Energy efficient ventilation at home

Ventilation is extremely important. Without proper ventilation, a home can suffer from various types of damage, the most common of which is rot (whether in roof-space, wall cavities, or below-ground). Importantly, ventilation also allows oxygen to enter into your home, as well as allowing water vapour, fumes, and carbon dioxide to leave it.

Although ventilation is undoubtedly a good thing, it is also important not to have too much of it. The most obvious negative side-effect of too much ventilation is heat loss; and if your house loses heat unnecessarily, this can lead to increased energy bills.

When should I ventilate my home?

Knowing when to ventilate, therefore, is crucial. The first thing to remember is that when your heating is on, all windows should be closed, otherwise much of the heat that you’re paying for will leak out unnecessarily.

In fact, most houses have enough ventilation via the natural leakage of air. This natural leakage is usually sufficient to achieve a stable exchange of oxygen and carbon dioxide in your home, and it is also usually enough to allow the exit of water vapour (such as that released when drying clothing).

There are occasions, however, when ventilating manually – through for example, opening windows – is especially important. Kitchens, after boiling a kettle or cooking food and bathrooms after taking a hot shower or bath, are at risk of damp if the excess water vapour is not allowed to leave rapidly.

Read more: Carbon Monoxide poisoning - what are the risks?

While it is normal to open windows in bathrooms and kitchens, other rooms generally do not need ventilating in the same manner. If you find that you regularly need to open windows in other rooms, this could be a sign that your heating is set too high. For central heating systems, make sure your thermostat and radiators’ valves are not at too high a temperature. If this does not rectify the issue, then there may be a problem with the thermostat itself.

Finally, always remember that warmer air holds more moisture than cold air, and that condensation is less likely to gather on warm surfaces. It is therefore important to ensure that the regulation of cold and hot air through ventilation is controlled: too much cold air can be just as bad as not having enough.