• In this Bitesize CPD we will be looking at permissible alterations to a manufactured fire door.

    It seems that many installers are unaware of what you can do and can not and so invalidate their own installation.

    These defects are routinely noted by FCM’s Clerks of Works during their site inspections.



    The photograph above shows a fire door for a riser that was delivered to site too large to fit into the frame. The installer decided to cut it down at the top, removing the hardwood lipping, intumescent strips and label. This action invalidated the fire door certificate and hence the door was no longer a fire door. Unfortunately in this instance there were over 30 doors fitted in this way.


    Permissible alterations:

    You can make some alterations provided they are within the scope of the fire door’s approval documents. This information is also contained in the installation and maintenance instructions supplied with each door leaf.  It is important to follow these instructions carefully to ensure the performance of the door, and hence it certification, is not compromised.

    • You can make some size alterations by trimming the door. These must be within the limits shown in the instructions or CF for the door. There is a trim allowance that can be made to the two sides and bottom edges of the door. You MUST not remove the label on the top edge of the door.
    • You can machine the door leaf and door frame (often referred to as ‘servicing the door’) in readiness for fitting hinges and ironmongery such as locks and latches or to make a doorset. However the hinge size, position and number must be as shown in the instructions or CF for the door. The hinges used must also be CE marked for use on a timber fire door. On some doors the hinges may need intumescent protection.
    • The latch must be CE marked for use on a timber fire door and the size must not exceed that shown in the instructions or CF for the door. On some doors the latches may need intumescent protection.
    • All recesses for ironmongery in fire-resisting timber doors should be performed as accurately as possible to avoid creating unnecessary voids.
    • Clearance holes for keys, cylinders and spindles should be no larger than the sizes specified on the hardware manufacturer’s fitting instructions.
    • You can hang the door in your own door frame. However the frame MUST be of the correct material allowed for the door leaf. It must also be GREATER than the minimum section size and density indicated in the instructions or CF for the door.


    What you can not do.

    • You must NOT trim the door by more than the allowance specified in the instructions.
    • You must NOT cut apertures or glaze the door UNLESS you are Approved to carry out this work.
    • You must NOT cut apertures for air transfer grilles UNLESS Approved to carry out this work.
    • You must NOT hang the door in a configuration that is not permitted.
    • Do NOT assume that 2 single leaf doors can be hung as a pair of fire doors.


    As a general rule:

    • Softwood is acceptable for FD30 doors.
    • Hardwood is acceptable for FD60 doors BUT some hardwood species may not be used.
    • MDF frames are NOT always allowable and MUST be checked against the door leaf’s certificate.
    • You can fit a door closer to the door leaf/frame but it MUST be CE marked AND Certifire Approved for use on the type of door you are using.
    • If the door has been glazed, ensure that the door closer selected can be used with the glass area that has been fitted.


    • **Note: On many overhead closers there is a restriction preventing them being used on doors where the glass area is more than 20% of the total area of the door. Also where un-insulated (Integrity Only : stamped ‘E’) glass is used.


    • When fitting a doorset, or fire door frame, into a wall you must ensure that the wall construction is allowed within the CF for the door. You MUST ensure all the gaps between door frame and wall are filled with the a material designed and tested for this use.
    • You MUST ensure that gaps between the door leaf and door frame do NOT exceed 3mm ( /-1mm) at the top and side edges of the door leaf (or as stated in the door leaf manufacturer’s instructions). Threshold gaps MUST be as shown in the instructions or CF for the door.
    • You can produce a FD30S or F60S ‘smoke control door’ but it MUST be fitted with the correct CE marked and Certifire Approved smoke seal. Please check the CF for the SEAL to confirm that it can be used. Take note of the threshold gaps required for smoke doors.
    • You can fit a letter plate but you MUST first check that these are permitted in the CF for the door leaf.
    • The aperture for a letter plate may be cut on site by NON- approved staff. However, the letter plates fitted MUST be approved for the appropriate application and fitted strictly in accordance with the specification detailed in the CF for the letter plate


    For any configurations other than single acting single leaf (SASL), you must check that the configuration you want to produce is allowed in the instructions or CF for the door. You must also check that an unlatched configuration is allowed if you do not plan to fit a latch.


    Please note: If you fail to comply with any of the above, the certification is no longer valid. You will bear legal responsibility for proving that the product you supply is a fire door.


    Below is a video about installation and testing of both compliant and non compliant door sets. Please do watch it – it will take 8 minutes but will leave a lasting impression.



    Steve Farrell 
    T: 07714234380
    E: stevefarrell@fcmltd.co.uk 
    L: linkedin.com/in/stevefarrellfcm

    Fox Curtis Murray are a building consultancy specialising in providing Clerks of Works services and Quality Control.

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