The J. Edgar Hoover Building has of internal space, numerous amenities, and a special, secure system of elevators and corridors to keep public tours separate from the rest of the building. The building has three floors below-ground, and an underground parking garage. The structure is eight stories high on the Pennsylvania Avenue NW side, and 11 stories high on the E Street NW side. Two wings connect the two main buildings, forming an open-air, trapezoidal courtyard. The exterior is buff-colored precast and cast-in-place concrete with repetitive, square, bronze-tinted windows set deep in concrete frames.