In short, rising damp on interior walls is a build up of internal moisture. This moisture shows through the plaster and paintwork. When the problem gets more severe, it shows up as wet patches on your wall. The building industry is booming worldwide. But many contractors take short cuts and don’t ensure proper foundations. There are also lots of old houses, so the rising damp home owners see is subtle, but fairly common.
Is your wall or foundation compromised for some or other reason? It may be because your home was built a long time ago. It may also have been built in a less-than-adequate manner by an amateur contractor. Whatever the reason, rising damp happens all the time. Some of the worst cases of rising damp has ever seen occur because of water that travels up from the ground and into your wall. When this happens, no amount of paint can hide the problem for long.
Moisture in your wall is likely to have a snowball effect of damage. It spreads slowly throughout your entire wall and will eventually affect other areas of your home. You can try and paint over it, but eventually it will show through. There are really only two ways to treat this issue: You could strip your entire wall and replace the DPC, or you could use Damp-Vent supplied plugs and air the moisture out of your walls. Which one sounds easier—and cheaper—to you?