Independent expert Arnold Tarling's Fire Risk Assessment
Arnold Tarling, an independent Fire Safety Expert and Chartered Surveyor shares the report of his findings at the Ledbury Estate with Southwark Council and the residents:
LEDBURY TOWER BLOCKS – a brief inspection. Arnold E Tarling BSc FRICS MCIArb 1) Common parts a. The section of wall above the flat entrance doors is not fire proofed correctly i. In some areas I could see the internal plasterboard! The internal plasterboard does not appear to be fireline board or similar. ii. In other areas I could see the softwood stud framework iii. In some areas there is no fire protection behind the steel ducting iv. The Superlux (or similar board) is not secured with clout head nails or countersunk screws – they appear to be fixed with panel pins (just like Lakanal House and Marie Curie House) and these will fail rapidly. v. The chamfered edge of slabs passing above the doors are open in some areas and some have coaxial cable run through. Not fire stopped. vi. There is a metal pipe that runs through – the gap between the Superlux (or similar) and pipe is not fire proofed vii. To one flat a flexible plastic cable duct passes through the structure above the door but there is no fire stopping. viii. The wall above the door should be 1 hour rated – it isn’t. ix. The Fire Wardens are working 12 hour shifts, some were found to be asleep, others were missing from their positions / landings.
b. To one ground floor flat there was at there was a plastic vent to an air handling unit run through what should be a 1 hour rated wall / glazed screen. This has no fire damper. c. To every upper floor there are insulated infill panels to the PVCu frames at low level to the shared lobbies – there are similar panels to the windows to the flats hallway next to these. This design failed in 4 minutes at Lakanal House in 2009. The voids between the PVCu frames and structure is filled with flammable polyurethane expanding foam. d. PVC ducts installed on some floors – not opened up – are the cables restrained with metal brackets? e. SUGGEST Gerba locks to communal flat lobby doors – in my experience the drop release key fireman’s override fail and just spin round and round not doing anything. In addition these are at high level at the hottest point and may have failed in the heat or be obscured in the smoke. f. The STAY PUT signage should be overboarded with new instruction to GET OUT. 2) INTERNAL a. No fire stopping to junction of wall and slabs. b. No fire stopping between vertical wall junctions. c. Flammable compressible material used in vertical wall junctions including junctions between flats. d. Failed plaster to vertical junctions of walls due to movement – open joints to full depth of party walls. e. Holes between gas riser and slab – direct connection of kitchen to kitchen f. Concrete around the gas pipes is so poor that it breaks away in ones fingers g. Fire spread route from kitchen into living room and hallway via redundant heater cupboard.
LEDBURY TOWER BLOCKS – a brief inspection. Arnold E Tarling BSc FRICS MCIArb
3) APPRAISLS REQUIRED IN 1968 AND IN 1985 BRE DOCUMENT – fire stopping , gas, checking Type B joint a. Clearly not done or IF it has been done the recommendations have never been followed up. b. ARUP report has NOT checked the Type B Joint – tie bars to looped ends of panel rebar sometimes missing and rarely tied at mid-point. No concrete fill. Rebar normally at bottom acting as a pivot. c. It is not known whether the block can withstand the force of a 5PSI gas explosion. d. It is known that the blocks have never been 1 hour fire rated.
CONCLUSION The blocks have never been fit for habitation. The appropriate appraisals and inspections have never been undertaken or if they have been the findings have never been complied with. It is not known whether the properties would suffer progressive collapse or not in an explosion. Until it is proven that the Type B joints have been properly formed and that the structure is sufficiently strong to withstand a gas explosion then the gas supply should be disconnected. NOTE there have already been several leaks of gas in the block or underground adjacent to the blocks with the risk of penetration into the blocks following the service ducts and service pipes. I reported a severe leak last Sunday 9 th July with gas escaping through a Fire Hydrant and waited for the engineer from Morrisons to arrive. There is evidence in the pavements of other gas leaks and investigations. The national gas network should be approached to install new mains in this street. Full Level 4 Fire Risk Assessments are required to all areas. The Fire wardens should be put on 8 hour shifts and should have to report in regularly to show that they are awake and in situ. Every external wall junction and floor / ceiling junction will require fireproofing with a suitable material. Elastomeric linear joint seals may be appropriate, Nitrile PVC rubber may be appropriate, a rubberised bellows system may be required due to fact that the gaps only form in very hot weather and the insertion of the materials in cool weather will not work. In any even the kitchens and bathrooms will require stripping out and every room will be affected at ceiling and floor level. Due to the fact that the original design life for the TWA buildings was 60 years and the cost of carrying out the remedial work with people living in the property will be lengthy and extremely inconvenient full decanting should be considered. It may well be cheaper to demolish and rebuild to current standards. The services of a Quantity Surveyor should be sought. The provision of portable personal Mist system in the kitchens might be appropriate as this room is most likely to be the location of a domestic fire.