Parking structures must accommodate many vehicles efficiently while providing safe, convenient access. Structural systems supporting large floor areas include post-tensioned concrete, steel framing, or hybrid systems. Column spacing typically 60 x 60 feet provides efficient parking layout. Ramp design provides access with acceptable grades (maximum 8 percent). Circular ramps or linear ramps accommodate different configurations. Turning radius must accommodate large vehicles. Ventilation removes exhaust gases. Natural ventilation through openings may be adequate. Mechanical ventilation with CO detection and monitoring ensures air quality. Level changes between floors must accommodate vehicle suspension. Slopes of 2 percent or less prevent scraping. Lighting provides adequate visibility for safety. Emergency lighting operates if main power fails. Pavement markings define spaces and traffic lanes. Staining resistance of pavement prevents cosmetic degradation. Anti-icing treatments prevent ice formation in cold climates. Drainage systems manage stormwater and prevent water pooling. Proper pitch directs water to drains. Durability of the structure requires good maintenance. Pavement seal-coating and overlay extend life. Structural repairs address spalling concrete or rusted reinforcement.