Case Study:
Solving a Penetrating Damp Problem Around an Upstairs Bay Window in Henfield
The owner of a Henfield property noticed a persistent damp problem around an upstairs bay window. Penetrating damp in this kind of area is common, especially where brickwork, pointing, sealant around frames, or lead flashings have begun to fail and allow rainwater to find its way in through the external envelope of the building. Left unresolved, this type of issue can damage plaster, paintwork and timber, as well as create cold, uncomfortable rooms.
The customer called us in because the staining and deterioration around the window had become noticeable, and they wanted a long‑term solution rather than a quick cover‑up.
Inspection and diagnosis
Gavin began by carefully inspecting both the inside and outside of the bay window area. He looked for common routes of water ingress such as hairline cracks in render or brickwork, failed sealant joints around the window frame and any defects in the sill or flashings that might be directing water back toward the wall rather than away from it. Inside, he checked the condition of the plaster, paint, and any visible signs of moisture tracking or salts, which help pinpoint how and where water is moving through the wall.
By methodically working through these potential causes, Gavin could distinguish penetrating damp from other issues such as condensation or rising damp and focus on a targeted repair that would stop the ingress rather than just hiding the symptoms.
The remedial work
Once the source of water ingress had been identified and addressed externally, Gavin turned his attention to the internal fabric of the wall around the bay window. The damp‑affected plaster was removed back to a firm, sound surface, taking away contaminated material that could otherwise continue to cause problems such as flaking and blistering finishes.
He then carried out the internal remedial work, applying appropriate materials and finishing coats to restore a clean, smooth surface ready for redecoration. Throughout the process, he worked efficiently, explained the steps to the homeowner in plain language, and kept disruption to a minimum, using dust sheets and regular clean‑downs to control the inevitable mess that comes with tackling damp and plaster removal.
The outcome and customer feedback
By dealing with the underlying cause of the penetrating damp and renewing the internal finishes properly, the upstairs bay window area was left sound, dry and visually restored. The room not only looked better but felt more comfortable, with the homeowner reassured that the problem had been treated at its source rather than simply painted over.
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The customer later shared this feedback: Gavin did an excellent job dealing with the damp penetration issue around the upstairs bay window, worked fast, explained the process clearly, and kept everything tidy despite the messy nature of the work. They were really pleased with the end result and said they would recommend Gavin for any damp work and plastering.
At G Jones Plastering & Damp Proofing, we regularly help homeowners resolve penetrating damp issues like this, especially around vulnerable areas such as bay windows, chimneys and exposed elevations.
Gavin Jones is a City & Guilds qualified plasterer and PCA Qualified Technician with over 25 years of experience, so when he tackles penetrating damp, he focuses on both stopping the ingress and restoring the internal finishes to a high standard.
If you have signs of penetrating damp, such as staining, flaking paint, blown plaster, or damp patches after rain, get in touch to arrange an assessment and discuss how Gavin can help resolve the problem.