Eco-friendly insulation

What makes insulation eco-friendly

Three things: what it's made from, how long it lasts, and how much heating it saves. The last one matters most. A well-insulated house burns less gas, oil or electricity every winter for decades.

The materials we use

• Knauf Earthwool: mineral wool made largely from recycled glass, with a plant-based binder and no added formaldehyde. Efficient and good value.
• Wood fibre: made from timber by-products, stores carbon, breathable, best for stone walls and attic rooms.
• ThermaFleece sheep's wool: natural British wool, breathable, safe to handle.

What we won't use

We never install spray foam in homes. It traps moisture against roof timbers, it's very hard to remove, and lenders increasingly refuse houses that have it. We remove it for people who are stuck with it.

Wood fibre · Sheep's wool · Loft insulation · Grants

The materials we use

• Knauf Earthwool: mineral wool made largely from recycled glass, with a plant-based binder and no added formaldehyde. Our everyday choice for lofts and floors.
• Wood fibre: made from timber offcuts, breathable, and the best option for stone walls and attic rooms.
• ThermaFleece sheep's wool: natural British wool, breathable and safe to handle, ideal for older roofs.

The most environmentally friendly thing insulation does is cut how much heating you use. The second is lasting: breathable materials on old buildings avoid the damp problems that lead to insulation being ripped out. That's why we never install spray foam in homes.

Wood fibre · Sheep's wool · Loft insulation