A single-helix configuration is a garage layout in which the parking floors themselves slope, so a driver climbs continuously in one spiral direction, rising one full level with each loop around the building.
In the common two-bay version, each bay rises half a level, and turns at the ends connect them. Inbound and outbound traffic share the same path, and every stall is reached along the way. It is a form of continuous-flow circulation.
Where it fits
- Small and mid-sized garages where every stall should be easy to find on the way up.
- Sites long enough for gentle slopes. Parking floors must stay walkable and comfortable to park on. See ramp slope.
- Operations that can tolerate exiting drivers circulating past parked cars.
Variations
- Double helix. Two interleaved spirals, often one for going up and one for going down, so inbound and outbound traffic separate. See double helix.
- End-to-end and split level. Other ways to climb with flat or partly flat floors. See two-bay end-to-end.
- Express ramps. Large garages add a dedicated ramp so exiting drivers skip the search path. See express ramp.
The Parkonomics view
The single helix turns the whole garage into the ramp, which is efficient until the garage gets big. Past a certain size, the trip from the roof to the street is the reason drivers choose another garage.
Related terms: Double Helix, Continuous-Flow Circulation, Express Ramp, Ramp Slope, Two-Bay End-to-End, Circulation System