fire door gaps

[nwpattesting]

Hi, I am in the process of arranging for my fire doors to be upgtaded.

The joiner who does a lot of these told me the max 4mm gap is not possible as the door wouldnt close properly with the intumescent strips fitted.

Is that correct ?

Thanks

[AnthonyB]

No, not if fitted properly - this is why a competent fire door contractor should be carrying out these works, I've seen thousands of pounds of wasted work on doors by well meaning joiners.

[nwpattesting]

Thanks for that, Im trying to work out, how thick is the intumescent/ smoke strip ?

does the thickness vary as to whether its a self adhesive one that fits in the frame or a routered one in the door ?

thanks

[Neil ashdown]

There are various types of smoke seal including types that are separate from the intumescent strip.     https://www.lorientuk.com/products/architectural-seals/perimeter-seals 

So the 4mm maximum gap should not be an issue at all and make sure your fire door upgrading contractor has the necessary competence !!

[nwpattesting]

thanks for that ?