How do we ensure sustainable buildings perform as intended? The performance gap between predicted and actual energy use in new homes has been identified as a key problem by government and industry experts. This updated edition is an illustrated practical design guide to delivering better energy performance in all types of new build homes. It introduces readers to the concept of the performance gap and highlights clear issues and solutions to help architects improve their detailing at design stage. The book: Features annotated details with photos taken from live construction sites Includes accessible practical guidance for busy practitioners Highlights how to boost the construction quality and performance of new homes Promotes the case for more architect supervision throughout the construction process. A new chapter features innovative, low-carbon building methods, including hempcrete blocks, clay blocks and straw bales. All information has been updated to reflect the latest data with fresh details and technologies.