Water Getting In From Outside
Penetrating damp happens when moisture enters a property from outside – through a defect in the roof, brickwork, render, pointing, flashing or rainwater goods. It’s often more noticeable after heavy or persistent rain, and it can appear anywhere, not just at low level.
The damp patch inside isn’t always where the water is getting in. Moisture can travel through a wall before it ever shows up on the surface.
That’s why we inspect the property from the outside in, rather than assuming the internal damp patch marks the exact source.
Signs Of Penetrating Damp
Patterns vary depending on the source, but common signs include:
See our Damp Proofing overview for how these signs can also point to rising damp or condensation instead, or read our guides: Penetrating Damp Explained and Chimney Breast Damp & Hygroscopic Salts.
Common Causes We Look For
Finding and repairing the actual source of the moisture is essential – without it, the problem simply returns.
Our Penetrating Damp Repair Process
Exterior Inspection
We inspect the roof, walls, flashing, pointing, render and rainwater goods to trace where water is actually getting in.
Honest Explanation
We explain exactly what we’ve found and what work is needed – and what isn’t.
Repair The Defect
As a roofing and building company, we carry out the repair ourselves – whether that’s roofing, flashing, brickwork, render or guttering.
Internal Finish
Where internal plaster or decoration has been affected, we can also carry out the remedial repair once the property has dried out.
Why Choose KJ Roofing & Building?
Frequently Asked Questions
How do you find where the water is actually getting in?
We inspect the property from the outside – roof coverings, flashing, chimney masonry, brickwork, pointing, render, window and door surrounds, and rainwater goods – since the entry point isn’t always where the damp is showing internally.
Why does the damp patch inside not match where the leak is?
Moisture can travel through masonry before it becomes visible on an internal surface, so a patch inside doesn’t always sit directly below or behind the actual defect. This is why an external inspection matters more than just looking at the internal damp patch.
Can you repair the cause yourselves, or do I need a separate contractor?
In most cases we can carry out the repair ourselves – roofing, flashing, brickwork, pointing, render and guttering are all work we do. You won’t usually need to find a separate contractor for the fix.
Will you also repair the internal damage?
Yes, where needed. Once the source has been repaired and the area has had a chance to dry out, we can carry out remedial plastering and finishing work.
Does penetrating damp only happen in old properties?
No. While older properties can be more susceptible due to their construction, penetrating damp can affect any property where there’s a defect in the roof, walls, render, pointing or rainwater goods – regardless of age.
Do you offer a guarantee on penetrating damp repairs?
We stand behind our workmanship on every job. Ask us for the specific guarantee terms that apply to your repair when we provide your quote.
Water Getting In Somewhere It Shouldn’t?
Get in touch and we’ll trace the source before recommending any repair – no pressure, just an honest assessment.