Loft Insulation Material Comparison

Material choice depends on timber breathability, property age, budget, and environmental goals. Here is how the four main material types compare.

1. Glass & Rock Mineral Wool

The UK's most widely specified loft floor insulation. Glass or rock fibers formed into flexible rolls laid between and across ceiling joists.

Pros: Euroclass A1 non-combustible fire rating, highly cost-effective, proven thermal performance.

Best For: Standard modern or post-1920 homes seeking maximum insulation value per £ spent.

A 100% natural, sustainable insulation roll made from sheep wool fibers treated with eco-friendly insect repellent.

Pros: Highly breathable, buffers airborne humidity naturally without losing thermal value, non-irritant to handle.

Best For: Traditional, Victorian, or timber-frame homes where breathability is paramount.

Loft rolls manufactured from recycled PET plastic bottles, offering itch-free handling and strong eco credentials.

Pros: Non-itchy, long-lasting durability, strong recycled content story.

Best For: Homeowners wanting soft handling and sustainable recycled plastic materials.

Thin, multi-layer reflective foil insulation installed at rafter level rather than on the loft floor.

Pros: Reflects radiant heat, space-saving thickness at rafter level.

Best For: Warm-roof setups or room-in-roof conversions where floor joist roll depth is constrained.

Our survey team helps you pick the right insulation.