The UK's first rural affordable housing accredited Passivhaus scheme is complete – and the housing association behind the project has cited below-slab insulation as key to achieving its very high levels of energy efficiency.

The scheme in Wimbish, Essex, features Dow Building Solutions' FLOORMATE 300-A STYROFOAM insulation as a continuous layer beneath the concrete floor slabs to help prevent thermal bridging.

According to Hastoe Housing Association, "by creating an envelope of insulation outside the waterproofing envelope, FLOORMATE 300-A has helped to minimise heat loss in the homes, a key feature of – but not exclusive to – Passivhaus".


"We were pleased to learn that its compressive strength and moisture resistance make it a durable product, suitable for our rural homes that will be lived in by future generations for many years to come," the Association continued.

FLOORMATE 300-A is available in a range of thicknesses: 50mm, 75mm, 100mm, 125mm and 150mm, and has a design load of 130 kN/m2. The material is manufactured using CO2 as a blowing agent giving it a Global Warming Potential (GWP) of less than five.

For more details on FLOORMATE 300-A and other insulation products, contact Dow Building Solutions on FKLMAIL@dow.com or visit www.styrofoam.co.uk