New Initiative to Roll Out Ultra-Low Energy Retrofit Homes

Wetherby Building Systems Ltd have joined forces with leading energy and services specialists EQUANS ( EQUANS is an autonomous business within ENGIE Group) to transform post war non-traditional homes with extensive retrofit measures. The “fabric first” approach has transformed the properties into low maintenance, net zero carbon homes with the help of their insulated render systems.

This initiative comes as part of a wider acknowledgment to tackle climate change and reduce greenhouse gas emissions by 2050. UK households account for more than a quarter of the entire UK CO2 emissions with half the market achieving an EPC rating of D or less so attention has been drawn to design and deliver a programme that will not only lift residents out of fuel poverty but improve environmental performances throughout the home to greatly reduce carbon emissions and improve air quality.

Sutton Housing Partnership (SHP) received capital funding to undergo a programme of works to retrofit up to 100 homes in the London Borough of Sutton. SHP enlisted EQUANS to deliver the first of its kind pilot scheme which will see eight non-traditional unity homes undergo a transformation to achieve a net zero energy goal. Wetherby were approached to provide a suitable external wall insulation system for the façade aspect, which could help contribute in achieving the net zero energy goal.

Unity homes were produced after the war to address the severe housing shortage at the time and due to the lack of readily available building materials or skilled tradesmen many of these homes were constructed with precast reinforced concrete (PRC). However, since very little consideration was given to the structural integrity or insulation content of these homes, many were considered defective under the housing defects legislation in the 1980’s meaning thermal efficiency is now in desperate need of improvement.

EQUANS is utilising it’s whole house retrofit model, Engie Zero for this pilot scheme which has derived from the Energiesprong UK performance standard. Energiesprong is a ground-breaking whole-house renovation approach, pioneered in the Netherlands. It upgrades a home with innovative energy-saving and energy-generating measures, which include new highly insulated outside walls and windows, a solar roof, and a modern heating system.

The energy efficiency measures delivered by Engie for SHP will include Wetherby’s A1 external wall insulation system. Wetherby’s A1 EWI system incorporates a non-combustible stone wool insulation, reinforcing mesh and basecoat to achieve the highest possible European fire classification to the BS EN 13501-1 standard. The long-term compressive strength and high impact resistance of Wetherby’s A1 system will provide maximum thermal efficiency for the home owner which will play a huge part in contributing to the net zero carbon target by dramatically reducing their energy bills and creating significantly warmer homes. The system also benefits from excellent acoustic performance making it ideal for absorbing and regulating the noise in the residential area. Due to its non-combustibility, it will provide the residents with superior fire protection giving them piece of mind that they can feel safe and secure in their homes.

The system will be finished with Wetherby’s Mineral Render and Silicone Paint providing excellent breathability and giving the aesthetic a much-needed contemporary new look whilst keeping them in line with the surrounding community.

Steve Tucker, Managing Director of Sutton Housing Partnership, said: “It’s fantastic that our residents will benefit from lower energy bills, warmer homes and a more sustainable future, as a result of this funding.  We’re very proud to be working towards a carbon neutral borough and supporting Sutton Council in its ambitious plans to tackle the climate emergency.”

James Cook, Divisional Director for ENGIE UK & Ireland, said: “This is a commendable venture from the Mayor of London, Sutton Housing Partnership and Sutton Council.  The climate emergency remains the single biggest threat we face and London’s existing buildings are responsible for nearly 80 per cent of city’s CO2 emissions – so investment in retrofitting existing stock is paramount.”