Jump to content

Intumescent strips jamming the door.


Recommended Posts


I'm fitting fire doors in a house I'm converting to an HMO. The frames are new and have been routed (by the supplier) for combined smoke/heat strips. I'm a plumber by trade but have hung a few doors before but need some advice on these please.

I fitted the frame and got everything looking fine and hung the first door with an equal gap of no more than 3mm around the edge. However when I fitted the strips the door wouldn't close easily because of the smoke brush being too proud. To enable it to close smoothly to meet the regs I'd have to plane the door back by 2-3mm. Not only is this going to look very unsightly (a gap of 5-6mm) it then actually exceeds the regulation 3mm gap. Is it possible that the timber supplier didn't rout deep enough for the strip and if so should I just run through it with my router again? The plastic part of the body of the strip stands proud of the frame by about 1mm. If I routed deeper say to make the strip recessed by about 1mm it would solve the problem or is this not recommended.

Any advice?

Link to comment
Share on other sites

  • 2 weeks later...
Guest LisaVen

Hi we have brush smoke seal sin one of our care homes, the residents need hourly checks and are complaining of the noise of the seals when the door is opened and closed. All doors have a 3mm gap around and have recently been renewed, can we cut a shallow groves into the doors to inset the seals to reduce the noise? is there a maximum gap between the door and frame.

Link to comment
Share on other sites

The gap around the door, (two sides and head of door) should be 3 mm, however if the door is a FD30s then that gap needs to be sealed by a cold smoke seal to prevent cold smoke from percolating through that gap in the early stages of a fire. If you sink the cold smoke seal into a grove and it doesn't contact with the frame then its purpose will be lost. Have you tried other types of seal which may prove more silent than the ones fitted now.

Link to comment
Share on other sites

  • 8 months later...
Guest Guest

Hi there Lisa

Did you ever manage to resolve the noisy opening issue.

We have a 3 storey new build house and the strips are noisy so considering replacing them with a different make perhaps?

Tom what different type of seals would you recommend to try?

Link to comment
Share on other sites

  • 1 year later...
  • 4 weeks later...

There are two types of seal on fire doors, on door installed after 1987 there is always an intumescent seal, fixed in a groove, which expands when heat is applied to it and fills in the gap between the door leaf and the frame, preventing the fire to pass. Also on some doors a cold smoke seal is fitted, which seals the gap between the door leaf and the frame, which prevent cold smoke from passing through the gap before heat activates the intumescent seal and you can get combination seals both intumescent/cold smoke seals.

There is gap between the intumescent seal and the frame which will not cause any noise, but the cold smoke seal which is made of rubber or brushes, has to seal the gap, therefore touches both the door leaf and the frame, which could cause a noise when the door closes. There are a number of different types of cold smoke seals you could try a different one to see if it is less noisier.

Link to comment
Share on other sites

  • 11 months later...
Guest Guest Capricorn Estates.

Hi been a landlord 25 yrs all HMO properties, it's all down to a good joiner. We fit cold strips is brush / seal strips, almost flush to casing and flush on old doors , where seal is in door. Always mousey and a bit slammy. Fine adjustment twice a year gets it right. Two screws on Briton hinges sorts that. Good joiner or handyman. Cheers.

Link to comment
Share on other sites

  • 4 years later...

I have 2 single 24in fire doors from this 3 storey house. I wish to use them together as a double opening on the middle floor for the Airing Cupboard. I have a bespoke 48in fire frame with fire seals, Sides,Top and all furniture, but :- What do I need to buy for the 3mm gap between the 2 doors? 

Thanks Joy 

Link to comment
Share on other sites

Join the conversation

You are posting as a guest. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...