Damp is a common problem in basements when water seeps through the brickwork and into the internal areas. It can also impact the whole building as the damp spreads and so too do conditions such as black mould – which can cause poor health and respiratory problems for people living in the property. That’s why it is important to locate leaks and any other causes of damp in your basement and deal with them before worse problems follow.
Look for signs of dampproof
The first things to look for are obvious very wet areas and signs of humidity. Mould or mildew are both common in spots where there is a higher amount of moisture and are a key indicator of a damp problem. They are commonly found on walls but also on furniture, any paper in the room and even under flooring. Black mould is the most common type associated with damp but there are other kinds. It is important to find all of the mould and mildew before starting to take action.
Another thing to check is the smell of the basement. That musty, damp smell we all recognise is due to the presence of moisture and often of mould and mildew and is a sure sign there’s a damp problem lurking somewhere in the basement. The stronger the smell, the nearer you are to the source. And often mould of fungus grows around the leak or weak spot, so the smell of mushrooms often indicates where the problem is worst.
Finding hidden leaks
Sometimes, finding leaks or sources of damp can be difficult but there are still ways to track down the source of the problem. Efflorescence is a chalky, white residue that is produced by heavy moisture penetrating the walls. If you find it on your walls, it is a sure sign there is a leak or source of water in that area.
Discolouration of the walls is another indicator. When water seeps into the basement and evaporates, it leaves discolourations and stains on the walls, sometimes known as tide marks. Salt can also be left behind that causes a stain on the walls. So any signs that some parts of the walls are different colours to the others can indicate there is a damp issue.
Check wood and metal items
While walls, flooring and things like soft furnishings or paper are obvious candidates for the signs of damp, don’t discount checking around wood or metal items. Rusting metal nails or rotting wood can be signs of a damp problem just the same as marks on the walls. And these can be a useful way to isolate where the problem is worst.
Leak or seepage?
If you find signs of damp but you don’t find a leak, then the problem may be seepage. This is a natural process where porous materials like bricks absorb water and then deposit them into the basement. Normally, there will be measures in place to stop this – a damp proof course is one that protects above-ground areas of the house. But basements don’t always have these measures, or they may fail over time.
So if there is no sign of a leak, it might be worth having a damp proof expert take a look at the basement to see if the problem could be related to seepage and what is the best course of action to deal with it. There are different options including tanking the wall – covering them with special paint – as well as adding damp proof membranes and drainage channels. They will be able to look at the symptoms of the problem and find the right solution.
You may also find our infographic on Questions to Ask a Company about Basement Waterproofing useful too.