Glidevale shows how to foil heat loss
A reduction of at least 80% in heat flow through walls, roofs, ceilings and walls is claimed for Glidevale’s Protect VC Foil membrane compared with conventional vapour-control barriers. Installed in timber-frame walls with a 20 mm airspace, the behaviour of the foil in reflecting heat back into the building is said to be equivalent to at least 34 mm of mineral wool. The foil is secured to the inner face of the insulation slabs and has the added benefit of creating a service cavity on the warm side of the insulation. Glidevale uses the BRE U-value calculator software for thermal performance. In walls with a 20 mm airspace, Protect VC Foil reduces heat flow by 63% compared to a wall with a similar size unventilated airspace. In roofs and ceilings with a 13 mm airspace, a 50% improvement is achieved. In floors with a 50 mm airspace, a reduction in heat flow of 81% is calculated.