Make your home happy with our quick guide to keeping it damp-free this winter
As we enter the latter part of the year, the problems with damp experienced by our homes can become more pronounced. Here’s our quick guide to the different types of damp that can affect your property, how to spot tell-tale signs, and what can be done to remedy the problem. There are three main types of damp that can affect your home:
1. Rising Damp
Rising damp affects basement and ground floor rooms and is caused when part of the waterproof damp course material fails or if there is debris creating a bridge between the inner and outer leaf of the cavity wall. In properties without a damp-proof course, it is caused by capillary action drawing groundwater up through the fabric of the building. This type of damp can rise considerably above ground level and if left untreated can cause bricks to crumble and wallpaper to lift.
Symptoms to look out for:
• A tide mark low down on walls
• Soft, white, salt deposits on affected areas, which can also appear above the level of the tide mark
• Black spots of mould
• Decaying timber, such as skirting boards, floorboards and floor joists
• Staining of wall coverings, peeling wallpaper and blistering paint
Ways to treat it:
Simply painting over or repointing affected areas may only exacerbate the problem. The only way to solve the problem of rising damp is to either have a damp-proof course or damp-proof membrane installed or to have your existing one repaired. Dehumidifiers can also be effective in drying out the affected rooms but are not a cure.
2. Penetrating Damp (Lateral Damp)
Although penetrating damp can affect all levels of your property, if the signs of dampness are visible more than 1.2 metres above ground level it is likely that your property is being affected by penetrating damp rather than rising damp. This is caused by water ingress through a defect in the building, such as a leaking gutter or cracked rendering, or when an area of the fabric of the building has degraded to the point where it has become porous. The effects of penetrating damp are usually more noticeable after heavy rain.
Symptoms to look out for:
• Localised patches of damp staining on external walls
• Damp patches on walls or ceilings which may also show signs of salt deposits
• Plaster that is damp to the touch or is crumbling
• Spores of black mould that are isolated to one area
• Drips and puddles
Ways to treat it:
Once the root cause of the problem has been found and repaired, walls need to be given time to dry out naturally. This can be a slow process, especially if the area affected is quite large. Chemical water repellent can be applied to the walls to stop damp returning and in especially severe cases where the stonework and mortar has become so porous that damp is affecting the interior of the property, installation of a damp-proof membrane may be necessary.
3. Condensation
This is by far the most common cause of damp within the home and is caused when moist, warm air condenses on cooler walls or windows. Rooms which naturally generate a lot of moisture, such as kitchens and bathrooms, are most affected and the problem can become more pronounced during the winter months. Drying laundry indoors can also exacerbate the problem. Left untreated, condensation can damage paint and plasterwork and cause window frames to decay.
Symptoms to look out for:
• Droplets of water on walls and windows and puddles of water on windowsills
• Black mould growth, particularly on glass or around window frames
• An unpleasant mouldy odour
Ways to treat it:
The best way to treat condensation is to ensure your home is well ventilated at all times, allowing the warm, damp air to be dispersed outside and not settle on walls and windows. This is especially important during winter months when your home should also be kept relatively warm to avoid large variations in temperature.
Ventilation fans in kitchens and bathrooms are also very effective in combatting condensation, as are dehumidifiers in rooms that are particularly badly affected. Drying your laundry outside where possible will also help to keep your home free from condensation, but if this isn’t possible, ensuring they are hung on a clothes airer in a well-ventilated room will keep the problem to a minimum.
Conclusion
Knowing the signs of damp to look for and taking quick remedial action as soon as you spot any of the symptoms can prevent serious damage to your home and help keep repair costs to a minimum.