Jeff Howell: why are our windows so draughty? A: I make it a point never to intervene in marital disputes. But I can offer advice about general building principles. Homes converted from old farm buildings often seem to present problems for their owners. In your case you appear to have retained some original rough oak framing, and had softwood windows made and fitted into it. The oak framing itself will probably be leaking air at all the joints since, being a farm shed or stable, it was never designed to be airtight or habitable in the first place. And now the differential movement characteristics between the oak and the softwood are likely to have opened up gaps around the new windows as well. You state a couple of times that the windows are of poor quality, and I think you have probably answered your own question. Efficient draught-proofing is the single most cost-effective measure that any home owner can take to improve comfort and reduce heating bills, and I suggest you apply yourselves to this task before next winter. I am also confused about whether you intend to install a wood-chip boiler or a log burner - or are you planning to have both? All solid-fuel-burning appliances need an efficient supply of air for the combustion process, but none of them needs a "draught." An experienced HETAS-registered heating engineer will be able to advise on the best way of providing a draught-free air supply to whichever type of heating appliance you install. Damp annoying Q: A couple of years ago we had plastic soffits fitted to the front and back of the house. Since then there have been damp patches on bedroom walls near the ceiling - at soffit height. I had a builder in to check things, but he could not find any leaks. Is it condensation in the loft? The soffits have no holes in them, unlike the previous wood ones. Any ideas where the damp might be coming from, and how to solve the problem? SD, Sandhurst A: A PVC-U roofline products (fascias, soffits, bargeboards) are often fitted by unskilled workers who have no idea about the need for ventilation to keep condensation in check. While you do not mention it, I'm guessing that you might also have installed a thick layer of loft insulation above your bedroom ceilings. This will be keeping the roof space cool (by keeping more heat in the rooms below) and, unless a vapour barrier was fitted as part of the insulation process, the result will be warm moist air from within the house percolating into the loft and condensing out as liquid moisture on cold surfaces. Soffit ventilation is designed to help deal with this, and if your new PVC-U soffits do not have ventilation slots, then this could well explain the damp patches. You might be able to cut some holes in the new soffit material and fit circular vents, and see if this solves the problem. Send your questions to Jeff at Life, The Sunday Telegraph, 111 Buckingham Palace Road, London SW1W 0DT, email askjeff@telegraph.co.uk. Also visit Ask Jeff