Small gap between door bottom seals.

[Steve123]

I have a set of double leaf fire doors. Both doors have an automatic door bottom seal that is dropped when the button is pressed when it hits the rebate. All gaps between the door and floor are filled except a 15x6mm  gap where the 2 stop so the doors can close properly. Is this acceptable or should there be another piece of equipment fitted to cover this small opening? Many thanks. Unable to upload photo due to file size. 

[Neil Ashdown MAFDI]

Is the blade of the threshold seal continuous along the full length of the door bottom edge?

[Steve123]

Yes, where the two doors meet the small gap is my concern, I have two of those bottom door seal but due to how they are fitted (to allow closing without catching on the other door) it leaves a small gap which is my concern. Finally managed to decrease the image size 

[Neil Ashdown MAFDI]

Thanks for the pic. Makes it so much easier to understand the issue.

In my opinion if the seals are as close to each other as is possible, whilst still allowing the door leaves to self-close without binding on the edges of the seals, then that's as good as you will get.

That is assuming the seals will not fit to the pull side of the doors.

Just another thought, have you checked with the seal manufacturer for advice? They will, I expect, have tested the seals for restricted smoke spread to either BS 476 part 31.1 or BS EN 1634-3. So it would be interesting to see if that test was done on double leaves or single leaf..........or both! 

NB: Automatic drop-down threshold seals are also available to fit into a groove in the door leaf bottom edge. 

Edited June 4, 2019 by Neil Ashdown CertFDI
Additional info

[Steve123]

That is something I would take up with our customer. Potentially a major refurb is going to happen so it wouldn’t be out of the question to suggest these. I will make enquiries with the manufacturer in regard to their test evidence. Thanks very much for the help. 

[Steve123]

I have spoken with the manufacturer who said they are no longer covered by their certifire certificate. The seals are as far as I can tell lorient LAS8009 si. Kind of leaves me without much information to go on. I’ve also had issues tracing a certifire cert of CF658, I’ve tried calling and emailing certifire, the manufacturer of the door has said they didn’t manufacture the door which was a strange one ?. Leaving what appears to be a host of doorsets with no test evidence/data to hand over to the customer. 

[Neil Ashdown MAFDI]

Hi Steve,

Having checked at the BWF website https://www.bwf.org.uk/wp-content/uploads/fdd/Firedor_lit/FDS_Certified_Manufacturers.pdf you can see (below) that, referencing the CF658 Certifire certificate the door manufacturer is Fire Doors Limited.

If there's a BWF-Certifire label on the top edge or hanging edge of the door leaf it should carry the CF number, the name of the door manufacturer and another number with the prefix A. This provides traceability back to the door manufacturer.  If the manufacturer refuses to provide any evidence of fire performance (I don't understand why they wouldn't though) you can access the technical manual and certification for the Strebord door core at https://www.falconpp.co.uk/technical/