All savings are based on space and water heating in a typical gas central heated property, using an average gas price of 4.21p/kWh correct as of July 2014. Savings are the modelled differences in heating running costs between typical historic homes (sourced from SAP 2009) and modern Barratt Homes (sourced from Barratt Homes), assuming the dimensions remain the same. Dimensions are based on the Holden (detached house), Barwick (Semi-detached house), Tiverton (mid-terrace house) and Foxton (flat) Barratt Home properties. Please note that savings may vary with different historical home configurations, construction type and building orientation which has an effect upon heating requirements. This information should only be used as a guide.