New development may be skidding to a halt, but the need to improve existing buildings is just as important as ever. Building looks at the winner and runners-up of the prize for refurbishment at the Sustainability Awards
Making existing buildings more energy efficient is one of the biggest challenges facing occupiers, government and the industry today. Just over 1% of the built environment is replaced each year, which means reducing carbon emissions can only be achieved by significantly improving building that are already there. This is why two years ago Building launched its 99% campaign, which called for action to improve existing stock.
But this is easier said than done. Upping the energy performance of existing buildings is particularly difficult because many are very leaky, barely insulated, single glazed and burdened by clapped out services. The archaic construction methods originally used for many of them makes updating even more tricky. Adding insulation to solid walls, for example, either makes internal spaces smaller or changes the external appearance of a building.
The Building 99% Campaign award for refurbishment recognises teams that successfully overcame these challenges to produce energy-efficient buildings fit for the 21st century. Here we present the six entries that made it onto our shortlist including the winner Axis Design.
Axis Design, EcoterraceThere is a lot of Victorian terraced housing around, and its poor energy performance makes finding ways of improving it particularly pressing. Architect Axis Design teamed up with Staffordshire Housing Association and two councils to do just that. The team took a row of six Victorian homes and improved their energy performance from a rock bottom EPC rating of G up to an A. Common methods were uses, such as adding insulation in the walls, under the floor and in the roof, high-performance windows and a high-efficiency heating system. What was most radical was that at the back, single-storey additions were replaced by sunspaces intended to maximise solar gain and improve daylight levels inside. These improvements have cut energy bills from £800-1,200 to £200.
3D Reid, Marks & Spencer storeSupermarkets have made a lot of noise about greening their property portfolios, which mainly means upgrading existing buildings.
To that end, retail giant Marks & Spencer engaged architect 3D Reid to upgrade a 70-year-old store in Bournemouth. Improvements to the building fabric included adding glazed lobbies and insulated display windows to the building to improve thermal performance and airtightness. A green roof was installed to increase biodiversity on the site.
A-rated materials from the BRE Green Guide to Specification were used where possible and water-saving taps and toilets have also been specified. The result was that the building, which uses 25% less energy than before, achieved a BREEAM “very good” rating.
Tentigo Design, zero-carbon loft conversionThe energy performance of an existing Victorian terraced house has been significantly enhanced by the addition of a zero-carbon loft extension. Its specification is as radical as its appearance; it has well-insulated fabric, high performance glazing, a mechanical ventilation system with heat recovery, and phase change materials in the walls and ceilings to give it the same thermal mass as 90mm of concrete. It also has a wind turbine and greywater recycling facilities.
Because the loft extension increases the floor area by 50%, this means total energy and water use per square metre in the building should be cut by half. The project will be monitored to see if it delivers on these predictions.