Damp walls are a familiar sight in Lahore: a dark band near the floor, white salt powder (efflorescence) pushing paint off, plaster that crumbles, or patches that spread after rain. Painting over it never lasts, because the water is still coming. Treatment works only when the cause is found and dealt with.
Common causes
| Type of damp | What it looks like | Typical cause |
|---|---|---|
| Rising damp | Damp band and salt marks along the lower part of ground-floor walls | Missing or failed damp-proof course (DPC); ground or courtyard level higher than the inside floor |
| Rain penetration | Patches on external walls that grow after rain | Cracked plaster, open joints, failed parapet or window sills, poor drainage from roof or balcony |
| Plumbing leak | Damp spot that stays wet in all weather, often near bathrooms or kitchens | Leaking supply or drain pipe inside the wall |
| Tank or drain leak | Damp next to an underground tank or drain line | Cracked tank wall or broken drain |
| Condensation | Moisture and mould in cold, poorly ventilated rooms | Humidity and lack of ventilation, not a leak |
What's included
| Scope item | What it involves |
|---|---|
| Inspection | Checking the damp pattern, outside ground levels, pipes, drains, tanks and external walls |
| Removing damaged plaster | Hacking off salt-damaged plaster to a height beyond the damp area |
| DPC treatment | Chemical injection or other damp-proof treatment at the base of walls (for rising damp) |
| External wall waterproofing | Crack repair and water-repellent or waterproof coating on outer walls |
| Pipe or tank repair | Fixing the leak at its source |
| Re-plastering | Plaster suited to damp-affected walls, allowed to dry before paint |
| Finishing | Breathable or damp-tolerant paint as specified |
When you need it
- Paint peels or bubbles and white powder appears on walls.
- Plaster sounds hollow or crumbles near the floor.
- Damp patches spread after rain.
- Rooms smell musty, or furniture against walls gets mould.
Step-by-step process
- Map the damp. Note where, how high and when it appears.
- Check outside. Compare outside ground or courtyard level with the inside floor; check drains, gutters and the base of external walls.
- Rule out pipes and tanks. Pressure-test supply lines and inspect tanks near the wall.
- Diagnose and propose. The contractor explains the cause and the treatment in writing.
- Fix the source. Repair pipes, improve drainage, lower outside levels where possible, or treat external walls.
- Treat rising damp where needed, using the specified DPC method.
- Remove and replace plaster in the affected zone.
- Allow drying. Walls need time to dry before painting; rushing this brings damp back.
- Finish and monitor through at least one rainy spell before final payment where possible.
Approvals and documents
Treating damp inside your own home is maintenance and does not usually need approval. If the cause is a shared wall, a neighbour's drain or a society water line, report it in writing to your neighbour or society. In apartments, external walls are often managed by the building.
What affects the cost
Wall damp treatment is usually priced per running foot or per square foot of treated wall, sometimes as a lump sum per room. We do not quote rates; get written quotes. Factors:
- Cause — a pipe repair costs very differently from DPC treatment along many walls.
- Length and height of affected wall.
- Plaster removal and debris disposal.
- DPC method used.
- External wall work — scaffolding or ladders for upper floors.
- Finishing — plaster type and paint.
- Furniture and fitted items that need moving.
Questions to ask the contractor
- What type of damp is this, and how did you decide?
- Have you checked pipes, tanks and outside ground levels?
- How high will you remove plaster, and why?
- What DPC or wall treatment will you use?
- How long must the wall dry before painting?
- What will you do if the damp returns? Is that in the written warranty?
Red flags
- Recommending paint or wallpaper as the fix.
- Treating rising damp without checking for a pipe leak.
- Re-plastering immediately on wet walls.
- Same treatment proposed for every wall regardless of cause.
- No written scope or warranty.
FAQs
Why does deewar ki seelan come back after painting? Because paint does not stop water. Salts carried by the water push the paint off. The source must be fixed and the wall allowed to dry.
What is a damp-proof course? A barrier near the base of a wall that stops ground moisture rising. Many older houses have none or one that has failed, and some have had it bridged by raised outside floors.
Can I treat damp from inside only? For rising damp and pipe leaks, yes. For rain penetration, the outer wall needs attention too.
How long does a wall take to dry? It depends on wall thickness, season and how wet it was. Ask the contractor for their recommended drying period before paint.
Is mould on walls the same as damp? Mould often comes with damp or with condensation. Find which it is: condensation needs ventilation, not waterproofing.
Sources
This page gives general practical guidance and does not quote rates or standards. Get written quotes after inspection.