This book tells how to insulate your house fully, not just the loft, and together with such things as solar panels get it close to net zero. Owner-occupiers in a street form a club and appoint construction professionals. They prepare a scheme and detail it. Surveys and assessments are carried out by scanning externally and internally as well as in traditional ways. Insurers are part of the scheme, covering risks and providing warranties. A builder wins the job and their costs are met by a mortgage from a retrofit building society. The cost of energy saved pays for the work. Cracking and other deficiencies and previous ill-advised alterations must first be rectified. The builder then fits external wall insulation in the upper parts of the house, and internal wall insulation at ground storey. Owners remain resident, surrendering rooms by the working day for the latter. Other necessary things are done, insurers allowing for the unexpected. There will be universities of retrofit. Finally, an Enhanced Retrofit Passport certifies the house owners into the 22nd century are reassured. The book has 15 appendices.