With a focus on maximising the fabric performance of an existing building, the measures listed can help reduce energy bills by up to 65% (see *), and reduce the EPC rating of a house from E to B, whilst avoiding risks such as surface condensation.
There are 20 Standard Construction Drawings available to download for free on Sustainable Building Solutions’ (SBS) website. The drawings detail how to retrofit an existing building to maximise the performance of the fabric using standard building materials. The details include five different wall finishes plus solutions for ground floor living, habitable and non-habitable roof spaces.
By using the retrofit drawings, the building specialist claims, substantial savings can be made to the annual costs of heating a building. The BRE* independently modelled the drawings and calculated that the annual energy costs of a building can be reduced by 65% by following these details in conjunction with a boiler change and the removal of secondary heating in the front room. In addition the Energy Performance Certificate (EPC) rating could be improved from band E to band B.
The process of modelling the drawings allowed SBS to tackle the key issue of surface condensation which has historically been a barrier to increased energy efficiency, particularly in properties fitted with external or internal wall insulation.
Lee Jackson, head of technical at SBS, said: “Added insulation can often have a negative impact on thermal bridging, increasing the amount of condensation in the home. We took this into account so the drawings not only ensure a warmer building, but one that doesn’t suffer from issues that commonly occur as insulation increases.”
Paul Joyner, director of SBS, added: “It is incredibly important to get the fabric of a building right, as it is a lot more permanent than renewable energy products that can be removed or updated if needed. Getting it right is also essential if homeowners are going to get the most out of the Green Deal.”