The Longman Dictionary says "baker's" and "barber's" could mean their respective establishments in British English. If so, is the following OK?
There is a two-storey barber's across the street.
English Language Learners Stack Exchange is a question and answer site for speakers of other languages learning English. It only takes a minute to sign up.Sign up to join this community
Sample: There is a two-storey barber's across the street.
No, but not due to grammar. Barber shops and bakeries are on the ground or first floor of a building.
They may be located on the ground or first floor of a two-storey building but they do not constitute a two-storey building.
I was at the barber's [shop] across the street this morning.
By the way, there is no difference with AmE in these cases.
We Brits do this with a lot of professions which are also establishments.
Butcher's, baker's, candlestick maker's*, grocer's, doctor's, dentist's, tobacconist's, cobbler's, barber's, hairdresser's… the list goes on.
We would rarely add 'shop' to this. These can easily stand alone.
"I'm going to the doctor's next Tuesday" really describes the visit to the establishment rather than the person, though without further qualification one would expect their purpose would be to see the doctor.
*Just to complete the set with reference to the old nursery rhyme, rub-a-dub-dub ;)