Serious house fires are tragic no matter what type of house they occur in but is the British Iron and Steel Federation House, more at risk than any other type of property?
Is a BISF house a fire risk by design?
Not according to a Building Research Establishment report, we take a closer look.
In the 70’s and 80’s a series of fires occurred in BISF houses that resulted in tragic loss of life. Fire and fumes spread quickly, trapping occupants who had just minutes to escape. Soon after suspicion followed.
Could the non-traditional building methods and materials used, be the cause of fire spreading so rapidly throughout the houses involved?
Was the very fabric of a British Iron and Steel Federation house a tinderbox in disguise?
During construction in the 1940’s, BISF houses were subjected to strict building guidelines.
- All internal wall and ceilings should be lined with plasterboard known for its fire resistant properties.
Severe post war material shortages meant that some of these specifications were soon modified. Plasterboard was prescribed for use throughout the ground floor, however:
- Hardboard panels could now be used to line first floor walls only.
- Wood fibreboard could be used to line first floor ceilings only.
Plasterboard offers better fire resistance over hardboard and fibreboard and was considered essential for ground floor use where the majority of house fires start.
Sadly however these guidelines were not followed in many cases.
- Hardboard and fibreboard was often used throughout construction and in some cases, NO plasterboard used at all.
In 1982 the Building Research Establishment carried out an investigation of actual fires in BISF houses.
Present in many homes where fire occurred was untreated polyurethane foam filled furniture, well-known for its rapid burn qualities and noxious fumes, containing hydrogen chloride & hydrogen cyanide.
The majority of fires also involved open doors which allowed for rapid fire spread but even when closed, the glass fanlight above internal doors soon cracked and broke under intense heat, allowing fire to enter other areas quickly.
It had long been thought that the hollow stud wall cavities of BISF houses facilitated the rapid spread of fire from the ground floor upward, into the first floor rooms.
The BRE studied six severe living room fires where plasterboard lined the walls of the ground floor. They noted that even when the wall surface and stud work had been breached by fire, no rapid or severe spread of fire was caused through the cavity space. In most cases the rapid spread of fire from the living room to the first floor was via the staircase through open doors or perished fanlights.
Five of the bedroom fires originated in or near to the fitted cupboards that separate the two larger bedrooms but the report did not state how these fires had started. It should also be remembered that cigarette smoking in bedrooms and living rooms was very common during this period and may have had some relevance.
The Roof Space & Ceilings
Overall the BISF roof contained fewer combustible materials in its construction than a traditional slate or tiled roof. However BISF houses fitted with original bitumen backed aluminium roofing sheets tended to suffer more than their asbestos roofed counterparts due to the ignition of the bitumen lining.
The roof space ignited during all living room fires due to fire entering the staircase and burning through the plywood loft hatch on the landing. (In some BISF properties the loft hatch is found in the rear bedroom which could also be vulnerable due to open door ways.)
The Fibreboard ceiling sheets on the landing failed rapidly allowing fire to enter the loft space, similar occurred during some of bedroom fires but the presence of fibreglass loft insulation reduced the severity of the spread upward. Other factors depended on the quantity of combustible items previously stored in the loft space.
Hardboard wall coverings did increase the spread of bedroom fires when the fire was present lower down in the room but the speed and impact reduced closer to ceiling level and once fire had broken through the ceilings fibre board. This was partly due to the fire ‘venting’ into the loft space and reducing its lateral spread below. Fire will travel towards the richest source of oxygen. When the fibreboard ceiling is breached, the loft space above provides a ready supply of oxygen allowing the fire to burn upward rather than outward in the oxygen starved room below.
The structural steel frame of the houses involved suffered very little damage and even in the most severe fires only slight distortion to steel ceiling and roof supports was found.
The BRE summarised that BISF houses do not appear to be significantly different to any other traditionally built brick house in either the hazards present or the form of construction used. It suggests that the greatest hazard found was from the types of furniture installed in the houses rather than the materials used in construction.
Good news for BISF home owners but certainly no need for complacency.
Technical Fire Safety Officer Simon Hill of Avon Fire Service explained how every year the Fire and Rescue Service is called to over 50,000 house fires, that’s around 140 a day! These fires kill around 500 people and injure over 11,000 more.
“Many of these deaths could be prevented if people had an early warning from correctly fitted smoke alarms, enabling people to get out of the house in time. Just one or two minutes of extra time given from a smoke alarm can mean the difference between life and death” explained Simon.
Even more astonishing was the fact that you are TWICE as likely to die in a house fire where no smoke alarm is fitted! With smoke alarms starting at just £5, this really is a very small price to pay for saving you life and with new designs having 5 and 10 year batteries you never need to change it makes even more sense.
Avon Fire Service offer home fire safety visits to many people at risk from fire in the home, from families with young children to older people living alone. Steve explains “The first part of a Home Fire Safety Visit process involves a telephone assessment, so we can work out your level of risk and takes into consideration factors concerning your property and the people who live there. Following the assessment we will provide you with fire safety advice and may visit your property to make recommendations specific to your home. We may also fit smoke alarms in certain situations and especially if you are elderly, vulnerable or have problems if needed and all of these services are provided free of charge.
To find out more simply visit AvonFire for more information and access to the on-line application.