Hi, we have recently built a two storey exstension with loft conversion in Oxford and got the building inspector round to sign it off, but she (the nice lady) has told us that the fd30 doors with a good 3mm gap will need to have intumescent strip routered into them.? On the other side of oxford with a different building inspector we constructed a loft conversion and have had it signed off with no mention of the intumescent stip. Have tried to get information on the net but cant seem to find any such laws. Please can you help.!!!

Building Regulations is the law.

Approved Document B (fire Safety) Vol1 (ADB vol1) requires all fire doors to be a full FD30 standard. To achieve this certified door sets should be fitted but in this case the Building Control Officer (BCO) has accepted a nominal fire door.

When a fire door is tested to BS 476 : Part 22: 1987 or BS EN 1634-1: 2000 without intumescent seals the best it can achieve is 20 minutes or less, it needs fire seals to meet the full half hour standard.

So I think the nice lady is right and the other BCO may need to do a little research.

For more information on terms go to http://www.firesafe.org.uk/fire-doors/

ADB Vol 1 go to and download http://www.planningp...ocbvol1/volume1

Best Practice Guide to Timber Fire Doors http://www.asdma.com/bpg.html