Sika has worked with Swansea Council to transform 14 prefabricated 1970s homes into warmer, more energy-efficient properties as part of a comprehensive retrofit programme.
Located in the hillside village of Craig Cefn Parc in the Swansea Valley, the semi-detached Resiform houses were originally designed as low-cost temporary housing. Their lightweight timber frames, resin-fibreglass external cladding and thin mineral wool insulation provided limited thermal performance.
Swansea Council’s goal was to create warmer, lower-carbon homes while residents remained in occupation. The project, supported by the Welsh Government-funded Optimised Retrofit Programme, also extended fabric improvements to neighbouring privately owned properties.
A fabric-first approach saw Sika’s Parextherm external wall insulation (EWI) system installed alongside new roofs, windows and doors, solar PV, battery storage and air source heat pumps.
Applied directly to the timber frames, the EWI build-up incorporated expanded polystyrene boards mechanically fixed to oriented strand board, followed by a flexible weatherproof base coat with reinforcement mesh. A hand-applied dry-dash aggregate in alpine blue completed the façade, providing a refreshed finish designed to withstand the exposed hillside conditions.
Keeping residents in their homes presented another challenge. Temporary heating was required during the switch from oil heating to air source heat pumps, while regular communication helped address initial concerns and minimise disruption.
The completed external walls now achieve a U-value of 0.18 W/m²K, while the renewable technologies have removed the homes’ reliance on oil.
Stuart Lloyd, Site Manager for Swansea Council, said: “This was never going to be a standard upgrade.” He added: “Working closely with Sika, we effectively rebuilt the external envelope around these homes, overcoming constraints to deliver a technically robust solution that has genuinely changed how residents live in their homes.”