Can too much insulation cause overheating?

    March 19, 2014

Last summer the Daily Mail published an article claiming that too much insulation installed under the could cause overheating of homes and endanger old people.

Since we are now approaching warmer weather (or what passes for warm weather in the UK), I thought it would be right to tackle this accusation and explain just why the opposite is in fact true!

How does insulation work?

During the winter, the air inside the home is warmer than the air outside. The insulation slows down the movement of energy from the warm area to the cold area, creating a thermal barrier that means your boiler doesn’t have to work as hard to keep the home warm. The thicker the insulation, and the lower the U-value, the better this thermal barrier is and so the slower the heat will escape the home.

During a summers day when the temperature may hit 30 degrees, the air outside is generally warmer than the air in the home. With the heating off, the house warms up gradually through the day as the walls and roof absorb the heat of the day. But because the air outside is warmer the thermal barrier created by the insulation will again slow the movement of heat, but in the opposite direction. Warm air in the loft will not be able to penetrate into the home as easily, whilst insulation in the walls will prevent them from warming the home as quickly as well.

Will insulation make nights too warm?

It is true that if you home is too warm when you go to bed, insulation will slow the release of heat from the property. This is easily negated by ensuring that you keep the home well ventilated, opening windows, for example. Anyone who doesn’t open their windows in a heatwave is asking for trouble – a bit of common sense is all that is needed!

To be honest there are about half a dozen days a year in the UK where we do find ourselves in the midst of a heatwave conditions, but there is normally about 6 months when we need to have the heating on, so on balance it is clearly better to install the insulation and take action when it is too warm rather than visa versa.

Are there any negatives to installing insulation?

Insulation is a safe, important way to make your home more comfortable, and it will help make your heating bills more affordable. There is absolutely no reason why you should not insulate your home, as long as it is done properly and appropriate measures taken with regards to safety.

Poorly installed loft insulation that does not consider your wiring and lighting can cause fires, but this is easily avoided by capping the light fittings and taking care not to cover wires. Any installer worth their salt should be able to do this. For cavity wall insulation, vents are sometimes required to prevent damp and provide sufficient ventilation for the property.

Is air tightness a problem for air quality?

It is important for your home to have good air quality – poor air quality can be hazardous to health. Having said this, some properties with extreme air tightness, like passivhaus buildings, have very good air quality. They utilise natural ventilation to improve the air, so whilst it is worth considering your air quality, it should not be a reason to avoid installing insulation.

Insulation is vital for your home

Wherever you live and whatever the type of property, insulation is absolutely vital. With spiralling energy costs it will become even more so. Make sure your home is up to scratch and don’t let the papers stop you from keeping your home warm and saving you money!

Installing Cavity Wall Insulation

Need cavity wall insulation? We have scoured the country for the best tradespeople, so that we can make sure we only recommend those we really trust.

If you would like us to find you a local insulation installer, just fill in the form below and we will be in touch shortly!

    Interested in cavity wall insulation?

    I would like to be contacted by local installers

    I am a recipient of state benefits (this helps us figure out what funding you're eligible for)

    Pin It on Pinterest