hi we are doing remedial work on fire doors and adding hardwood lips to the bottoms of the doors to create 3 to 8nm threshold gaps. Can we double the lips EG 2 8mm lips to a 20mm gap to create 4mm or would we have to buy lips at 15mm. we only have 8mm lips thats all

Lipping must be of a suitable hardwood and fixed with an adhesive appropriate to the door fire rating and type of timber core/rail.

Lipping should be one piece, rather than two pieces used double thickness.

For FD30 minimum 6mm thick and maximum 19mm thick with maximum 2mm profiling at the corners.

For FD60 minimum 6mm thick and maximum 15mm thick with maximum 2mm profiling at the corners.

On 02/06/2021 at 16:07, Neil ashdown said:

Lipping must be of a suitable hardwood and fixed with an adhesive appropriate to the door fire rating and type of timber core/rail.

Lipping should be one piece, rather than two pieces used double thickness.

For FD30 minimum 6mm thick and maximum 19mm thick with maximum 2mm profiling at the corners.

For FD60 minimum 6mm thick and maximum 15mm thick with maximum 2mm profiling at the corners.

Hi Neil,

Where have you got this information from? I cannot find anything in BS8214 or ASDMA

On 02/06/2021 at 16:07, Neil ashdown said:

Lipping must be of a suitable hardwood and fixed with an adhesive appropriate to the door fire rating and type of timber core/rail.

Lipping should be one piece, rather than two pieces used double thickness.

For FD30 minimum 6mm thick and maximum 19mm thick with maximum 2mm profiling at the corners.

For FD60 minimum 6mm thick and maximum 15mm thick with maximum 2mm profiling at the corners.

Hi Neil,

Where have you found the information on the thcickness of lippings you can use? Is it based on differing manufacturers and what they use, I only ask as I have numerous doors that require lipping and in most cases the lipping required is thicker than the lipping fitted (which will be removed). If I use a thicker lipping then I would like to demostrate to the client where the information has come from.?

Lipping thickness spec has come from https://www.falconpp.co.uk/downloads/  but clearly applies to those particular doors so consult the door leaf manufacturer where that's possible.   However, where you are unable to do so the information about lipping thickness, adhesives and timber species can be applied as good practice.

Hi. Appreciate issues with certification but wanted to check if there is a minimum height for a fire door ie can you angle the top corner and maintain escape requirements. thanks. Max

Does cutting fire door corners to suit roof line compromise escape? ie is there a min height? thanks

Escape provision would be dependent on Building Regulations where they apply.   Where they don't apply, the Fire Risk Assessment should deal with the issue.   In terms of cutting the top of a fire door at an angle, this is very likely to affect its fire resistance performance.  Always check with the door manufacturer before cutting!

Can you add hardwood lipping to the door?

That depends what the certification data sheet or other fire performance related documentation requires.  Is any available?

what glue would you recommend to use when adding a plant on the bottom of a door

I would use a urea formaldehyde based adhesive.

I have an original 30min fire door leaf with fire and smoke seal rebate  in the door, with an original door frame that can't be removed, as its in an old carehome . The top of the door leaf on the lock side has a gap of 6mm which slopes to the other side to  the 3 mm gap on the other side. There is lipping on the top of the door already and no fire certification on the top of the door,  so can I re-lip the top of the door leaf and scribe it into the door frame using the correct materials as as nominal fire door rule to upgrade the door to have the correct door gap all around.

Removal of existing lipping and re-lipping a timber-based fire door with suitable hardwood and using suitable adhesive is a valid option for remediation of excessive door leaf to door frame gaps.  It should be carried out be a suitably competent person.

Reading this post I am confused about nominal door and certified door. When you modify a certified door, then it becomes a nominal door, for example if you drill a hole into it and then want to fix it then it's a nominal door at best. I've seen datasheets that say that even non certifire certified installers can install a certifire fire rated letterbox, which will require a much bigger hole! Would the door certified or nominal at that point? If it's stated in the datasheet that the letterbox is allowed shouldn't it be still certified?

Thank you

There's much confusion on this point.  It is not possible for a certificated fire door to become a nominal one.

Certificated fire doors can have many items of hardware fitted but the hardware must be compatible with the fire door leaf. This means the installer must follow the requirements of the certificate and data sheet for the fire door leaf when fitting the hardware; handles and letter-plates included. 

Where an installer fits an item of hardware that is not compatible, reduces the size of the door by more than permitted or makes a repair such as replacing a lipping then the door could become a 'non-compliant certificated fire door'. This is because the scope of the certification does not cover that modification.

Before modifying the door one should check with the manufacturer to see what the scope of the certification allows. This is not to say that a fire door should not be repaired but to emphasize that the scope of the certification is intended to cover the manufacturing of the door by factory production control rather than repairs to the door.

Hi I have been sent to close gaps on fire doors I have been told to add another lipping on an already lipped door to close the gap is this okay to do ? 

If the fire door leaf (or fire door-set) can be identified to its certification / manufacturer, the technical department at the door manufacturer will be able to advise what work may be done without compromising the fire resistance performance certification. 

Where the door cannot be traced to any certification or manufacturer an additional lipping should not be added to the existing one, instead the lipping should be replaced using the correct dimensions and density of hardwood and suitable adhesive. The work should be carried out to a 'joiners shop' standard. 

Edited May 31, 20233 yr by Neil Ashdown MAFDI
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