Home Extension Design (second edition) and Taste: A cultural history of the home interior, are two of the books curated within the Royal Institute of British Architects (RIBA) home inspiration collection.
Written by seasoned self-build advisor Julian Owen, Home Extension Design is full of practical tips and top level advice for those embarking on such a project, including walking you through all the stages from concept to completion. It’s really useful as a homeowner’s guide, touching on the watchpoints you need to be aware of.
Drew Plunkett’s Taste, meanwhile, is a very detailed and well researched guide into the origins of architectural and domestic styles.
However know that both guides are for Britain and aimed at that market so the regulations discussed are for England and Wales, for example.