fire door seals: with or without brush

[Guest garrywilk]

Hi, I'm getting confused. Is intumescent strip the same as a fire door seal and do I have to have a brush on the seal as well? I am tasked with purchasing new fire doors for a HMO. Any advice is welcome

Garry

[Tom Sutton]

A fire door provided with intumescent strip, when activated, which will prevent hot gasses passing through any gaps and if you have cold smoke seals (brushes) fitted that prevent cold smoke passing through the same gaps. Check out http://www.firesafe.org.uk/fire-doors/ for more detailed information and download the The Best Practice Guide from publication section of http://www.asdma.com/

A door with only intumescent seals is designated a FD door and if cold smoke seals (brushes) are installed it is designated a FDs door. The decision whether a FD or FDs fire door is required is made as the result of the fire risk assessment. If there is any doubt I would suggest you fit both.

[Safelincs]

Hi Garry

In general it is best to choose an intumescent fire door seal with an integrated brush to protect against smoke and fire. There is only one exception: If a building has fire detectors or smoke alarms only in the escape routes (eg corridors), then the detection of a fire in one or the rooms depends on a trace of smoke escaping through the gaps around the fire doors from the room into the corridor.

As you can imagine, however, this is not a particularly safe design! It is, of course, a lot safer to have detectors in the rooms as well.

Harry

[Guest Annbes]

Is the gap crucuial for fitting a fire door seal, as the hinge gap is only 2mm wide?

[Tom Sutton]

The gap for a fire between the door and frame should not exceed 4mm, so 2mm is ideal. However it still requires intumescent fire door seals to be fitted and maybe cold smoke seals (brushed seals) which will depend on its location.

Check out http://www.firesafe.org.uk/fire-doors/

[Guest Sally H]

The British Standard Code of practice for fire door assemblies (BS 8214: 2008) notes that 'a typical gap to achieve good fire performance is between 2mm and 4mm' and that, ideally, the door "should be hung to give an equal gap across the head and down both jambs". The Intumescent Fire Seal Association (IFSA) advises that the hinge gap on your door is fine and that generally it is better to err on the side of caution; a gap that is too large is much more of a concern. When fitting the seal, it is important to ensure that the right amount is used to suit the individual design and configuration of the door; as noted by the Architectural and Specialist Door Manufacturers Assocation (ASDMA) in their Best Practice Guide to Timber Fire Doors, too much on the hanging edge of an unlatched fire door could generate enough pressure to force the leading edge open in a fire situation as, depending on its type, an intumescent seal can expand by 5 - 10 times its original size.

[Guest DanielFel]

Hi.

When retrofitting fire and smoke seals to an existing fire door do I require seals to the inner vertical sides of a double door where the door leaves are rebated, therefore when closed there does not appear to be a gap in the middle? Currently I have assumed all outside edges of the doors perimters are to be sealed including threshold but not the inside edges where the two door leaves meet, is this correct or can you please advise?

[Sally H]

When retrofitting intumescent / smoke seals to an existing fire door, both vertical edges and the top horizontal edge of the leaf must be sealed. It is not usual to seal the threshold. In respect of double doors, the rebate alone is insufficient to prevent the ingress of 'cold smoke' around the door edges in the early stages of a fire. As a fire develops, and as noted in the ASDMA Best Practice Guide to Timber Fire Doors, the meeting edge between double leaves is particularly vulnerable because relatively small differential movement in the door leaves through exposure to heat and flames will greatly increase the possibility of integrity loss due to gap formation through distortion. The role of the intumescent seal is to control this distortion; the Intumescent Fire Seals Association (IFSA) guidance on the upgrading of joinery doors notes that fire doors normally fail by distortion, rather than burn-through. The IFSA guide further notes that seals must provide low closing friction to prevent the seal from inhibiting the door from closing effectively and fully.

[Guest Suzanne]

I haven't found mention of the gap between the door and the floor - Is it not covered by the 2-4mm rule?

[Tom Sutton]

BS 8214:2008

Under-door (threshold) gaps should be in accordance with the manufacturer’s installation instructions for the particular doorset design. When fitted, smoke seals should give an even contact with the floor but should not exhibit significant increased frictional forces that could interfere with the closing action of the door.

[Guest Paul]

I wonder if you could help please, has there been any new fire safety legislation recently? I live in a six year old block of 34 leasehold retirement appartments, and throughout this time there has always been wide gaps under the doors to the flats, as fitted by the developer. Only now have these gaps become an issue and smoke brushes are to be fitted. I understand the point of not having gaps under the doors but I would have thought this should have been dealt with by the developer during the time of construction. Because of this alledged new law ( and that the landlord says we are now classed as a Hotel or B&B ) we are being asked to pay a high bill for the work. Surely gaps under doors has been part of the fire safety regulations for quite some time? We feel that the developer shoud be responsible for these costs.

Thanks, on behalf of the residents, I hope you can help.

[Guest lily]

Hi we have just had 18 fire fitted and they have no brushes round the fire door is this ok

 

[Tom Sutton]

If the fire doors are designated FD30/60s that means they require to be fitted with intumescent seals and cold smoke seals. The appropriate guidance is BS 8214:2008 Code of practice for fire door assemblies and this British Standard changed the advice on threshold gaps, which suggested you use manufacturer's guidance which I believe required smoke seals if the gap was greater than 3mm.

Who pays is between you and the landlord.

[Guest Khairul]

Hi, 

Can the intumescent seals covered by other finishes such as veneer ? Or just leave the intumescent seals expose

Tq

 

[Guest KEVIN FDIS]

Some intumsecent manufcaturers have undertaken fire tests after painting over their seals, to check that overpainting is ok. Suggest you check with your preferred manufacturer 

[Tom Sutton]

There are various type of intumescent seals and certain types can be concealed under the hardwood door lippings. You should contact the experts in this field, like envirograf for their advice.

[Neil ashdown]

Hi Tq,

Tom is correct sometimes seals are concealed but you should check with the door manufacturer and the seal manufacturer because different types and sizes of seals react to intense heat at varying degrees of temperature and at varying rates of expansion. You can buy seals from some manufacturers in varying colours and veneer finishes to compliment the door  or frame decoration.

[Guest Dave]

I need to replace missing seals to some riser cupboards in an office block. The door frames are already rebated for fitting of the seals however there are 2 rebates. Should i fit 1 seal with brushes and 1 without?

What is the purpose of doubling up the seals?

[Tom Sutton]

Most probably the double intumescent seals is because the fire doors are FD60s fire doors but you only require one cold smoke seal.

[Guest Mourad Aberkane]

we have a canteen its separated to two part (Dining & Kitchen area) the kitchen area is composed by many rooms (cooking rooms. Bakery , storage rooms, offices ,,,,,) I want to know where the fire doors are required and is it acceptable to have a fire door without certification label

[Tom Sutton]

You would most probably require a fire door between the kitchen and the dining room, the rooms in the kitchen, it would depend on the layout and the risks posed by each room. If you are fitting new fire doors then they should be certificated (carrying a certification label or plug) if they are existing fire door then they should be assessed by a competent person who can provide documented proof.

[Guest Deny]

Hi can you let me know please I'm living in a 2 story purpose built flat built in the 70 which have self closing fire doors and other means of escape via balcony door do we still need fire strips put in thanks deb

[Tom Sutton]

If the doors are BS 476 part 8, substantial, well fitting then intumescent strips may not be required but if new doors are fitted then they should be BS 476 part 22 and intumescent strips will be required, if there is any doubts fit the strips.

Check out  Fire safety in purpose-built blocks of flats  

[Guest s1131]

Hi,

 

I was wondering wether anyone could help. Do you know if its possible to upgrade a recently fitted FD30 composite GRP door to an FD30S door by retrofitting intumescent strips and smoke seals on the door?

 

Thank you 

[AnthonyB]

Upgrading work is preferred to the frames - you can get adhesive smoke seals from Envirograph, but there would be no test certification for the upgraded installation.