Controlling damp is fast becoming part of everyday life for millions of people in the UK. Finding a patch on the wall or having a surveyor report come back stating the worst can be a huge worry for homeowners and tenants.
But don’t panic – there are different types of damp and some are relatively simple and cheap to fix. For the bigger jobs, though, it’s money well spent, especially if you consider that your health could be at risk. The World Health Organization has identified damp as a serious concern, as it can exacerbate asthma and cause other respiratory symptoms.
The causes of damp can be broken down into three main categories: penetrating damp, rising damp and damp caused by condensation.
A damp proofing professional should swiftly be able to identify which one is causing your particular problem and help you fix it.
This type of damp affects a lot of buildings and may look harmless, but can lead to wet rot, damp plasterwork, increased heat loss, musty smells, frost damage in the masonry and unsightly water damage on both the inside and outside of a property. It’s caused by a problem with the building or plumbing that has allowed water to leak into the home. This could be the result of cracked masonry, defective pointing, damaged water management systems, broken gutters, defective plumbing or split pipes. It could even be the result of an increase in the ground level around the outside walls of your property. Bearing in mind that water works its way to a weak point and then emerges rapidly from there, the cause of the problem could be several feet away from the damp patch. The solution could be as simple as opening up an air brick that’s been covered up accidentally, restricting air flow and causing moisture to become trapped. But the problem could be something else entirely. To confirm the presence of penetrating damp, you should get a survey of your property to ensure the correct identification.
HOW TO IDENTIFY IT
These are symptoms of penetrating damp:
- Watermarks that appear on the masonry and then grow larger if the water continues to enter
- Damaged plaster
- Random damp patches on walls, which do not dry out and move horizontally
- Drips and puddles
- Black mould growth
- Unpleasant musty smells
- Damaged timber as a result of being saturated by damp – this could possibly cause wet rot if left untreated.
This is the most complex type of damp to deal with. It can be caused by a faulty, or non-existent, damp proof course in your external walls, or by leaking pipes at the base of the wall. Even a previous damp problem that has caused water to pool at the bottom of the wall can cause it. If this is the case, you’ll definitely need your damp proof course repaired.
HOW TO IDENTIFY IT
Rising damp is often misidentified, so it’s important to know the common signs. These include:
- Decayed skirting boards
- Crumbling plasterwork
- Discolouration on walls
- Salt-stained plasterwork
- Decayed timber floors
- Peeling paint and wallpaper.
GET IT FIXED
Finding the source of the problem is the first thing to do. Start by checking your gutters and downpipes for leaks or cracks.
Examine the roof – including the pointing (gaps between tiles) and flashing (where a roof meets the wall of a chimney). Look at window frames and doors to see if there are any gaps from not being fitted properly.
You may need to call in a surveyor, with a certificated surveyor in remedial treatment (CSRT) qualification, to carry out the assessment and identify the cause of the problem.
Once you’ve found the cause, you’ll probably need to contact a builder or damp specialist to repair the fault. The solution depends on how the water is entering the building and the options available for stopping it.
In some cases, you may need damp proofing to stop it happening again, particularly if the external ground level is the cause or if you have a basement.
In the case of the latter, your damp proofing contractor may decide you need a cementitious tanking, which is a system that seals the inside of the basement with cement, preventing damp from penetrating your walls from the earth outside.
CONDENSATION – time to get tough
This is one of the most common causes of dampness in homes. It is the process by which water vapour in the air is changed into liquid water.
The air in a house can have a high level of water vapour, or humidity, due to the activities
of the occupants, such as cooking and drying clothes.
When this air comes into contact with cold surfaces, such as windows and walls, it condenses, causing water to be deposited. This can lead to areas of damp and promote the growth of mould.
Condensation can be greatly reduced by keeping the property well ventilated – making sure kitchen and bathroom windows are open as often as possible helps.
Also, installing extractor fans – one upstairs and one downstairs – will help to rid the air of excess humidity.