SDG has considerable experience with parking structure design. Our projects have included both precast and post-tensioned parking garages. SDG has designed approximately 50 new parking garages since our inception in 1999, with an average of 625 cars each.
SDG understands the design of parking structures must include a cost-effective framing system, a functional layout, and ideally a structural system which requires minimal maintenance over the lifetime of the structure. We’re active in initial project stages to help Owners make decisions on the most-effective system for their project. Precast concrete parking structures are typically the most economical to construct when the garage configuration is not complex due to the use of off-site, plant-produced modular components. However, the competiveness of precast structures can be limited based upon the proximity of the precast manufacturers to the site. Post-tensioned concrete structures are generally competitive when the design requires unique or complex geometry. The type of project will also factor into the design. Underground parking levels and/or a mix of commercial spaces will demand unique framing, which would be more appropriate for a post-tensioned concrete parking structure. Precast garages are often faster to construct as compared to a cast-in-place concrete structure, which requires forming, shoring and reshoring cycles. Precast can also be more favorable during winter construction periods.
Functionality of the garage, from a user’s standpoint, must also be considered in good design. This includes ramps with proper slopes, appropriate drive lane widths and turning radius, good circulation to exit and entry locations, user-friendly stair and elevator locations, and the avoidance or minimization of blind spots in the garage.
For Owners, life-expectancy and long-term maintenance costs of the garage are important. Both post-tensioned cast-in-place concrete parking structures and precast parking structures have advantages and disadvantages. Regardless of the structural system, the use of good details with respect to drainage, proper reinforcing steel cover, the use of joints and appropriate sealants, concrete mix design, etc. is imperative. Post-tensioned concrete parking structures can be designed for extremely long life cycles with minimal maintenance and, if properly designed and constructed, are likely to have lower maintenance costs. Precast parking structures, while having high quality control for the individual precast components, have a propensity for leaking at the joints between members. High quality sealants are specified for use at all joints and should be maintained over the life of the structure. The monolithic nature of post-tensioned structures is also a plus for minimizing leaks.
- TriStar Centennial Medical Center Parking Structure, Nashville, TN (8 levels, 2,800 cars)
- Grandview Medical Center Parking Garage, Birmingham, AL (1 million SF, 3,500 cars)
- Nashville Zoo Parking Structure Vertical Expansion, Nashville, TN (added 1,000 cars for a total of 2,000)
- Methodist Hospital Parking Structure, San Antonio, TX (800 cars)
- Davie Hospital Parking Garage, Davie, FL (7 levels designed to expand to 13)
- Gulch Crossing Parking Garage, Nashville, TN (750 cars)
- City Centre Garage, Jackson, MS (500+ cars)
- Green Hills Mall -Parking Structures, Nashville, TN (300,000+ SF)