Damp
Penetrating damp investigations
Investigation of moisture entering through walls, roofs, openings and rainwater goods.
What the issue is
Penetrating damp occurs where water passes through the building envelope from outside. It is often intermittent and closely linked to rainfall, wind direction and the condition of external details.
Common symptoms
- Damp patches that appear or worsen after rain
- Staining below windows or at wall heads
- Damp around chimney breasts
- Localised mould in one area only
- Water marks on ceilings
Likely contributing factors
- Blocked or leaking gutters and downpipes
- Cracked render or failed pointing
- Defective window seals and sills
- Roof and flashing defects
- Cavity debris or wall tie bridging
Conditions that may be mistaken for it
- Condensation in cold corners
- Rising damp at low level
- Internal plumbing leaks
- Escape of water from appliances
How the issue should be investigated
- External elevation inspection, including rainwater goods
- Correlating damp locations with external features
- Assessment of render, pointing and openings
- Roof and chimney inspection where accessible
- Moisture mapping internally
Potential treatment or repair options
- Repair or replacement of rainwater goods
- Repointing or render repairs
- Sealing and flashing repairs
- Cavity clearance where appropriate
- Redecoration once dry
When treatment may not be appropriate
- Where the source has already been repaired and the wall is drying
- Where internal tanking would mask an untreated external defect
Factors affecting the cost
- Height and access, including scaffolding or towers
- Extent of external repair
- Materials to match existing finishes
- Number of elevations affected
What to expect during an inspection
Expect an external inspection in addition to internal readings. Weather conditions on the day can influence what is visible.
Final recommendations always depend on the property, the inspection findings and the confirmed cause. Elevated readings alone do not confirm rising damp, not every mould problem requires extensive treatment, and damp-affected plaster does not always need replacing.
Frequently asked questions
Next step
Not sure which inspection you need? Start with a few questions.
Tell us what you are seeing and we will set out what is likely, what is uncertain and which inspection would answer the question. Speak to us on 0333 335 6152 if you would rather talk it through.