A historic house generally meets several criteria before being listed by an official body as "historic." Generally the building is at least a certain age, depending on the rules for the individual list. A second factor is that the building be in recognizably the same form as when it became historic.
Madame Tussauds London
The Regent's Park
The Regent's Park
The Sherlock Holmes Museum
The Metropolitan Bar - JD Wetherspoon
Bill's Baker Street Restaurant
Nando's Baker Street
L'Antica Pizzeria da Michele