Fire Doors for open plan staircase solution

[tracey]

we are looking for a solution to creating firedoors that will comply with Building Regulations regarding fire protection of an open plan stairway on the ground floor due to new loft conversion, to be used as a bedroom, in a 2 storey residential terrace house.

the open plan stairway opens into the living room and the narrow hallway to the front door. the opening measures approximately 6ft w x 8 ft h.

have been told the only option would be to block in the stairway on the ground floor and put in a small fire door (as Building controls won't allow fire sprinkler system as originally suggested).

would like to use either a large double or even a concertina fire door to fit across the space, but understand there is an issue with making the seals for this meet the 30 mins fireproof requirements.

any advice on this would be really appreciated. many thanks

[kurnal]

Sprinklers may offer some help in this situation but as they are essentially operated by heat there is a high chance that in the event of a smouldering fire the stair could be smokelogged before the sprinklers operated.
In addition if the fire is shielded say bey a table, the staircase may be untenable due to smoke.
If you are determined to maintain the opening and prepared to install sprinklers, You could suggest a full fire detection system and a drop down fire curtain across the opening. The curtain would be linked to the detector system. The curtain would be half hour rated and contained in a 150mm box at ceiling level. A curtain of this size may cost you a couple of thousand quid- do a google search for fire curtains.

If you are determined to maintain the open plan stair, large folding firedoors are likely to be left open most of the time and therefore a useless investment

[Dinnertime Dave]

My main question to the Building Control Officer is why won`t they accept sprinklers. ADB (Section 2.20b) gives it as an alternative solution in the open plan area coupled with a fire resistant door and partition seperating the ground and first floor and an escape window at first floor level. however the cooking facilities should be seperated from the open plan area by fire resistance.

The alternative is to seek a variation from Building Regs the BCO will normally consult with the Local Fire Safety Officer. We recently had similiar circumstance in a barn conversion (although it was a retrospective application) the solution involved seperating the ground and first floors and providing an escape window and an advanced level of smoke detection.

Remember that the Approved Document B is only a guide and alternative solutions may be acceptable.

[PhilB]

Sprinklers would not, in my opinion, provide the solution here. It is not a good idea to escape through a room on fire even if sprinklers are provided.

Yes I know HTM88 suggests this is acceptable but I think the author was misguided on that point.

The recommendations in ADB that Dave refers to requires separation together with sprinklers so that an escape window can be reached on the first floor.

[John Webb]

I agree with Kurnal (post #2) that if there was a smouldering fire then there would be the risk of smoke-logging the staircase prior to sprinkler operation. But with the low heat output of a smouldering fire this would take some time and domestic detectors appropriately installed should give adequate warning prior to stair smoke-logging.
With a rapidly developing fire and without sprinklers, the detectors would not give sufficient warning prior to the escape route down the stairs becoming impassable. But with sprinklers, the fire severity will be rapidly reduced and smoke cooled to the point where it is unlikely to rise up the stairs. But it will still affect the upper part of the house to some degree in the early stages of the fire - this is where Dinnertime Dave's post (#3) comes in regarding separating the ground and first floors. This seems to me to be a 'reasonable and practicable' method of overcoming the perceived problem.

[tracey]

many thanks for all your advice. sadly our council have refused to accept sprinklers so this is a complete no go. they say that Haringey council always refuse permission for sprinkler systems so have advised us not to pursue this option.

they have also refused to accept the 1st floor bedroom window as an acceptable escape window because it has a bay window underneath (even though there is only a tiny garden before the road which would allow easy emergency ladder access)! we are also putting velux escape windows in the loft conversion front and back for our own peace of mind although the council again will not allow these as acceptable escape windows (because of the bay window on 1st floor etc).

we researced the fire curtain solution but as these take several minutes to close. we would prefer actual doors that we can immediately close to hide the living area from the staircase as i work from home and clients walk up the stairs each day.

[PhilB]

But with sprinklers, the fire severity will be rapidly reduced and smoke cooled to the point where it is unlikely to rise up the stairs. But it will still affect the upper part of the house to some degree in the early stages of the fire - this is where Dinnertime Dave's post (#3) comes in regarding separating the ground and first floors. This seems to me to be a 'reasonable and practicable' method of overcoming the perceived problem.

It most probably will rise up the stairs John but more importantly the occupants may need to pass through the room with a fire in it.

This is not a good idea even with sprinklers and I am a little surprised to see the inappropriate use of them recommended.

[Dinnertime Dave]

Phil refers to my post

The recommendations in ADB that Dave refers to requires separation together with sprinklers so that an escape window can be reached on the first floor.

Yes agreed, but my main point is that if ADB gives this as an alternative why won`t the BCO accept it.  

Also, Tracey you say that they have also refused to accept the 1st floor bedroom window as an acceptable escape window because it has a bay window underneath. I would have thought that this is a better solution to enable a person to escape from a window onto the top of the bay then down thus reducing chance of injury. I`ve heard objection due to Conservatories being in the way but not a bay window.

The alternative we accepted in partnership with the BCO was prior to April 07 ADB we considered sprinklers but  we concluded that they didn`t add significantly to the safety of the occupier when judged against a very high level of detection and fire resistance at the head of the stairs from the ground floor.  both solutions still required the occupier to escape from a first floor window.

[John Webb]

PhilB,
I was agreeing with all of Dinnertime Dave's suggestion, viz isolation between ground and 1st floor, so that the escape window at 1st floor level can be reached.
Bearing in mind tracey's comment re the position of this window, I cannot see anything wrong with this approach.
The principle problem seems to be the unwillingness of a local authority and its BCOs to accept solutions agreeable to both ADB and others to overcome a slightly non-standard problem in a building.

[kurnal]

I cant see why a bay window should preclude a window exit above it compared to a standard window? Conservatories are of course something else. Anybody enlighten me?

[wee brian]

Tracey was originally asking if she could get fire resisting double doors - the answer is yes.