Tips to keep your house cool in a heatwave

We all need some advice on how to keep your house cool in a heatwave and Ealing resident Kate Watson has done comprehensive research and testing on what works best to have a cool house in a heatwave.

A headline in the Guardian on 30 June 2026, about living through the heatwave in Paris reads “It feels as if we are being abandoned to our fate by those in power, with further extreme heat expected next week” and we agree. We are at a point where we must act now to make our homes and communities as resilient as possible to the certainty that we will need to protect ourselves from heatwaves at temperatures never experienced before. We need solutions that are cheap, accessible and effective.

Governments struggle to provide some of these solutions because they don’t work uniformly in every home or work space, so the most practical way to protect yourself is by knowing all the options, and then using the ones that best suit your environment and needs.

Advice to keep your house cool in a heatwave

Kate Watson, Ealing resident and climate carer, shared her tips with ActForEaling.

Here is Kate’s comprehensive list of things they have done in their house:

1. Seal up all gaps around doors and window frames whilst ensuring air bricks and vents are clear to ensure good air flow
2. Use multiple layers inside and outside windows and doors to create a complete buffer from the elements. Kate cannot stress enough just how much hard work each of these layers do. However, when you combine them all together, that’s when it really starts to work super well. By doing this you will have stopped an extra 7-10 degrees of heat entering your home. So here is what Kate has done:
   • First layer starts with trees and shrubs. Plants absorb a huge amount of heat against a house so they are your first defence barrier against extreme heat. There is a street tree planted by the council, tall olive trees reaching to first floor infront of the house, dense shrubs infront of those, a jasmine climber round the porch, all creating a heat barrier before we even got to the fabric of the building.
   • Then there are have window shades that are hung out and roll up and put away in autumn. These are of a solar resistant fabric made by a manufacturer called Serge Ferarri and it’s perforated so light filters through but the sun is reflected away.
   • Behind that there is have double glazing sash windows which is open and shut top and bottom around the path of the sun and heat. The windows have solar film on them.
   • Then have internal thermal blinds and curtains.
3. Back of the house there is the same arrangement of layers with bifolds and windows. Plus a huge sail shade covering the patio which creates another buffer to sun and heat getting near the walls and windows.
4. Asphalt flat roofs have painted with reflective paint.
5. Garden office has a dense climbing plant growing over the top and now covers that roof with a foot thick of greenery. It’s left it to cascade down the front of the office creating more shade.
6. Water feature on the patio as water helps to cool the air near the house.
7. Although a sunny garden, by planting lots of small trees and shrubs its created patches of glady shade.
8. Opening and closing windows (and veluxes in the loft) makes a huge difference. Get good at it, learn how this works and you will thank yourself. Read BBC article on making the most of your fan.
9. Ground floor is well insulated and extra air vents were added to ensure great air flow. Keep your air bricks clear.
10. Blocked up the chimney and removed gas fire, as it made a huge difference in winter to keeping the house warmer.
11. Mobile air con unit on two of the worst days but throughout the heat wave the house didn’t go above 26 and it was 33-37 degrees outside. Without all the other adaptations they doubt the air con would’ve been anywhere near as effective or efficient. Now the weather has cooled, the house has quickly returned to a cool temperature.

Intense Heatwaves

Kate also shared with us they have now experienced two really intense heatwaves in their home in the last few years. The first one, she has a terrible memory of sitting on our sofa in the kitchen, feeling absolutely helpless, unable to work, think straight or know what to do.

“The heat in the house must have been about 31 – 32 degrees, although we had no way of knowing because we had no monitoring device to confirm it. There was no where to go and no respite. We were caught by surprise and I felt very vulnerable – more than I had ever felt inside my own home.

Three years later it was a totally different story. On the hottest days the house didn’t go above 26 degrees according to our temperature monitor, and although it was hot and not quite as cool as I’d have liked, we were able to cook, work, sleep and move around the house without any issues.”

Next Steps

Kate has plans for a few minor adjustments to make:

1. Buy solar film for the Velux windows in the loft. It must be external for Velux windows.
2. Looking into alternatives to planet wrecking air con. Italy has used mini heat pump models since the 50s, that don’t need piping through the house and are far less damaging to the planet. This may be the first significant investment to protect against even more severe temperatures in future.

Beyond that they will keep demanding better from our governments. Encourage them to decouple electric from gas prices. Also to push ahead with the Green and clean energy economy and plant more trees. As a community we can help each other to adapt and learn how to exist in a very changed world.

About Kate Watson

I’ve lived worked in Ealing and Europe as an interior designer for over 20 years and spent many years researching products of every sort for properties, both residential and commercial. Unfortunately the interiors and architectural and building industries don’t always make climate resilience a primary part of their remit, for a variety of reasons too long to discuss here. I’ve also always been interested in ethical, eco friendly solutions in design and so wanted to find ethical and passive thermal solutions to our own home. This research took me on a virtual journey around the world, looking at how other historically hotter countries managed temperature on small cost outlay. Pioneers like Laurie Baker in India, and Middle Eastern building and landscaping design helped to form my greater knowledge base, which I could then modify with locally available materials both traditional and modern technical fabrics. 

My husband did his degree in physics which was invaluable in working out thermal resistance within our home and the immediate external environment. Together we came up with solutions that were cost effective, required minimal disruption, and shifted our home outside of the overheating zone. The more people who develop this knowledge and share it, the more people will be able to stay safe in cold and hot extremes.

Kate’s recommendations

Here is a list of suppliers used for these changes and additions around the house.

• CJMarine.co.uk – Serge Ferrari Soltis fabric . Easy to put up a few days before the first hot day while the air inside is still cool, then roll up and store in the shed 
• Primrose.co.uk – water features
• Wholesale glass company.co.uk – solar 20 film
• Rawlinspaints.com – Blackfriar solar paint
• Steelwirerope.com – tension wire kits
• Brass tacks fittings.co.uk – floor ventilation grilles
• Screw fix – storm guard brush strip to seal drafts 

ActForEaling

For more climate positive actions you can take see ActForEaling’s 10 Steps for a Greener Ealing. You can also join our mailing list.