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Penetrating Damp Around a Front Bay on Adelaide Avenue, Brockley SE4
A house on Adelaide Avenue in Brockley had damp in the front reception room around the bay window, and a damp feeling utility room on the lower ground floor.
Project at a Glance
The Brief
The owners wanted the causes of damp in two different parts of the house identified.
The Survey
On the ground floor front elevation, the render was cracked and the pointing and sealant around the window frames had deteriorated. Open joints, cracked render and weathered finishes around the bay were letting rain in, causing penetrating damp in the front reception room.
In the lower ground floor utility room, which had been tanked before, readings were mixed, pointing to intermittent moisture rather than active water ingress. The extractor fan there was broken, and the lack of extraction was causing high humidity and condensation.
The Solution
Targeted repairs:
- Rake out and renew defective pointing around the window frames.
- Replace failed external sealant joints and repair the cracked render.
- Replace the utility room extractor with a humidity controlled smart fan.
The Work
Advanced Damp carried out the external render and repointing work from 14 to 17 September 2026.
The Result
The bay was made weathertight again, and the utility room problem was shown to be ventilation, not a failed tanking system. See our page on damp proofing in south London.
Frequently Asked Questions
Can damp come in around windows?
Yes. Failed sealant, cracked render and open joints around frames are common routes for rain.
Has my tanking failed if the room feels damp?
Not necessarily. Here mixed readings and a broken fan pointed to condensation, not water coming through.
What does a smart extractor fan do?
It switches on automatically when humidity rises, removing moisture before it condenses.
Damp around windows?
Our CSSW and CSRT trained surveyors find the real cause before recommending any work. Non-invasive survey with a clear written report. No obligation.
Survey carried out by Lionel Sewell (FODCS) at Advanced Damp. Project completed in Brockley, SE4.
Sam Fitzgerald is the founder of Advanced Damp and a working damp and structural waterproofing surveyor diagnosing and treating moisture problems in residential and commercial properties across London and the South East. He is FODCS certified (a Federation of Damp Certified Surveyor) and a member of the Federation of Damp. His hands-on work covers rising damp, penetrating damp, condensation, basement waterproofing to BS 8102, and thermal imaging surveys, and he has personally completed over 400 damp surveys across properties of every type and age. Everything he writes draws directly from jobs he has carried out. He does not write about treatments, products or causes he has not dealt with first-hand in the field.
