Strategies to combat damp problems

There are a number of simple but effective remedies for condensation. Open windows when the weather is suitable so that drier air can get in.

Fit extractor fans with humidity detectors in kitchens and bathrooms to remove moist air automatically, or else plug in a dehumidifier. Lastly, remember that sealing up doors, windows and unused flues to eliminate draughts will increase the likelihood of condensation.

Installing a damp-proof course (DPC) in an older house usually involves drilling holes into the second or third course of brickwork above outdoor ground level, then pumping a chemical waterproofer into the walls. You can hire the equipment and do the job yourself if you don’t need the guarantee.

Create less moisture by drying clothes outdoors whenever possible. If you have a tumble drier, vent it to the outside. Keep lids on boiling saucepans and shut bathroom and kitchen doors to stop steam spreading through the house. Use dehumidifiers in damp, enclosed areas and avoid heaters that run on paraffin or oil—both fuels produce large quantities of water vapour when they are burned.

If your home needs a DPC, schedule it into the order of work as early as possible.

The plaster on damp walls will have absorbed salts from the masonry and will have to be hacked off to a height of about 1 m (3 ft 3 in) before the DPC is installed. Then the masonry will need to be left bare for several months so that it can dry out before the walls are recovered—either with a traditional sand and cement plaster, or with one recommended by the damp-proofing Chichester company.

Always seek advice about the best way to tackle rising damp in a solid floor, which is caused by the absence or failure of a damp-proof membrane (DPM) between the floor and the ground beneath.

Low levels of damp can be tackled by coating the floor with a heavy-duty damp-proofng liquid to create a new DPM, then applying a thin sand and cement screed on top.

If you cannot afford to raise the floor level much, you can lay a self-levelling compound instead of a traditional screed to provide a new floor surface.

If, however, the damp problem is very severe, you may be advised to have the whole floor lifted and replaced.

Decorate kitchens and bathrooms with paint specially made for these rooms. Ordinary emulsion paint will flake or develop mould if it gets damp frequently, but anti-condensation paint is designed to absorb moisture from damp air and release it back into the atmosphere when the air is drier.

If condensation is severe, on north facing walls, for example, have them replastered with an anti-condensation plaster. Like kitchen and bathroom paint, this product absorbs moisture when the atmosphere is damp and releases it when it is dry. The plaster also contains small air bubbles which insulate the surface, helping to further reduce the risk of condensation.

First, you can hold condensation at bay by spending more on keeping the house warm—turning up the central heating and improving the insulation. Often, however, marginal adjustments—slightly more ventilation combined with a low but constant level of background heat—are just as effective, and cheaper.