PPS 7 (Addendum): Residential Extensions and Alterations
Annex A: Context and Design: Sustainable Design
A21 The Department wishes to promote and encourage a sustainable approach to development. The extension or alteration to a residential property can provide the opportunity to improve its sustainability in terms of incorporating energy efficiency measures, renewable energy technologies, the re-use of existing materials and measures to enhance biodiversity. For example, additional insulation and rainwater recycling using water butts.
A22 Where existing walls are being demolished or roofs altered, existing materials can often be salvaged and re-used, which will benefit the visual appearance of the new work and its integration with the existing property. Solar thermal panels that produce hot water and photovoltaic (PV) panels that produce electricity can be installed in roofs. PV tiles are now available that look like traditional tile and slate roofs, allowing the installation of these systems to be sensitive to the character, colour and style of the existing roof. Green or ‘living’ roofs can further benefit the environment by enhancing biodiversity and providing high standards of insulation. Extensions also provide the opportunity to consider the provision of additional landscaping to soften the impact of such works (see also paragraphs A39 – A40).