PRBG Environmental

To stop condensation on windows you need to lower indoor moisture and improve ventilation, for example by using kitchen and bathroom extract fans, opening trickle vents and avoiding clothes drying indoors. Keeping rooms gently heated and improving insulation or glazing helps keep the inner glass warmer so moist air is less likely to condense.

On its own, condensation is just water, but if it appears most days it can quickly lead to black mould on frames, sills and nearby walls. Over time this can damage paint, timber and plaster, and may affect people with asthma or allergies.

No, condensation usually comes from everyday moisture like cooking, showers and breathing, not from the ground. However, if it is ignored it can create similar looking staining and mould patches, so a survey helps confirm the true cause.

Cool, wet winters, airtight homes and insufficient ventilation mean warm moist air from daily activities condenses on cold surfaces such as windows and external walls. Properties in areas like Cardiff, Newport and Swansea often have older construction and upgrades that trap humidity inside.

PRBGE carries out condensation surveys to check humidity levels, cold spots, ventilation and insulation in your property. We then recommend targeted solutions such as PIV or HRV systems, better extraction and surface treatments to control moisture long term.

Good ventilation significantly reduces condensation by removing moist air before it can settle on cold glass. In many homes, combining mechanical ventilation with sensible heating and insulation is enough to stop daily window condensation.

Use existing extractor fans whenever you cook or shower, keep lids on pans, dry clothes outside or in a vented dryer, and open trickle vents or a window slightly when safe. Wiping down wet glass and sills each morning also protects frames while longer‑term solutions are put in place.