The previously linked to Part M Regs document is no longer current. The latest is: https://www.gov.uk/government/uploa...BR_PDF_AD_M1_2015_with_2016_amendments_V3.pdf
Cat M4(1) pages 4-9 is most applicable. Page 7 shows the information you require on corridor widths to habitable rooms (essentially wider doors enable narrower corridors). However does not apply to extensions.
This is the book to buy: https://www.amazon.co.uk/Architects-Pocket-Book-Routledge-Books/dp/1138643998/ref=dp_ob_title_bk
Cat M4(1) pages 4-9 is most applicable. Page 7 shows the information you require on corridor widths to habitable rooms (essentially wider doors enable narrower corridors). However does not apply to extensions.
This is the book to buy: https://www.amazon.co.uk/Architects-Pocket-Book-Routledge-Books/dp/1138643998/ref=dp_ob_title_bk
