One indicator that your home has an issue with rising damp is that any signs of damage are confined to the bottom metre or so of your walls. Look for:
Warped and Rotten Skirting Boards
Damp, rotting or warped skirting boards are a classic sign of rising damp. Sometimes the damage will be subtle, and will come to your notice because the heads of nails in your skirting board appear rusty. Or you’ll spot the telltale round holes of woodworm, and perhaps notice the newly-pupated adult beetles crawling over the surface of the wood.
Wood rot can be another consequence of rising damp. Visit our timber infestation pages for more information on this potentially serious damp-related problem.
Discolouration of Interior Walls and Plasterwork
If your walls are papered, you may notice that the paper has peeled away at the bottom, near the skirting board. Try touching the wallpaper: if it feels as though there is something crunchy or granular behind it, you almost certainly have rising damp. This interesting texture is created by the moisture-attracting salts which are deposited when groundwater is wicked up inside your brickwork and then evaporates from the surface of the wall.
Because groundwater isn’t crystal clear like tap water, its presence usually leaves discolouration, too. In painted or plastered surfaces the damage caused by rising damp is usually more evident. You’ll often see plaster and paint crumbling away at the base of the wall, with a clear demarcation line about a metre from the floor.
Salty Tidemark on Exterior Walls
As water is drawn upward through the brickwork by capillary action, it must struggle against gravity. Depending on the particular characteristics of the wall concerned, gravity usually wins out at a height of between 1-1.5 metres, when the rise of moisture halts. A certain amount of evaporation then takes place at the interface between the wet and dry sections of wall: this gives rise to the classic salty tidemark which reliably indicates the presence of rising damp.
Below the tidemark, the wall will often be visibly damp or discoloured, and may have algae, moss or fungus growing on the affected areas. Cement and mortar tends to crumble away, and the fragments can be found piled at the junction of the wall and the ground, further compounding the damp problem.
Rising damp has potentially serious consequences for your home, so if you notice any of the signs described above, book your free damp survey now book an inspection. You can also call our rising damp experts on 0207 127 6886.