Vic’s advice on how to build a “Greener” extension featured in Self Build & Design magazine
Wednesday 23 June, 2010
Vic has been giving advice on the best ways to ensure house extensions are eco-freindly. Please see the following article published in the latest Self Build & Design magazine.
“Top tips for a greener extension Award winning architect Vic Johnson offers some practical advice on how to make your extension more eco-friendly.
Orientation. Many people have suffered because they built south-facing conservatories, which had to be subsequently removed because they absorbed too much direct solar gain. If you have to build on the south of your property, think about controlling illumination and proper thermal design.
Waste. Consider what you are removing in order to build your extension. Can excavated ground/earth be re-used on site rather than being removed and dumped elsewhere (expensive and not ecologically sound)? Earth mounding can be a way of creating thermal stability but bear in mind it may not be that applicable on flat sites.
Thermal mass. Think about whether you wish to create a high thermal mass extension, which will take a while to warm up but will retain the heat, or a light thermal mass structure which will be quick to warm up but will also cool down relatively quickly. The structure of the existing building should always complement and affect the form of extension.
Planning. Remember that despite your high ideals and desires for an eco- orientated extension, the planning authorities often have other ideas. Anything ‘special’ usually involves a bit more discussion to get a positive result. A significant and convincing rationale usually has to be concocted to get them on board. Remember also that an objection will mean that they could actually decide against the application without going to committee (on delegated powers). Reference should be made to the appropriate PPGs and planning policies.
Existing structure. Thoroughly investigate the existing building and particularly the structure and services you are connecting to. It may be beneficial to upgrade existing systems to a more efficient level befitting both existing and new build structures.
Materials. Try and use indigenous materials local to the site areas. Brown roof systems provide a home to local flora and fauna, green roofing may not be as ‘green’ as the area if your sedum roof arrives from Norfolk and your project is in Cornwall!
Structure. Don’t overlook local suppliers. Your local timber frame manufacturer may be able to supply that difficult roof profile; why not ask him before going further afield? It all helps keep that budget on track.”