The Government’s Retrofit for the Future programme aims to identify the challenges of refurbishing our existing housing stock and discover solutions. Greenbuild News visits Byron Square, one of the first schemes to be completed.
Newbuild is easy, relatively speaking, when it comes to creating low-carbon housing. Refurbishing homes of varying design, construction method and quality is not so straightforward. The facts and figures concerning existing houses that need upgrading in order to meet the carbon emissions reduction targets are challenging: there is a national target to reduce emissions by 80% by 2050 and, currently, 27% of the UK’s carbon emissions comes from housing. This needs to be cut by 29% over the next ten years if the Government is going to meet these targets.
Identifying and overcoming the many challenges of sustainable refurbishment are the reasons behind the Technology Strategy Board’s (TSB) Retrofit for the Future programme, which was launched in 2009. It was a competition open to companies and organisations, including local authorities, who could apply for funding to retrofit social housing stock, using whole-house solutions to improve the performance of a property and make significant reductions in its carbon emissions.
Number 31 Byron Square in Trumpington, Cambridgeshire, is the site of one of the first Retrofit for the Future projects to be finished. The project was carried out by PRP Architects in conjunction with Cambridge City Council (which owns the property) and contractor Hill Partnerships. The three-bedroom, semi-detached house is a steel-framed, 1940s BISF (British Iron and Steel Federation) property – and there are around 36,000 of this type around the country, so the lessons learned could have a huge impact on further refurbishment projects. Sara Garnham, business development director at Hill Partnerships adds: “In completing these feasibility projects with PRP it is clear that the skills and expertise to deliver refurbished homes is as vital as understanding of the new products and technologies. Handling NASA-developed insulation correctly is as much a requirement as dealing with the unexpected services routing that you find in older properties. Lessons learnt from this project give us an excellent base to move forward with other projects.”
The house has a floor area of 88m 2, which meant the project team were aiming to achieve CO 2 emissions of 1,500kg a year. The Retrofit for the Future targets were linked to the Climate Change Act and, for the purpose of this competition, a target of 17kg of CO 2/m 2/yr was set. A target for space heating demand was added (to ensure the teams could not ignore the building fabric) at 120kWh/m 2/yr. At Byron Square this is a target of 10,600 kWh/yr (or approximately a £440 heating bill). Even appliances such as hairdryers and TVs, that SAP does not include, were added to the energy equation.
Sam Griggs, home energy officer at Cambridge City Council explains how the house – and its tenants, the Kent family – were picked for the project: “We held a competition for the tenants of eligible houses to choose which one we would put forward for the project. We wanted a family that would be engaged with the project and that would benefit from reduced energy bills.” The Kent family of two adults and three children – aged between four and 16– stayed in the house throughout the retrofit project, which wasn’t completely straightforward, as Griggs explains: “We didn’t envisage the amount of disruption and having a four-year-old on a building site is not ideal. But one advantage of the family being on site is that they could learn about the new technologies as they were being installed.” Luckily the work was carried out during a spell of gorgeous weather in early summer, so the Kents could spend a lot of time in the garden.
The retrofit solution at Byron Square maximises the thermal performance of the fabric and significantly reduces the reliance on fossil fuels. Andrew Mellor, PRP’s environmental director, adds: “PRP’s aim was to develop an energy reduction solution that was innovative yet replicable and economically viable.”
The retrofit includes the following solutions:
• photovoltaics and solar thermal panels in matching frames;
• aerogel insulated drylining;
• triple glazed windows with thermal control layer;
• full LED lighting;
• flue gas heat recovery;
• waste water heat recovery system;
• low-energy decentralised whole house ventilation;
• energy display system – interactive touch screen interface for education and awareness.
The most important part of the Retrofit for the Future project was education – finding out how effective different solutions are, how they can be incorporated into different buildings and how we can roll-out these solutions to really make an impact on cutting carbon and energy bills. Mellor elaborates: “It’s important that we try to resolve the lessons learnt through 31 Byron Square as we need to start the mass retrofit revolution very soon. Early consideration on how to solve delivery issues along with funding, incentives, resident awareness and quality control is imperative. PRP recommend a ‘Retrofit Roadmap’ to ensure that industry knowledge is shared and research is not wasted.”
Key lessons, barriers and recommendations from 31 Byron Square
• The UK supply chain needs to be developed
• The length of time for projects need to decrease and residents need to be properly informed on how the process will impact them
• Better survey data on properties is required prior to commencing work
• Improved guidance and training for planning authorities is required
• Contractors need more experience to accurately price works
• Quality of retrofit delivery needs consideration along with effective warranty provision