Why do retrofitted homes feel so much better all year round? – CIJA? | Ep.48

We all know the feeling of walking into a home that just feels right, but it’s harder to put your finger on why. Here’s an interesting one: two homes can be sitting at exactly the same internal temperature, yet one feels noticeably more comfortable than the other. So what’s actually going on?

In this week’s episode, Andy Banister breaks down why retrofitted homes feel so much better across the whole year, and it comes down to three things working together: continuous insulation, airtightness and a good ventilation strategy.

Take a cold winter’s evening. You could have the heating turned right up, but if the house is draughty you’ll still feel uncomfortable, which pushes you to crank the thermostat even higher to compensate. There’s a second, less obvious factor too. Our bodies are constantly gaining and losing heat to the surfaces around us, so if the insulation is patchy and the walls are cold, you’re quietly radiating your own warmth straight into them. Sort out the airtightness and insulate the fabric properly, and those surface temperatures rise. Suddenly the same room feels far more comfortable, even at the same air temperature or a slightly lower one.

The warmer months tell a similar story. An airtight, well insulated and well ventilated home can be cooled overnight and then hold onto that coolness through the day. It’s a common approach across Europe: keep the house closed up while it’s hot outside, then open it up to ventilate once the evening air has dropped. This is where wood fibre really comes into its own. Its low thermal diffusivity and high thermal mass mean it’s very slow to change temperature, keeping interiors cool through a heatwave, often with no air conditioning at all. As long as UK nights keep cooling to the high teens, which they usually do, you can keep a home comfortable in summer just as effectively as you keep it warm in winter.