Short answer
On interior walls, damp can come from condensation (air that is too humid) or from the building itself (rising damp, infiltration, water damage). The location of the signs helps orient the diagnosis, but a full diagnosis is needed to confirm.
Two main families to distinguish
Moisture on an interior wall can come from ambient air condensing on cold surfaces, or from water present in the wall itself.
Distinguishing these two families is the first step: they do not call for the same response.
Observe where the signs appear
The height and location of the marks are valuable clues.
The same home can combine several causes, which makes observation all the more useful.
- High walls, corners, behind furniture -> possible condensation
- Base of walls, damp band, salt deposits -> possible rising damp
- Localized mark near an opening -> possible infiltration
- Appearance after a leak -> possible water damage
Do the marks keep coming back despite cleaning?
That is often a sign that the cause needs analysing, not just the surface.
What is better to avoid
Repainting, applying a wall covering, or using a so-called anti-damp product without understanding the origin can hide the problem and delay diagnosis.
The marks are likely to reappear as long as the cause is not treated.
How MURSAIN proceeds
MURSAIN starts with an analysis of the causes: rising damp, condensation, water damage, or a combination of phenomena.
The appropriate solution (rising damp treatment, air treatment, drying) is then proposed according to the diagnosis.
Frequently asked questions
How can I tell whether my interior walls suffer from condensation or rising damp?
The location of the signs helps: condensation appears more often high up and in corners, while rising damp appears more often at the base of the wall. The diagnosis confirms it.
Does anti-damp paint solve the problem?
It can hide an effect, but it does not treat the cause. If the wall is still receiving water, the damage can return.