When I was growing up, winter had a way of seeping into our home. I remember lying in bed, watching my breath form little clouds in the air, huddled under layers of blankets, waiting for the morning sun to take the edge off the cold. The walls of our house felt more like a sieve than a shield, letting the warmth drift away as quickly as it arrived.
Our old family home, built long before insulation was even a consideration, had its charm - but energy efficiency wasn’t part of it. The gas bill would arrive like an unwelcome guest, always bigger than expected, while we still spent the season wearing extra jumpers indoors. It didn’t seem fair - how could we be paying so much, yet still be cold?
Years later, working as an architect, I came to understand the problem. Heat loss. Cold bridges. Poor insulation. The house wasn’t failing - it was just built for a different era. It wasn’t designed for sustainability, for comfort, for efficiency.
But here’s the good news: we can fix this.
Douglas House - a low energy home in Kensal Rise, North West London
We are in the middle of an energy crisis - both personal and global. Our homes leak heat, and we pay the price. Financially. Environmentally. Comfort-wise.
And it’s not just about money. It’s about how we feel in our homes. A warm home is a comfortable home. A comfortable home is a happy home.
Over a third of the heat in a building is lost through the walls. That’s where External Wall Insulation (EWI) comes in. It’s one of the smartest ways to upgrade an older home—wrapping the building in a protective, insulated layer that keeps the warmth in, the cold out, and the energy bills down.
But, like everything in architecture, it has to be done properly.
Thermal imaging camera used to show the affect of external wall insulation
EWI works brilliantly for some buildings. For others, it’s the wrong approach. Context is everything.
The wrong insulation on the wrong house is worse than no insulation at all.
Not all insulation is created equal. What you choose matters - not just for your home, but for the planet.
EPS & PIR (plastic foams) – Thin and effective, but at a cost. These materials have a high embodied carbon footprint and are not breathable, meaning they can trap condensation inside walls if moisture control isn’t carefully managed. While they offer good thermal performance in a small space, their environmental impact is significant.
Wood fibre & cork – The natural choice. Breathable, sustainable, and with a low carbon footprint, these materials allow moisture to escape while still insulating effectively. They work with the building rather than against it, helping to maintain a healthy indoor environment. The trade-off? They require thicker layers and come at a higher cost. But for those thinking long-term - about durability, comfort, and environmental responsibility - they’re a smarter choice.
Phenolic boards – A middle ground. They offer good insulation properties and are more compact than natural alternatives, but they aren't the most eco-friendly option. While they can be a practical solution in certain situations, they don’t match the sustainability credentials of wood-based materials.
Every material choice we make affects not just how a home performs, but how much it costs the environment. Low-carbon, natural materials like wood fibre and cork don’t just keep homes warm - they also keep our planet cooler by reducing embodied carbon emissions.
The best insulation? It’s the one that doesn’t just work for your home today - it works for the future too.
EWI changes how a building looks. That’s not always a bad thing. Many homes - especially mid-century ones - could do with a design refresh. The right insulation system can actually improve the aesthetics of a building.
But if you live in a conservation area, or a listed building, you might not be able to use EWI at all. In these cases, internal insulation (IWI) might be the better option.
And then there are the practical changes:
It’s not just a case of slapping insulation on a wall. It’s about thinking holistically.
Let’s be honest - EWI isn’t cheap. It costs between £100–200 per square metre, and that’s before you factor in other costs (scaffolding, detailing, adjustments).
But then, energy bills aren’t cheap either.
If done properly, EWI pays for itself over time. It’s an investment in lower heating costs, better comfort, and a home that’s future-proofed against rising energy prices.
There are grants available through the Energy Company Obligation (ECO) scheme, which provides funding for low-income households. If you’re eligible, it’s worth exploring.
But even if you’re not, think long-term. A well-insulated home costs less to run, lasts longer, and is more enjoyable to live in.
At RISE Design Studio, we don’t believe in quick fixes. We believe in intelligent, long-lasting solutions.
EWI isn’t a silver bullet. But for the right home? It’s a game-changer.
Here’s what to remember:
A home isn’t just a place to live. It’s a place to thrive. And a well-insulated home? That’s a home that works - for you, for your family, for the planet.
At RISE Design Studio, we believe in architecture that stands the test of time. That means designing with care, intelligence, and responsibility.
Because the best homes? They don’t just keep us warm. They keep us well.
If you would like to talk through your project with the team, please do get in touch at architects@risedesignstudio.co.uk or give us a call on 020 3947 5886
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