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Insulation – why you should still think about it during summer

Making sure your home is well-insulated is crucial from an environmental and energy-saving perspective

As we make our way into summer, insulation is probably the last thing on your mind. However, insulation isn't just designed to retain heat – it also keeps it out, which will help you stay cool during hot summer days.

With the cost of living a big concern for all of us, it's likely you're looking for ways to cut your spending. Ensuring your home is properly insulated will keep your energy bills down during winter, plus it keeps your home cool during a hot summer, making it less likely that you'll need an energy-guzzling air conditioner. 

Below, we take a closer look at the benefits of insulation. Plus, you'll spot some expert tips on how to prepare your home for winter.

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How insulation works during summer

The UK is heating up. According to the UK State of the Climate report (published in July of last year), recent decades have been warmer, wetter and sunnier than the 20th century. In fact, the report also claims that all the top 10 warmest years for the UK in the series from 1884 have occurred since 2002.

Typically, a British summer doesn't last very long, which is why most of us don't have a home-wide air conditioning system. 

Plugging in a fan usually stored away in your cupboard will provide some relief (check our electric fan reviews if you're currently shopping for a fan) but clearly its powers will be limited. 

A portable air conditioner will keep your home cooler, and, again, we can point you towards the best air conditioners should you need one. However it will be expensive, a hassle to store in between summers if you don't have much space, and will use plenty of energy – helping neither the environment nor your bank balance. 

Effective insulation can help you deal with hot weather, as it limits the amount of heat that can travel through the walls and roof, meaning your home stays cooler for longer. 

Loft insulation is a relatively cheap and effective way to keep the heat out - or in. The Energy Saving Trust says that a quarter of heat is lost through the roof in an uninsulated home. It adds that, if installed correctly, loft insulation 'should pay for itself many times over in its 40-year lifetime.'

In many cases, you should be able to install loft insulation yourself – invest in some rolls of insulation and lay it between the joists making up the floor of your loft. Add a second layer at right angles to achieve the minimum recommended depth of 270mm.

If you need to lay boards on top, use spacers to make sure the insulation is not being squashed down as this reduces its effectiveness. Read helpful tips for insulating your loft from Which? Trusted Traders

Installing insulation at joist level means the roof space above will still get hot in summer (and will be cold in winter). If you plan to spend time in your loft space, or store temperature-sensitive items there, insulating at rafter level - the underside of the roof, as in the photo below - may be a better choice. It's often more expensive and usually needs professional installation, but your loft will be cooler in summer and warmer in winter.

For more details on loft insulation and how much you can expect to spend, see our guide on loft insulation costs and savings.

Dealing with the heat

If the air outside is warmer than it is inside, you need to keep that air out to avoid an uncomfortably warm house during summer. Insulation won't be as effective if, on hot days, you open all the windows. In the evening, however, you'll need to use ventilation to bring cool air into your home.

To cope with hot temperatures, you can try using an electric fan. Our electric fan reviews reveal which models make a noticeable difference to how hot you feel without generating lots of noise.

Taking a shower using cool or lukewarm water can also help, especially if you let yourself air dry rather than reaching for a towel.

For more tips on dealing with a hot summer, see our advice on how to keep cool without air conditioning.

Electric fan

Use the summer to prepare your home for winter

Although we're still in summer, it's a good idea to think about any jobs that'll need taking care of before or during winter.

Try to make sure that your insulation is up to scratch before it starts to get chilly, as it could save you from wrapping yourself up in a blanket at the end of the year or paying a lot more in heating bills. 

We also recommend getting your boiler serviced during the summer. Towards the end of the year, boiler professionals are in high demand, so acting sooner rather than later could potentially help you avoid an emergency call-out. See our guide on getting the best boiler service for more details.

You might also want to consider:

  • Clearing your gutters – removing debris from your gutters will prevent water from pooling and causing leaks
  • Checking your roof – tiles can loosen throughout the year, so it's worth having a look to see if any slates need replacing. Note that a build-up of moss can obstruct drainage points, too
  • Tidying up the garden – prepare your garden for winter by making sure nothing will get swept away. Remember to cover up (or pack away) garden furniture and check that your garden lights are working correctly
  • Bleeding your radiators – It's a good idea to do this at least once a year so you're getting the most out of your heating. If your radiators are warm at the base but cooler at the top, this is a sure sign they need bleeding. Check out our guide to bleeding your radiators.
  • Test your smoke alarms – colder temperatures will have you turning up the heating and using your fireplace if you have one, so ensure your smoke alarms work correctly
  • Check for overhanging branches – if you have branches dangling over parts of your roof, cut them back to ensure no damage is caused during winter storms.
Examine gutters and downpipes

Many of the UK's homes are inefficient to heat, which is why we've put together a handy guide on how to make your home more energy efficient.

Contacting a Which? Trusted Trader

If you need professional help insulating your home, consult a Which? Trusted Trader.

The Which? Trusted Traders scheme recognises reputable traders who pass a strict assessment process. Before a trader can earn their 'Trusted Trader' title, we check the trader's credit reports, customer satisfaction and business procedures, as well as conducting an interview and assessment.

To find a reliable local trader, head to the Which? Trusted Traders website and enter your postcode.