Synergy News & Blog: News
Knaphill Bungalows – a shining example of whole-house retrofit in the UK
The UK has some of the oldest and poorly insulated homes in Western Europe. Around 18 million homes are estimated to have an EPC rating of D or lower (Rightmove analysis) leading to cold and damp conditions and energy leaks that cause substantial bills.
Adopting a retrofit-first approach to decarbonating the UK housing stock will be essential in meeting net-zero carbon targets.
When viable, upgrading existing buildings already in place will have a range of benefits, from reducing construction waste, carbon emissions and energy bills, to creating better standards of living for residents.
Case Study: Knaphill Bungalows
Synergy was appointed by Thameswey Developments to provide cost consultancy services on the retrofit of two bungalows in Woking to help improve their low carbon credentials. We worked on the project with contractors and brick manufacturers Wienerberger.
The project is an exemplar model of a ‘whole-house’ retrofit approach to creating the most optimum energy efficient property. Extensive upgrades have included innovative construction solutions combined with sustainable technologies to significantly reduce emissions and running costs.
One of the most significant structural improvements involves the construction of a new outer brick skin surrounding the bungalows, which is equivalent to ‘throwing a duvet’ around the properties. With existing cavity walls in place, this has upgraded the dwellings with a thermally efficient triple brick skin.
Roof coverings have been replaced along with the installation of new insulation. High performing double glazing has been implemented throughout and air permeable membranes used in ceilings and floors will reduce energy loss.
In-roof solar PV systems installed have enabled the properties to generate and store their own renewable energy. Efficient heating is achieved through air source heat pumps and underfloor heating.
The previous EPC ratings E and F have been drastically improved, with the properties boasting new A and B ratings. In addition, heating bills have been reduced from nearly £2000 to a fraction of that amount.
It is estimated that most of our existing housing stock will still be standing in 2050. This project demonstrates the innovative retrofit solutions that will need to be applied to millions of homes across the UK.
