No other town we work in has this range. Within a mile of Evanston’s downtown you will find 1890s frame Victorians, brick foursquares from the 1910s, the courtyard apartment buildings of the 1920s that are now almost all condominiums, and blocks of Chicago-style bungalows running west and south. Add the 1950s ranches at the north-west edge and you have five different bathrooms with five different answers.
The common thread is age. Most of the stock predates the Second World War, which means the room is small, the waste stack is cast iron, and the supply may still be galvanised steel. What changes from house to house is whether you own the walls.
In a single-family house the constraint is structural; in a condo or a converted flat it is procedural. A detached Victorian will let us take space from a closet and move a drain within the joist bay. A third-floor condo will not let us start until the board has the scope, the insurance certificate and the working hours in writing. Both are ordinary. They just need starting at different times.