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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Fire Safety => Topic started by: Chris Houston on August 22, 2007, 10:46:00 PM

Title: Timber Fire Escapes
Post by: Chris Houston on August 22, 2007, 10:46:00 PM
http://news.bbc.co.uk/1/hi/england/cornwall/6953427.stm

I note the comments about the timber fire escape.  I've not seen a timber fire escape.  What are people's views on these?
Title: Timber Fire Escapes
Post by: Midland Retty on August 23, 2007, 09:17:37 AM
Depends really ... Risk Assessment time!

Members of the general public always regard wood as being readily combustible.

Infact during a radio phone in on the Radio2 Jeremy Vine show some callers were amazed to hear that a wooden staircase was installed at the recent hotel fire in Newquay. I agree that its not commonplace but is it necessarily wrong? The Fire Inspector obviously didn't think so.

Yet as the Cheif Fire Officer pointed out - the wooden escape staircase was successfully used during the evacuation.

At the end of the day it would require a substantial heat source to ignite it potentially and so long as there wasn't anything that could impinge onto it (within the time it took to escape) and there were alternative escape routes available I cant say id be too worried about wooden escape stairs.

As with metal staircases everything within 1.8 meters around it should be suitably FR
I accept radiant heat might play a part but in a building with early warning the staircase shouldn't become untennable until well after people have escaped.

Biggest problem I can forsee is the maintenance of it (ie poorly maintained and going rotten)
Title: Timber Fire Escapes
Post by: kurnal on August 23, 2007, 09:23:11 AM
Timber external escapes were common in the early 1970s when the fire precautions act suddenly led to improved fire safety standards in many older type buildings. The big problem is structural integrity as they rot, coupled with a buildup of verdigris that can make them slippery unless treated with a non slip cover that makes them rot faster.

The history means that 35 years on many of them have now rotted away and been replaced with steel.
But if they are in good condition and up to the job there is no reason to replace them as a matter of course in my opinion. Just keep a close eye in the condition.
Title: Timber Fire Escapes
Post by: Tom Sutton on August 23, 2007, 09:43:19 AM
Kurnal has hit the nail on the head. I remember a colleague placing a prohibition order on the first floor of a factory not because it was a timber external escape but because it was in a state of collapse due to rot. Also in the rain they were a nightmare because they were so slippery.
Title: Timber Fire Escapes
Post by: firestop on August 23, 2007, 11:43:14 AM
Isnt it surprising that its only just under 2 years ago that the Fire Precautions Act certificate went by the board and now we have lots of big fires.

I cant understand how a wooden fire escape stair could be so involved in fire unless the base had become a storage area for wheelybins and rubbish. A large fire source at the base would certainly create enough heat to fire the timber structure.
I hope that the doors onto the stairs were fire resisting and that all all associated glazing was of the same fire resisting standard.

The Fire Brigades now dont have the same inspection regime they used to have.
Title: Timber Fire Escapes
Post by: Chris Houston on August 23, 2007, 12:05:41 PM
Presumably storage under metal stairs resulting in a fire would be equally dangerous?
Title: Timber Fire Escapes
Post by: jokar on August 23, 2007, 12:24:43 PM
Firestop, risk assessment has been with us for a long time and in the fire safety arena since 1997.  Subject to popular opinion there have not been additional fireor larger fires or more fire deaths in commercial premises in this time frame.  The comments in the posts with regrad to rigourous inspection for timner escapes is correct.  Do not forget this was a Hotel subject to having a Fire Certificate which allowed the timber fire escape and it was used sucessfully during the fire.  The reason it and the hotel burnt was the intensity of the fire and the investiogation will eventually give us the reason for this.  Metal stairs in the same position may well distort under heat and become unusable due to extreme temperature.
Title: Timber Fire Escapes
Post by: AnthonyB on August 24, 2007, 04:27:26 PM
Although risk assessment existed since 97 (although it only moved to cover certified premises in 99) my experience was that most (not all) enforcing bodies stuck to certificate enforcement (& it's 'frozen in time' drawbacks) until the RRO usually simply appending a letter or leaflet reminding occupiers of their duty to meet the FP(W)Regs & most (but not all) prosecutions during this time were still under the FP Act,hence why theres been little change in stats since '97 .It's only from October 06 onwards should we be looking at cases & statistics to determine the RRO's effectiveness
Title: Timber Fire Escapes
Post by: wee brian on August 28, 2007, 01:31:42 PM
Conjecture - but here we go.

The Original Hotel had dreadful means of escape - When the FPA came in they installed the two external stairs. These probably reduced the number of casualties from 50 odd to 3.

The million dolloar question is - was there any FR glass in the windows that faced the stairs. If there was it didnt work very well but I doubt there was any at all.

Did this get picked up in the risk assessment???????????????????.
Title: Timber Fire Escapes
Post by: nearlythere on August 28, 2007, 05:33:02 PM
Do not forget that Fire Certificate standards do not prevent any building, including its protected stairways, from burning down. The Certification standard tries to ensure that all persons can escaped before this happens.

The report on the incident will be very interesting for all involved in fire safety.
Title: Timber Fire Escapes
Post by: wee brian on August 28, 2007, 08:06:53 PM
Absolutely - The pictures on the TV are of a fire in the stage which is of little interest to us fire safety bods. What worries me is the references to the stairs burning as people escape - that aint meant to happen. My money is on plain glass in the windows by the stairs.
Title: Timber Fire Escapes
Post by: AnthonyB on August 29, 2007, 01:01:46 AM
It's not unusual to find retrofitted external stairs without glazing upgrades, whilst many clients are happy to repair, weld & repaint the stairs if in poor order (which isn't that cheap) they always decide to overlook glazing issues - if non FR glazing is found to have contributed in this case then they may well think again once presented with the evidence
Title: Timber Fire Escapes
Post by: wee brian on August 30, 2007, 11:36:26 AM
I hope somebody checked before the walls were knocked down
Title: Timber Fire Escapes
Post by: saddlers on August 30, 2007, 03:25:20 PM
Whilst on this subject, I have often wondered about the fact that glazing adjacent to an external stair is not required to be "insulated" fire resistant glazing. I know the heat should dissipate due to the external location, but you have to wonder whether radiated heat could affect a timber stair, and more importantly affect the people descending the stair!!

Especially when you consider you could still have timber external escape stairs in certain scenarios as detailed in Approved Document B, although I have to admit you don't see them very often.
Title: Timber Fire Escapes
Post by: kurnal on August 30, 2007, 10:18:12 PM
When I encounter unprotected glazing alongside external fire escapes I do not recommend it be upgraded in all circumstances.

In sleeping accommodation, according to national guidance,  all means of escape staircases should be protected routes so I always recommend those serving sleeping accommodation be upgraded.

But for commercial and industrial premises the requirement is to ensure a fire cannot simultaneously take out multiple escape routes, and indeed in a building with two internal staircases often only one needs to be a protected route. So the same would hold good if one of the stairs was external- as long as the staircases have sufficient separation from each other  and a fire cannot take out both routes plain glazing may be fine.

Comments welcome.
Title: Timber Fire Escapes
Post by: CivvyFSO on August 31, 2007, 01:54:35 PM
I have looked at it that way also. So long as the alternative is seperated sufficiently so a fire cannot take out both then it should be ok.

BUT... I am sure that the hotel in Newquay SHOULD have had a protected internal staircase and anybody risk assessing protecting the external with FR glazing etc might have used the defence that a fire cannot take out both staircases.
Title: Timber Fire Escapes
Post by: Pip on August 31, 2007, 03:49:25 PM
If the stairs are required for means of escape,they need to be protected (enclosed if internal,protected with fire doors/glazing in accordance with ADB if external.)Being seperated from each other is not sufficient.
Title: Timber Fire Escapes
Post by: wee brian on August 31, 2007, 08:09:18 PM
Yes - in a new building - but the question is - when would I upgrade all the windows in an exisitng building? - that's a risk based judgement.
Title: Timber Fire Escapes
Post by: AnthonyB on August 31, 2007, 09:51:56 PM
Just because it was OK in the past (when they didn't know any better) doesn't mean it should be OK now. But as you say prioritising the need can be difficult as responsible persons do not have bottomless pockets.

I would consider sleeping accomodation such as hotels a high priority though.
Title: Timber Fire Escapes
Post by: wee brian on September 01, 2007, 09:29:57 AM
Me too
Title: Timber Fire Escapes
Post by: Ken Taylor on September 03, 2007, 12:03:15 AM
Protection of all external stairs forming part of the MoE has got to be better. There can be access from different storeys and stairs tend to traverse the face of buildings at diagonals so that persons joining them at a higher level may well not appreciate the proximity of the stair to the location of the fire at a lower level and so not choose the safer option of the available routes.
Title: Timber Fire Escapes
Post by: kurnal on September 03, 2007, 07:57:47 AM
Thats a good point Ken. And having chosen the wrong route in such a case it may not be possible to get back into the building if all doors have self closers and are secure from the outside.

But again what if on its traverses across the face of the building the escape route passes across a different fire compartment? A fire exit in a compartment wall is usually classed as a storey exit? We dont tend to look at fire safety provision beyond the compartment involved in fire.

Many of the old mills often had extensive external escapes such as you describe, often steep and narrow- typically 500mm. and invariably unprotected. If I come across these in industrial or commercial use I may also not ask ask for the glazing to be upgraded if the sprinklers are still operational.

Has anyone come across georgian wired glazing in uPVC frames? Was any certification available? I have seen this regularly and never yet seen any evidence of fire performance.
Title: Timber Fire Escapes
Post by: wee brian on September 03, 2007, 08:51:30 AM
Georgian wire in UPVC - Not a hope.
Title: Timber Fire Escapes
Post by: Hertsmere on September 03, 2007, 08:56:26 AM
Dear all

We are moving to our offices to a building that was built in 1975.
We will be occupying the ground and first floor.

The only fire escape is a wooden staircase that looks pretty ok.

Does this (a wooden staircase) confirm under Fire Safety regulations and will the insurer insure us?

Your help is much appreciated.

Pradip
Title: Timber Fire Escapes
Post by: CivvyFSO on September 03, 2007, 09:07:22 AM
Do you mean the only internal staircase is made from wood, or you have a normal internal staircase AND an external wood one?
Title: Timber Fire Escapes
Post by: kurnal on September 03, 2007, 09:09:52 AM
Good point civvy- I had read it as an external but it may be a single internal staircase.

Hertsmere- You will need to carry out a fire risk assessment of the new offices.

This will take into account the size of the buildings and how far people have to travel to reach the nearest exit,  the layout and arrangement of the staircases, whether the internal staircase is open plan or enclosed by materials that will give some protection to people from a fire as they leave the building.

If it is an external wooden staircase is it protected by fire resisting wals, windows and doors beneath or adjacent to it.

If the wooden staircase is in good condition, not rotten or covered in green slime, and if there is enough borrowed lighting for people to see their way down it during working hours it should be ok.
Title: Timber Fire Escapes
Post by: Dinnertime Dave on September 03, 2007, 01:30:26 PM
Quote from: kurnal
When I encounter unprotected glazing alongside external fire escapes I do not recommend it be upgraded in all circumstances.

In sleeping accommodation, according to national guidance,  all means of escape staircases should be protected routes so I always recommend those serving sleeping accommodation be upgraded.

But for commercial and industrial premises the requirement is to ensure a fire cannot simultaneously take out multiple escape routes, and indeed in a building with two internal staircases often only one needs to be a protected route. So the same would hold good if one of the stairs was external- as long as the staircases have sufficient separation from each other  and a fire cannot take out both routes plain glazing may be fine.

Comments welcome.
Whilst I agree with kurnal`s first point of not recommending an upgrade in all circumstances, the length of an escape route must also in my opinion be taken into account what ever the purpose group of the building. if a person escaping a fire is committed to an escape route then that person should not have to retrace their steps due to a lack of FR glazing.
Title: Timber Fire Escapes
Post by: nearlythere on September 03, 2007, 05:08:24 PM
Quote from: Hertsmere
Dear all

We are moving to our offices to a building that was built in 1975.
We will be occupying the ground and first floor.

The only fire escape is a wooden staircase that looks pretty ok.

Does this (a wooden staircase) confirm under Fire Safety regulations and will the insurer insure us?

Your help is much appreciated.

Pradip
A fire risk assessment would determine whether you need a "fire Escape".
The existance of some exit doors and stairways does not mean they are necessary for MOE.
Title: Timber Fire Escapes
Post by: Ken Taylor on September 03, 2007, 09:08:47 PM
Never seen Georgian-wired in uPVC, Kurnal - but plenty in metal and wood. Schools have traditionally been full of the stuff - said to be both for fire resistance and 'safety glazing' - and no BS compliance evidence for that either.
Title: Timber Fire Escapes
Post by: kurnal on September 03, 2007, 09:11:23 PM
I have recently come across three cases of georgian wired in PVC frames on external escapes so it may be a growing trend- in Walsall, Oldham and Mansfield
Title: Timber Fire Escapes
Post by: wee brian on September 04, 2007, 08:51:20 AM
I spose its better than nothing - but only just
Title: Timber Fire Escapes
Post by: saddlers on September 04, 2007, 01:03:31 PM
I used to work in a PVCu manufacturing mill, and have seen PVCu windows in several fires, believe me the Georgian wire would not stay put for long. The PVC melts, and unless there are mechanical joints the reinforcement within the frame will just fall out. PVC frames literally disintegrate in a fire scenario. My money would be on the georgian wire glass being in tact lying on the floor!!

I think it is a case of people thinking of the glazing issue without considering the frame it is sitting in. With the amount of contractors that have asked me the question, I have no doubt that there will be several examples of this construction being used (albeit with good intentions).