Damp is one of those defects that can be easy to see but much harder to diagnose properly.
A stained wall, cracked plaster or peeling paint may show where moisture is appearing, but not necessarily where it is coming from. Water can track through masonry, around openings and along junctions before becoming visible internally.
That is why a proper defect analysis should focus on the source of the moisture, the route it is taking and the order in which repairs should be carried out.
At Stokemont, our Defect Analysis inspections are designed to get behind the visible symptom and establish what is actually causing the problem.
Start With the Pattern
The position and distribution of damp can provide useful clues. Moisture around a bay window, external wall, chimney breast or window reveal may point towards penetrating damp, defective rainwater goods, failed pointing or deteriorated external finishes.
Damp at low level may suggest something different. The important point is that damp should not be diagnosed from one stain or one meter reading alone. The internal symptoms need to be considered alongside the building externally.
Moisture Testing Helps Build the Picture
Moisture meters can be useful for comparing affected and unaffected areas.
For example, a dry section of wall may return relatively low readings, while the visibly affected area records notably higher moisture levels.
This can help define the extent of the problem, but readings should always be interpreted alongside the condition of the wall, plaster, finishes and external building fabric.
A moisture meter is a useful diagnostic tool, not a diagnosis in itself.
Look Outside as Well as Inside
One of the most important parts of diagnosing damp is checking what is happening externally.
Defective gutters, leaking downpipes, failed joints, damaged brickwork and poor pointing can all repeatedly wet an external wall.
Over time, that moisture can penetrate internally and lead to:
- staining;
- cracked or hollow plaster;
- peeling decoration;
- salt deposits;
- moss growth;
- spalled brickwork; and
- deterioration of mortar joints.
The visible internal defect may therefore be only the end result of a problem higher up or further along the elevation.
Why Plaster Cracks and Debonds
Repeated dampness can cause plaster to lose adhesion with the wall behind it. This often results in cracking, bulging or a hollow sound when the area is lightly tapped.
At that point, simply filling the crack is unlikely to provide a lasting repair. If the source of moisture remains active, the defect will often return.
Repair the Cause First
This is the most important part of any damp repair. If the problem is being caused by defective guttering, a leaking downpipe or failed external masonry, that defect should be resolved first.
Once the source has been repaired and the wall has had sufficient time to dry, internal repairs can then follow.
These may include:
- repointing;
- repairing damaged brickwork;
- making good external finishes;
- removing loose or debonded plaster;
- replastering; and
- redecoration.
The sequence matters. Repairing the internal finishes before stopping the moisture can simply hide the problem temporarily.
Damp Does Not Always Appear Where It Enters
Water can travel through the building fabric before becoming visible. That is why the source may be above, beside or even some distance from the stained area.
A proper assessment looks for a logical relationship between the internal symptoms and the external defect.
The strongest diagnosis usually comes from several pieces of evidence pointing in the same direction rather than one isolated observation.
When Should You Instruct a Defect Analysis Report?
A targeted Defect Analysis Report can be useful where:
- damp keeps returning after decoration;
- plaster is cracked, loose or hollow;
- there is staining around windows or external walls;
- moisture readings are elevated;
- rainwater goods appear defective; or
- the source of the damp is unclear.
The aim is to establish the likely cause, identify what should be repaired first and set out a sensible remedial approach.
At Stokemont, our Surveyors undertake Defect Analysis inspections across London and the surrounding areas, helping property owners move from the visible symptom to the underlying cause.
Get an Instant Quote
If you are concerned about damp within your property, our Instant Quote service allows you to obtain pricing quickly and arrange the appropriate inspection.
Get your Instant Quote today and arrange a Defect Analysis inspection with Stokemont.
The key principle is simple: find the source, stop the moisture, allow the building to dry, then repair the damage.
