Condensation is a common problem in old and new properties alike. The first signs are usually the appearance of black mould spots and a musty smell in the coldest parts of the house – usually in bedrooms and bathrooms. If your property has been free from these signs in the warm summer months, then it is unlikely to be a damp problem created by defects in the property – condensation is the most likely cause.
What is Condensation? Condensation is a process where moisture (steam) in the air inside your home is condensing-out into water droplets on cold surfaces. This is most noticeable on hard surfaces like glass or tiles, where pools of water may appear on window sills. With soft surfaces like wallpaper, carpets, bedding and clothes you will not notice the water, but it will be absorbed into these items making them cold and damp and over time resulting in mould and mouldy smells.
What causes Condensation?
There are three main causes of condensation in a home:
- Rooms that have cold surfaces, either from lack of insulation (e.g. double glazing) or from inadequately heated.
- The production of too much steam from cooking, washing, showering, clothes drying etc – all result in moisture laden warm air which will rise to the highest and usually the coldest part of the house, where condensation takes place.
- Inadequate ventilation of the steam produced at source, which keeps it all in the sealed envelope of the house. Modern houses with double glazing and draft proofing are effectively hermetically sealed boxes, with little or no venting of excess moisture as and when it is produced, for example a bathroom shower or cooker.
How can I prevent Condensation and Mould? You can, actually, do a lot to prevent condensation in your home and it’s fairly simple to do.
- Maintain a minimum and consistent temperature in all your rooms especially bedrooms and bathrooms – temperatures should not be allowed to fall below about 18c.
- If you are out all day, leave some heating on to keep the house warm – it costs less to maintain the temperature than to warm-up from cold, and it’s much more comfortable.
- Minimise the amount of steam you produce when cooking (keep lids on pans etc) and washing, and always vent this to the outside, for example by opening a window or using the cooker extractor fan.
- Always confine steam to the room it is produced in by keeping internal doors closed.
- Avoid drying wet clothes on radiators and try to keep wet things out of the house by leaving them in a porch, utility or garage.
- Make sure electric clothes dryers have an external vent.
Measures such as these will cure most problems of condensation and mould. However, if the property has become very cold and damp over a long period it may take some time to dry everything out thoroughly with good heating, so that surfaces are no longer cold and damp.
Please feel free to share these tips with your tenants to ensure your property is protected against the build up of mould. Fingers crossed spring comes quickly and is followed by a lovely warm summer!
