On the Level: Why Keeping Doors Shut Is a Burning Issue

In particular, fire safety regulations in buildings greatly depend on the fire service arriving to extinguish the flames within minutes of the alarm being raised. Hence, walls and floors separating dwellings are required to withstand a fire only for an hour before burning through, and internal walls and doors within homes need have only a half-hour fire resistance.

Unfortunately, the fire integrity of internal doors is often meaningless, since most people cannot be bothered to close them anyway. And yet shutting the door is one of the most effective fire precautions we can take. A closed door not only stops flames and smoke from spreading to other rooms, but it also deprives a fire of vital oxygen - meaning that it smoulders rather than roars, thus providing time for the occupants to escape and the fire to be brought under control.

The habit of leaving doors open is an unfortunate side effect of central heating. When rooms were individually heated by coal fires, there was a natural instinct to close the door, to keep the heat in and the draught out. But now that homes are kept at a uniformly high temperature throughout, many people regard doors only as obstacles to their progress from one room to another, and leave them permanently open.

The Building Regulations attempt to overcome this by requiring internal doors to be self-closing in certain situations. One such is when a two-storey house is converted to three storeys by the addition of a loft conversion; the downstairs rooms have to have self-closing doors to contain a fire and protect the escape route from the loft. A similar situation prevails when a house of three or more storeys is converted into flats.

20 November 2002: On the level: things they don't tell first-time buyers [Jeff Howell on spare boiler parts] Developers and contractors often comply with this regulation by fitting internal doors with Perco door closers. The Perco is an ingenious device which contains a strong spring inside a cylinder, which is mounted in a hole drilled into the door, with a chain attaching the spring to the door jamb. The Perco is simple, unobtrusive and cheap, and it does a very effective job of closing doors.

Sadly, these qualities are often not appreciated by occupants and neighbours, since the Perco's simple spring action causes an open door to accelerate until it reaches a closed position. Or, to put it another way, it slams shut.

Householders often get around this problem by propping the door permanently open using a rubber wedge or a suitably robust ornament - antique flat irons being especially popular. But whatever, the result is no self-closing door, and no fire protection. (The equivalent situation in offices is the fire door propped open with a fire extinguisher - well, there's always one handy, isn't there?) I suppose the real problem is that, until you've experienced a house fire, you never think it will happen to you. So fire safety precautions can seem to be a stupid inconvenience. Why on earth don't they teach children about this stuff at school?

Boiler sales ruse With reference to a recent reader's letter about boiler spares (November 17) , I subscribe to the British Gas Three Star Service, and I have also had a letter saying that the manufacturer has stopped making the spare parts and I should consider replacing my boiler with a newer model.

However, my boiler, a Worcester 24CDi, was installed barely a year ago - by British Gas. When I contacted the company to question it about the ethics of installing a new boiler at a time when it must have been aware of the spare parts situation, I was told that the warning was an unrestricted circulation to all their Three Star customers and that I could ignore it. My request for this to be confirmed in writing has been ignored.

MP, London Jeff replies I have checked with the manufacturers and they confirm that your model of boiler is still in production, and that parts will be available for the foreseeable future. This seems to be another example of questionable sales tactics by British Gas. If any other readers have received a similar letter, saying that some or all of the spare parts for their boilers are no longer available, and they send me a copy, I will check whether this really is the case.

Tilting window fault I live in a block of flats where PVC-U tilt-and-turn double-glazed windows are being installed. I was surprised to be told by the installers that only the tilting function of the windows is for ventilation; the normal side-opening function is intended purely for the purpose of cleaning. Should the windows be opened on the side hinges for any length of time, they say, this will result in sagging of the frames. Is this a normal characteristic of tilt-and-turn windows in the UK? I have lived in Germany with tilt-and-turn windows and always known them to be capable of normal opening on the side hinges, with double or even triple glazing.

PM, East Sussex Jeff replies Any window sold as tilt-and-turn should be capable of performing equally well in either mode. If the installers are warning that their windows will distort if opened on the side hinges then this is an admission that the windows are not fit for purpose (as defined by the Sale of Goods Act). The installers will doubtless be using very thin PVC-U with inadequate internal reinforcement, and the windows will have a limited lifespan. For independent advice contact Fenestration Associates (01676 523583; www.fenestrationassociates.com Wet floors in new home We are buying a new house on a development being built under NHBC control. The first-floor joists and waxed chipboard flooring were installed seven weeks ago, but the roof is still not on. It has since rained frequently, and water has soaked through the joints between the chipboard sheets, despite their being sealed with tape. I am worried that after the plasterboard ceilings are fixed, moisture will be trapped in the joists, causing them to rot. Should I insist that the plasterboard is not fixed until the floors have thoroughly dried?

DW, Plymouth Jeff replies It is acknowledged bad practice to install timber floors before a house is weathertight. The type of chipboard you describe is only moisture-resistant (for bathroom floors), not waterproof. The chipboard is likely to be damaged by the soaking, and the joists will move and shrink as they dry, causing cracking in the plasterboard ceilings.

You should engage a chartered building surveyor to monitor the situation and advise you on any legal problems likely to arise.