.

 

[KnightWhoSaysNi]

Cheers. I've googled the product in question and found a CERTIFIRE document which specifies the door stop's dimensions (only 14.5mm wide) and says it's fire approved. I'll send him the link and hope this is convincing enough.

 

[Nakajo]

Set fire to the room and time how long the door lasts. Seriously, there's something like a 15mm minimum for stops, isn't there? - I seem to remember thinking it was surprisingly small.

 

[KnightWhoSaysNi]

The inspector has confirmed what JohnD said: I need intumescent strips with these narrow battens.

 

[Nakajo]

Actually, I think door stops are supposed to a minimum of 12mm x 25mm (w x d), but we generally specify a minimum of 22 x 25

 

[freddiemercurystwin]

AFAIK the thickness of the stop of and FD30 is now determined by the door manufacturer as they tested the door, not a generic dimension from a BS or other standard as it used to be.

 

[Nakajo]

But fire doors for private residential use don't have to be 'off-the-shelf', do they?

 

[freddiemercurystwin]

But fire doors for private residential use don't have to be 'off-the-shelf', do they?

A fire door design is tested and it is tested with a particular door stop. I don't really understand your point?

 

[chappers]

AFAIK the thickness of the stop of and FD30 is now determined by the door manufacturer as they tested the door, not a generic dimension from a BS or other standard as it used to be.

That was my understanding, if a manufacturer, has a specification that is certified to comply with the relevant condition, then that specification takes precedent over the relevant accepted design in the regs.

 

[jeds]

As chappers and freddy above. FD30 doors aren't specified by BCOs, they are tested and specified by door manufacturers. The test certificate will say something along the lines; this door is an FD30 door when used with x, y, z door stops, frames, etc. The most common door stop spec (for fire testing purposes) is 12mm but that's not to say a manufacturer hasn't tested a door with 25mm stops.