Lakanal House - a Case Study
David Ware - Fire Risk Consultancy Ltd
In 2006 a serious fire resulted in the deaths of 6 people all of whom were not in the room of origin. This case highlighted the importance of good fire safety management in premises and brought into question the “Stay put” policy.
Lakanal House was constructed in 1950 and was considered a state of the art building. It was predominantly council rented with a dozen leasehold out of 98 flats in the building. The building was 16 storeys high with 14 accommodation storeys. 1st floor through to the 14th were accommodation. There was a undercroft at ground level, plant lift motor extraction and machinery on roof.
Access to building was on every other floor odd numbers . It had escape balconies on every even number floor providing alternative escape from each flat. The corridors and balconies all fed into a single staircase/single stair shaft. There were two lifts , however, one of these lifts was undergoing refurbishment so was completely out of action. There was also a dry rising main in the building.
All of the common spaces were cross ventilated. This was a system that was accepted at the time of the build however not generally accepted. The flats were arranged in a scissor arrangements and the building had a single staircase.
The design principle of the flats were that every accommodation room except bathroom should have 2 means of escape to get you out of flat and out to a point of safety.
The building was built to the county council means of escape in case of fire 1954 guidance and this was the first piece of guidance that allowed a building of lakanal’s height to be built with one stairwell to get down and out of building. This was on the proviso that you had cross ventilated corridors and that you had 2 means of escape from every accommodation.
The building had serious refurbishment in the 1970s external façade of the building. The existing façade was replaced with a timber framed set with asbestos panels. In the 1980s couple of pieces of work carried out. Security doors were installed between the lobbies and the corridors due to security issues. There was a requirement by the Local Authority that there was an open vent in the security doors that maintained the effectiveness of the cross ventilation. It required in each of doors ½ m2 of permanent open vent and an extra 1 m2 of manually openable vent in case smoke was need to be cleared.
The door had 2 smoke vents put in that look like georgain wired glass but these were actually the vents however the area was only 1/3rd of a square metre and no additional option of increasing the area another 1m2 which reduced the effectivess of the cross ventilation.
A suspended ceiling in the corridor was installed to accommodate the new services and hide them and this was continuos along the whole length of the corridor. The problem was, the false ceiling was also made of softwood with panels of unknown materials. These panels were however replaced 12 months later with chipboard panels with a melamine laminate that were fire retarded and fixed onto the softwood timber boards.
Planned preventative maintenance project was proposed in 2006 and therefore there was NO full requirement for building regulation approval, no need to involve building control as there was to be no material alteration of the building.
However, at some point at the inception of this project it was upgraded to a decent homes project. One serious issue was the removal of the façade of the building which was a timber and asbestos system and replacement with an aluminium system with a composite panel, particularly in the lower third of each flat.
The fire started in flat 65 due to a faulty television and quickly spread up to flat 79. This was a severe fire and spread into the corridor. This fire ignited the suspended ceiling which did contain a high fire load. There was a wall flames down the whole length of the corridor. The linings contributed to the fire spread due to the number of layers of paint. The fire spread into flat 81 due to the fire size in the corridor. Fire spread to lower flats 37 and 53 due to falling embers.
Fire Safety Features
The composite panels were in place at the lower third of the façade of the bedrooms and there were also present in the door between the flat and the balcony. The panel of a building required of a building of Lakanal’s size would expected to be of fire resistance to the old Class O system or the new European standard, in other words limited combustibility and surface spread of flame. They were actually found to be of class 3 when they were tested to BS476, clearly not acceptable.
The suspended ceiling posed serious risk to the occupants with a high fire load. This was a particularly low ceiling which caused another probl em as it only reached the top of the door. There was a lot of softwood boarding, insulation around the cables as well. The front doors of these flats were fire resisting but were missing smoke seals which not risk assessed to recommend any upgrade. These doors were very good in terms of fire spread but did allow a considerable amount of smoke to enter the door.
The staircases in the flats were originally located in the flats linking the lower and upper parts, however it did not breach the compartmentation. There was a compartment floor separating the staircase from the staircase. The problem is that when they lowered the ceiling in the corridor it caused problems with the staircases They had 2 choices, they could either shift the whole staircase over in the flat and sacrifice a couple of feet in the flat or they cut a hole in the compartment floor and compartment wall. They decided on the latter and this was an after thought not the original intention. This resulted in a combustible staircase cutting through the compartmentation. It was not clear what was put in to bring the compartmentation back into play but clearly not acceptable.
The walls offered about 60 minutes fire resistance. The problem is that they had to run services through the compartment walls such as the heating system, however, when you put a penetration through a wall you put in appropriate fire stopping to the same level as the wall. It was found that some of the fire stopping was good, some was patchy and some was totally incomplete. The pipes in the bathroom of flat 81 were particularly bad and allowed a significant amount of smoke into the bathroom.
It was identified that there were 13 layers of paint on the corridor walls which resulted in the linings not having adequate firer resistance and contributing to the fire spread.
This method of ventilation involves allowing air to enter at one end of a corridor and discharge at the other and was common when the building was first built. This method could have been maintained even though it is not very effective when there is not much wind. However, putting in security doors removed this technique and then by putting vents in them resulted in the worst of both methods. The occupants of flat 81 tried to stop smoke entering through the vent in the bathroom by using magazines and taped them up. However, it was not effective and in fact it started to burn the paper. The extraction system connected all the flats with a direct route from flat 53 to flat 81. This resulted in the deaths in the bathroom
4,15 fire started due to television flat 65 on 9th floor
4.16 fire alarm in flat 65 operates
Within 2 minutes of Fire Service arriving there was a flashover in the top floor. The flames were leaving the upper floor window and were burning the panels above to the bedroom in flat 79. The fact that there was a westerly wind didn’t help because the flames were being forced against the wall of the building towards the panels. These panels instantly ignite and within 4 ½ minutes they have burned through and allowed a flame to be introduced in flat 79 and ignited the contents. So we know have a fire on the 9th, 10th and 11th floor of the building.
The Fire Service set up a bridgehead on 7th floor
The Fire Service arrived at flat 65 very quickly and suppresses the fire.
Just over 30 minutes into the fire, we have fallen debris ignite flat 37 on 5th floor and flat 53 on 7th floor. We now have fires on the 5th, 7th, 9th 10th and 11th floor.
There was also a problem due to the grilles in the doors to the staircase allowing the smoke to enter into the staircase and the smoke was been drawn down to lower floors due to the negative pressure on the eastern side of the building. What they had was ground to floor smoke logging of the staircase. This was completely untenable for both residents and firefighters who were trying to maintain command and control at the bridgehead
At around 17.00 the decision was taken to move the bridgehead, their scene of forward operations.
17.02 Firefighters reached flat 53
They also sent a team to the 12th floor to carry out a snatch rescue.
17.22 The fire in flat 53 was dealt with.
17.30 The compartmentation in flat 81 is beginning to fail in particular the boxing in under the stairs. The corridor is out of action as is the internal staircase and therefore they are trapped in the bathroom
Lakanal house was considered the best that was available at the time it was built. It was a tragedy that we can learn from. We have learnt that cross ventilation is not effective. Over time buildings like this which have refurbishments carried out lose their initial compartmentation and fire safety strategy. There were a number of factors that led to their deaths and none in isolation was the cause. The information included in these notes is based on information provided to ourselves at various conferences and media coverage. They are to the best of our knowledge correct.