What does rising damp look like?
Rising damp usually shows as a band of damp, stained wall from floor level up to around one metre, often with a tide mark along the top. Within that band you may see white salt deposits, bubbling or peeling paint and crumbling plaster, and the room may smell musty.
1Damp Patches at the Bottom of the Wall
Rising damp typically affects the lower sections of walls because the moisture originates from the ground.
The affected area may appear darker or visibly damp compared with the surrounding wall, usually rising up to around one metre above floor level, with a visible “tide mark” where the damp band ends.
2Peeling or Bubbling Paint
Moisture within the wall can cause paint, wallpaper and other finishes to bubble, blister, flake, peel or come loose.
If the moisture source remains, repainting the wall will usually not provide a lasting solution. We explain why in why paint keeps peeling on the same wall.
3White Salt Deposits
White or powdery deposits on the wall are often caused by salts carried through the masonry by moisture.
These deposits, known as efflorescence, can become particularly noticeable as the wall dries and moisture evaporates. See what causes salt on walls.
4Crumbling or Damaged Plaster
Persistent moisture and salt contamination can cause plaster to become loose, powdery, cracked or crumbly.
Heavily contaminated plaster may need to be removed as part of the remedial process.
5Damp Staining and Discolouration
Affected walls may develop dark, brownish or yellowish staining.
The pattern and location of the staining can provide useful clues when investigating the source of dampness.
6A Musty or Damp Smell
Rooms with damp walls often smell musty or stale, especially when windows and doors have been kept closed.
Persistent moisture in the wall raises the humidity of the room and can encourage mould on nearby surfaces and furnishings, which adds to the smell.
7The Problem Keeps Coming Back
One of the clearest reasons to investigate further is when the same symptoms return after painting, replastering or other surface repairs.
If the moisture pathway has not been addressed, the wall may continue to deteriorate.
A Simple Homeowner Checklist
- Is the dampness mainly near the bottom?
- Is the paint peeling or bubbling?
- Are there white salt deposits?
- Is the plaster crumbling or deteriorating?
- Is there visible staining or discolouration?
- Is there a musty or damp smell in the room?
- Does the problem keep returning after repairs?
If several of these signs are present, the wall should be properly assessed.
Signs Are Not the Same as Diagnosis
These symptoms can also occur with penetrating damp, condensation, plumbing leaks and other moisture problems.
The important question is not only "what does the wall look like?" but also "where is the moisture coming from?" Correctly identifying the cause is the first step towards choosing the right treatment.
Seen the Signs? What to Do Next
Start by confirming the cause. Our guide to rising damp vs. penetrating damp explains how to tell the most common causes apart, and how rising damp occurs shows what is happening inside the wall. If you are still unsure, you can book a survey and assessment.
Common Questions
How high does rising damp go?
Rising damp usually affects the lower part of the wall, typically up to around one metre above floor level. The exact height depends on the wall, how wet the ground is and how quickly moisture can evaporate from the surface. Damp that appears much higher up is more likely to have another cause, such as a leak or rain penetration.
Can rising damp affect internal walls?
Yes. Internal walls built off the ground floor or foundations can draw up ground moisture just like external walls, particularly where there is no effective damp-proof course.
Does rising damp smell?
Damp walls often make a room smell musty, especially when it is closed up. The smell is a useful clue, but it does not on its own show where the moisture is coming from.
Recognise the signs. Find the cause. Stop rising damp. Restore your walls.