how big is 10 downing street

10 Downing Street is approximately 6,000 square feet in total area, spread over multiple floors including a basement. The building contains around 100 rooms, which include the Prime Minister's private residence, offices, conference rooms, reception areas, sitting and dining rooms. It also has a notable garden area of about 0.5 acres (around 2,000 square meters) at the rear. Originally, it was three houses joined into one, forming this famous Georgian-style terraced building.