ᐅ Damp Basement

Hello

Unfortunately, the basement has damp walls. The cause is likely moisture entering from the outside. Therefore, a horizontal damp-proof course is probably the right solution here. Now I wanted to ask if anything can also be done regarding ventilation. At the moment, the basement is not equipped with any ventilation.

Thank you very much

Hello swissmaker,
You can generally assume that a modern basement has been waterproofed from the outside; if this waterproofing has a leak, the basement exterior wall will only become damp exactly at that spot.

If the walls are damp over a large area, condensation could be the cause. Is there an open connection between the ground floor and the basement, such as a staircase without a tightly closing door? In that case, the basement air could warm up and condense on the relatively cold basement walls.
A horizontal damp-proof course alone would not do much good if the basement exterior wall is not waterproofed; vertical waterproofing is required—completely sealing the exterior walls from the top down to the foundation.

But first, you should examine "How does the moisture appear?":
- all basement walls damp over a large area
- damp spotty in places
- only on the exterior walls
- on the exterior walls mainly in the floor area up to about 1.0m (3 ft 3 in) in height
- mainly at the floor/wall junction

I have to agree with Hertweck, moisture does not always mean that the horizontal damp-proof course is defective. However, it is almost always advisable to install a horizontal damp-proof course alongside the vertical waterproofing. It is often helpful to have an expert identify the causes and possible solutions. Although this involves upfront costs, they are usually well invested before taking the wrong measures.