Go to http://www.askjeff.co.uk/ and check out his views on rising damp - he claims, quite reasonably, that rising damp is largely a myth. He maintains that specialist firms who offer a free-survey will always find dampness that may only be cured with their expensive programme of treatment.
In his book he mentions the Public Health act of 1875 that required a damp course to stop infected water leaching into dwellings. He claims that Holland, much of which is below sea-level does not require damp courses?
Howell suggests that dampness in walls has a cause such as leaking guttering or the outside ground-level being too high.
Look under the floorbaords - if there's damp soil then check that the air-bricks are not blocked - when it rains it's normal for the ground to become wet - the under-floor void needs a through-draught.
Find the source of the damp - fix it and provide adequate heating and ventilation to stop condensation and allow existing dampness to dry out. Then decorate. Good luck.
Richard Buxton, September 2008
