Shotton Flat Condensation & Mould Case Study
Widespread condensation-driven dampness and mould growth from inadequate ventilation, elevated humidity, and cold internal surfaces. Dew-point conditions confirmed at inspection.
Overview
Location: Shotton, Deeside / Flintshire (CH5 area)
Property type: Flat (solid wall influences thermal behaviour)
Survey fee: £475
Occupants experienced dampness and mould growth. Environmental monitoring confirmed active condensation risk, with surface temperatures in multiple rooms below calculated dew point levels at the time of inspection. Ventilation provision was inadequate, with underperforming intermittent extract, lack of background ventilation and restricted internal air paths. No indicators of rising damp or penetrating damp were identified at accessible surfaces during the inspection.
Findings
- Environmental monitoring confirmed active condensation risk: multiple internal surfaces below calculated dew point at the time of inspection.
- Ventilation provision was inadequate: underperforming intermittent extract fans, lack of background ventilation, and restricted internal air paths.
- Solid wall construction, localised thermal bridging and limited heating in some areas increased cold-surface condensation risk.
- No indicators of penetrating damp or rising damp were identified at accessible surfaces during inspection; observed dampness aligned with condensation and moisture retention.
Recommendations
- Improve extraction performance (upgrade/commission fans; consider continuous extract strategy where appropriate).
- Add background ventilation and ensure air transfer paths between rooms support effective moisture removal.
- Address cold-surface risks with targeted insulation/thermal bridging improvements where feasible and maintain steadier heating to reduce dew point crossings.
Outcome
By treating the correct moisture mechanism first (condensation + ventilation), the plan reduced mould risk and avoided inappropriate assumptions about “rising damp”.
FAQs
Is mould proof paint enough?
It can mask symptoms but won’t fix the cause. If condensation and inadequate ventilation are driving mould, improving air change and reducing humidity is the durable fix.
How does ventilation reduce damp and mould?
Ventilation removes moisture-laden air and lowers indoor humidity, reducing dew point events on cold surfaces where condensation and mould develop.
What changes usually make the biggest difference?
Effective extract ventilation (ideally correctly sized/commissioned), adequate background ventilation, clear air transfer paths, and steadier heating to raise surface temperatures.
Next steps
If damp is being blamed on “rising damp”, an independent condensation/ventilation-led assessment can usually confirm the real moisture mechanism quickly.