Fire stopping between ceilings/floors in service riser cupboards/shafts

[Suttonfire]

Hi all,

I note from the following thread that 'guidance' advises that fire stopping is not required around services which are routed vertically inside a riser shaft, provided that the access doors/vertical enclosure is adequately fire resisting.

http://www.crisis-response.com/forum/?action=printpage;topic=4588.0

Please could someone point me in the direction of the guidance which addresses this. I can not find this in the purpose built flats guide or BS 9999.

Thanks

[AnthonyB]

It's in Building Regulations Approved Document B.

[Suttonfire]

Please could you refer me the paragraph were this issue is specifically addressed. thanks

[AnthonyB]

http://www.planningportal.gov.uk/uploads/br/BR_PDF_AD_B2_2013.pdf

Tables A1, B1 and Paras 8.35-8.42

[Suttonfire]

Apologies if I have missed the obvious but I can not see anything which states that service penetrations within riser shafts should not be fire stopped (it is clear from the guidance that any doors to the shafts should be 30 minutes fire rated). Typically I would presume that it is implicit that fire stopping is not needed provided that the access points to the shaft are 30 minutes fire rated (and there being no reference to compartmenting riser shafts on all floors). However, as mentioned in my link to a previous thread in my original message, the use of fire stopping between the floors within protected riser shafts is widespread.

I also note from one of the case studies in the purpose built flats guide a reference to 'provide a good standard of fire stopping to any openings around cables and pipes in common areas above fire doors and within service riser cupboards' (A13.4).

Furthermore, Lacors states that services should be 'enclosed within fire- resisting construction AND fire stopped' (19.7).

[AnthonyB]

Fire stopped around horizontal breaches definitely, not always vertically. It's quite expensive to take a perfectly sealed shaft with a detector at the top and then retro seal it at every floor adding extra detectors as well - nice earner for the contractor, not strictly required (unless BCO's & AI's have been signing off loads of new & recent buildings wrongly).

It wouldn't be a shaft any more if you boxed each floor.

[Mike Buckley]

see http://www.watfordobserver.co.uk/news/10375809.Investigators_still_searching_for_cause_of_Clarendon_Road_fire/?ref=rss

64 Clarendon Rd Watford. fire started in riser at ground floor level.

If the risers are sealed at each floor level would they actually require a detector in the riser compartment? Obviously it would depend on the size of the riser, some of the larger risers I have seen would still be small rooms however the majority of them would just be cupboards. I can see the necessity for detection in an open riser but not for smaller individual ones.