The numbers behind the warmth.
Insulation is a system. We measure how that system behaves — wall, loft, floor, junction — and we publish what we find.
W/m²K
0.8
Best U-value after EWI install
Earthwool
300 mm
Standard loft insulation depth
annual
−35%
Avg heating bill reduction
EPC
C→A
Typical post-insulation rating
What we measure
Four numbers that decide warmth.
U-value (W/m²K)
How readily heat moves through your walls, roof or floors. Building Regs allow 1.6 for walls. Our EWI system achieves 0.8. Cavity fill improves 1.6 to 1.1.
Insulation thickness
How deep we go. Loft: 300 mm Earthwool standard. Floor: 100 mm between joists. EWI: 60–100 mm EPS or mineral wool board.
Air tightness
How well we seal draughts. Hatch sealing with Draughtex. Floorboard gaps sealed. CWI bead fills cavity voids. Typical reduction: 30–40%.
Acoustic Rw
Sound reduction in decibels. Standard wall: 35dB. Our acoustic system with resilient bars and SoundBloc: 42dB — enough to mute a drum kit.