How to Keep your Home Cool During the Heatwave

How to keep your home cool

With the weather staying consistently hot for the longest time since 2013, Jason Orme and Julia Kendell, property experts for The London Homebuilding & Renovating Show (21-23 September, ExCeL, London;, provide their advice on how to keep your home cool.

homeJason Orme, property expert for The London Homebuilding & Renovating Show (21-23 September, ExCeL, London;, offers his structural advice below:

“There’s a whole range of things you can do structurally to keep your home cool but it’s best to carry them out at the same time as the renovation. For people who aren’t renovating or self building, it is quite a significant job which creates a lot of upheaval and I suspect somebody who suffers from the heatwave will be thinking about doing improvements to the house next year rather than expecting a significant change overnight.

“Insulation works both to keep warm areas warm and keep warm air out from properties. As a result, homes that have the highest insulation tend to be the coolest during summertime and warmest during wintertime. The best is the foiled-back insulation which is available as rigid foam insulation boards varying from 25mm to 100mm.

“You can buy boards from builders merchants which are priced at around £15 for a 1.2m x 2.4m board in addition to putting the plasterboards in and finalising the look. In terms of the comfort that it brings, it is the only way to assure that the air outside doesn’t get inside. The majority of houses in the UK are concerned about warm air leaking out during the cold times but also warm air leaking in during summertime so windows and doors thoroughly sealed and airtight will help with both matters.

“Modern homes recently tend to have divides with more glass than concrete, as people are after bigger windows and smaller walls. It’s all very well insulating the walls but it’s the windows that are the weak point for energy efficiency and overheating. Properties with big expanses of glass can get warm very quickly and this often comes down to the specification of the window and the glass. There are coatings you can apply to windows to minimise sun glare effectively. Other options consist of internal injections with gas between the panels as they can help keep the heat and sun out.

“When we go on holiday to sunny countries such as Greece and Spain, you notice that the homes are built to withstand excessively high temperatures, as they are equipped with very thin walls, usually made out of concrete. The general view is that big thick walls tend to keep the interior cooler rather than those built with materials such as timber, which is a relatively thin wall system that can build up heat pretty quickly.

“The northern facing rooms tend to be a lot cooler than the rest of the house. If you are renovating a house to try to withstand excessive temperatures you need to think about positioning the main rooms to face the north or have options to sleep in additional bedrooms or open areas.

“The absolute principle, which is followed by passive houses, is about temperature management and air control and a design element which protects against overheating, and these don’t have to come necessarily from the structural solutions. For example, verandas are very good at keeping the direct midday sun out. If you retain trees around the house and in the garden you can benefit from the perks of having natural shading solutions.”

Design Tips

Julia Kendell, interior designer from ‘DIY SOS’ and spokesperson for The London Homebuilding & Renovating Show (21-23 September, ExCeL, London;, adds homeher design tips.  

“As the weather heats up, it’s in our nature to overreact and be in a rush to redesign our entire homes to keep us cool. But we should be mindful that our weather is, sadly, not the same all year and any structural changes or redecoration should provide benefit throughout the seasons. The key is to balance the highs and lows of our climate ensuring a comfortable living experience 365 days a year. 


“If glazing is not high-performance double or triple on south and west-facing windows, your home can become like a greenhouse attracting 30% of unwanted heat through the windows alone. The larger the glazing area, the more significant the greenhouse effect will be. Installing new, high-rated insulation, well-fitting windows will tackle heat ingress in the Summer and heat-loss in the Winter months.

“For those with bedrooms on the top floor it’s recommended to keep blinds down or curtains shut during the day to block the sun and diminish the build-up of heat upstairs. Blackout-lined curtains and blinds from companies like will almost entirely block glare and heat penetration, with the added benefit of blocking street-light and the early dawn light which can disturb sleep at night. 

“Window films, commonly used in conservatories, are helpful in all south and west-facing rooms when it comes to reducing glare and filtering out UV rays which can damage the furniture or curtains. At you can find film available on a roll or bespoke to fit your glazing requirements. It is also available in an opaque and patterned finish if privacy is an issue.

“As heat rises, If space and planning allow, install roof-light windows  as the more air you can let out at the end of the day through the roof, the cooler the upstairs will become creating a comfortable sleeping temperature. Open attic/loft hatches to allow the heat to escape in to the roof space. Insulation in the roof not only keeps your home warmer in the Winter, thus reducing energy costs, but has a huge effect on keeping the property cool in the Summer too. 

“For living rooms in which you don’t want to cut out light completely during the day, shutters in light colours will reflect light and heat back outside and can be opened to whatever angle provides the best combination of light, privacy and heat reduction. produces and installs made-to-measure shutters to suit any window.


“Carpeted flooring traps heat, so solid flooring, particularly tiling, is a better option for cooler interiors and has the advantage of making a space appear larger and brighter too. During the Winter, a rug can be added to the scheme to create a cosy, warm feel.  


“Dark colours absorb energy and will make a room feel warmer and more claustrophobic in the summer months. White and light colours will reflect the light energy back helping to regulate the temperature. Balance this with glare-reduction at the windows. 


“Change any remaining incandescent bulbs or old, inefficient bulbs for new LED replacements. Incandescent bulbs produce 90% heat to only 10% light and the accumulation of heat given off from old light fittings can make a huge difference in a home.


“Excessive heat can cause sleep discomfort so it’s not advisable to use the same bedding type all year round. A breathable material can ease sleep struggles and companies such as Soak and Sleep have 2.5 tog duvets with silk fillings which won’t create overheating whilst maintaining a degree of ‘weight’ to them. Avoid manmade materials and choose 100 per cent cotton or linen bedding for the most comfortable night’s sleep. Buckwheat pillows have been used in Japan for centuries for their temperature controlling and orthopaedic properties – Plantule”