18 Oct 2023

Poor air quality = condensation + damp + mould

Choice is mindful of the squeeze on household budgets but it is important that tenants are aware of the need to control and manage condensation which contributes to mould growth that may damage your health, home and belongings.

All homes produce some amounts of excess moisture and we are all familiar with condensation on windows and pools of water on window sills. In severe cases, if not managed, this can lead to damp patches on walls and mould growth. In homes, unsightly mould can form around window panes, corners of rooms and behind furniture. Condensation is the first sign that your home is producing excessive moisture or that moisture cannot escape through ventilation. Moisture and mould build up is not only unsightly but can cause damage to clothing, furnishings, decorations and can aggravate certain health conditions.

Where Does The Moisture Come From?

All air contains some moisture. Modern appliances such as dishwashers, washing machines and tumble dryers all produce large amounts of moisture. As many as 20 pints of moisture is added to the air in the home by an average family per day.

How Do The Problems Start?

Generally, the problems start in winter when there is too much moisture in the air which condenses on cold surfaces. In older properties which were poorly insulated and drafty, any excess moisture could easily escape. Today our homes are much better sealed and insulated. Unfortunately excess moisture, once sealed into our homes now makes them prone to problems such as windows streaming with condensation. Excess moisture, if left unchecked, will lead to damp in the building fabric. Double glazing, insulation and draught proofing all help to retain heat, but can make condensation problems much worse by reducing natural ventilation. Since it is neither practical nor desirable to make our homes less-well sealed, the answer is to reduce the amount of moisture we produce and physically remove the excess moisture. If excess moisture is allowed to build-up in the home, moist air will inevitably come into contact with a cold surface such as a window or external wall when the outside temperature falls. At these low temperatures beads of condensation form, initially on windows and then spread elsewhere. Soon the condensation turns into damp and may result in mould spots growing.

How Does The Moisture Spread?

Moist air is never concentrated in one place for long, it will drift around the home. Moisture produced in one room, for example a kitchen or bathroom will circulate around the house, until it finds a cold place where it will condense and create areas of localised damp. This may be a cool bedroom or inside a wardrobe for example. Condensation and damp can, therefore occur in any room of the home. Usually these are the rooms that are least well heated, not necessarily the ones where the moisture was produced.

How Do You Reduce Condensation?

Condensation can be effectively managed by controlling moisture generation, adequate heating and ventilating your home.


• Do not dry your clothes indoors - each load of washing will contain 5-10 pints of water.

• Wipe condensation from windows in the morning and wring the cloth or sponge into the sink.

• Treat mould with a proprietary mould treatment following the manufacturer’s instructions.

• Keep lids on pots when cooking, open a window and use the extractor fan if provided.

• Keep bathroom doors closed during and after bathing or showering. Open the window or use the fan if provided.

• Let fans run or leave windows open for at least 15 mins after showering, bathing or cooking.

• When filling a bath or sink run the cold water first before adding hot to reduce. This reduces steam and will prevent scalding.

• Ensure all rooms are adequately heated even if rarely used.

• Don’t use stand-alone gas heaters as these appliances produce water.

• Don’t cover radiators with curtains or furniture. Keep a space behind furniture to allow air movement and avoid placing furniture against external walls.

• Ventilate properly (ventilation removes stale, moist air). The most effective way to ventilate is to open several windows to allow a through draft.

• Don’t block or close wall, ceiling or window vents.

• Don’t isolate fans or ventilation systems if fitted. They are efficient and cost very little to run.

• Treat mould with a proprietary mould treatment following the manufacturer’s instructions.

In cold weather, opening windows for 5-10 minutes several times a day will remove moist air without allowing the fabric of the building to cool significantly. This method will conserve heat and reduce energy loss as most heat in a property is held within the building fabric (walls, floors etc.) and not the air itself. If you suspect rising damp, penetrating damp such as defective render or leaking pipework please contact us to arrange an inspection.

Further advice is available in your Repairs Handbook. If you have any queries or concerns contact ChoiceServices Centre on 0300 111 2211 or arrange a visit from your Property Services Officer.