One thing that undoubtedly puts off a prospective buyer is knowing that there is a possibility of water in the basement. Water seems to be a prevalent problem in homes, from timber rot, to leaking crawl spaces and basements to dripping ceilings. A wet basement is the second most common problem for home owners (the first being roof leaks!)

It is also bad for your health: extreme dampness in houses has been linked to respiratory illness and can have a severe affect on children and the elderly.

If your basement is currently suffering from too much water, it is better to fix the problem and remove the evidence of flooding before you put it on the market. It is also helpful to get a certificate to say it is water-proofed. If you only have damp proofing, this will not be enough to stop the water coming in. Damp proofing cannot deal with a flood of water, whereas water proofing will reject a flow of water.

But before any repairs take place, the cause will have to be found. A common problem that is simple to fix is a broken, or malfunctioning down spout. This is easy to spot, although if you just give it a quick look you may miss something. Sometimes there can be a blockage in the pipe that you cannot see (a bird's nest?) so pour water through it to check. The downspouts should not drain into any of your other systems and ideally, the water should be draining out at least five feet away from your property; this may require you to buy an extension for your downspout.

A more bothersome problem causing damp basements could be breakdown of the foundation drains (sometimes called weeping tiles). Some homes also have a pump which works with the weeping tiles, so check this too.

There is also the more obvious reason like a crack in your basement walls which allows water to seep through. These can be patched both from the inside and out. If they are fairly large cracks, use an expanding hydroscopic material (as it dries it will expand). If they are really large cracks, you may wish an engineer to check the structural soundness of your home.

Water in the basement is not usually a municipal problem, but you could check with the neighbors to see if they are experiencing the same trouble. If they are, and it is not the municipality, it may be the water table in your area. If you have a high water table then during every spring thaw and autumn rainfall your land will become drenched and soggy.

Often the water will seep into the basement because the ground outside is too high. This can happen if the building has 'settled' over the years, or if the wind has gradually banked soil against your home. Both these conditions may encourage rainfall from the earth to seep into your home and can be easily be remedied.

The solution is to lower the earth all the way around the house. It must also be lowered in a gradient sloping away from the house, so that it does not puddle and overflow. It needs to drain away from the house wall. The width of the lowered sloping land should be at least 24 inches in depth, although most contractors recommend 6 foot! The gradient should be about 6 inches as it slopes away into the yard.

If the problem is really severe, and every spring the rain raises your water table to flood levels, you can dig down further at the edge of the gradient, where it joins the lawn. Here you can make a little ditch to encourage even more drainage away from your walls, and perhaps let it run into an area near the street.

The house wall can then be sealed from the outside, as more of it will be exposed. There are several types of water-proofing applications to choose from and if you want a certificate you will have to employ a reputable company.

Finally, if it seems unavoidable to keep the water out, hire a contractor to put in a drainage system and a sump pump, and use a waterproof finish, like ceramic tiles, on your walls.