Technical Booklet E Fire Safety·Page 174·7.2
Fire Safety Information for Existing Buildings Subject to Work
For existing relevant premises or buildings with flats undergoing extension or alteration, fire safety information should only address the work done and its impact on the building's fire safety strategy.
For existing buildings which are relevant premises or buildings containing one or more flats, subject to extension and/or alteration work, the information required should only relate to the work involved where it has an impact on the fire safety strategy of the building.
Source — /Users/richardhill/Documents/planning-arch-project/data/documents/regional/Technical Booklet E - Fire Safety.pdf