60s SEMI-DETACHED RETROFIT & EXTENSION
Project Details
Status: Completed 2024
Location: Surrey
Type: Retrofit + Extension
Construction: Timber frame extension, woodfibre EWI
Description
We're delighted to see the completion of this project to externally insulate and extend this semi-detached brick house in Surrey. The existing property had only minor alterations since it was built and the brick garage was in poor structural condition. This created the opportunity to bring the house into the 21st Century by wrapping the walls in rigid woodfibre insulation, replacing the loft insulation with several layers of flexible natural insulation, upgrading the heating system, and remodelling the ground floor with a new insulated porch, a glazed timber frame extension to make the most of excellent views to the rear, and replacing the old brick garage with a new timber frame garage and utility.
As the house has only had minor alterations and there were many similarly constructed houses from the 1960s-80s it is a useful case study project for exploring ways to retrofit and modernise a late 20th C. house using natural materials. As with all our project we aimed to minimise the embodied carbon of the work, this was achieved by using structural timber to support the first floor walls rather than steel, rubble trench foundations with brick plinth walls on a lime screed bedding rather than concrete strip foundations, and a limecrete floor insulated with compacted foamglas aggregate for the extensions rather than a concrete slab on petrochemical based insulation.