Quote:
"Coronation Street was built in 1902, opposite Hardcastle's Mill and the Glad Tidings Mission Hall. No.9 had an identical configuration to the six other residential houses in the row: on the ground floor, a front parlour, hallway, back room and scullery, three bedrooms on the first floor, and an outside toilet and coal hole in the yard".
Source:
https://coronationstreet.fandom.com/wiki/9_Coronation_Street
However that source doesn't explain where the bathroom has come from, although it does indirectly confirm that it exists. ("In 1991, the water went off in Coronation Street while Vera was running a bath"). In all of the old terraced houses I've known, the outside lavvie has been replaced by a bathroom at the expense of losing a bedroom, so that would only leave two bedrooms in use.
(Erm, why am I answering this question? I've not seen Coronation Street since the days when Elsie Tanner was battling it out with Ena Sharples!)