Mixed-Use Parking Structure Design

As the number of vehicles continues to increase exponentially around the globe, the need to house them near destinations is creating a design challenge. Besides, a parking lot or facility must provide for efficient and safe passage of the driver and the vehicle. Unfortunately, this is a complex challenge since traffic, engineering and automotive issues associated with the site location must be integrated to come up with the appropriate solution. Therefore, the design of parking facilities requires an integrated approach that involves many professionals.

In most cases, parking has been reduced to building a parking lot or the most minimal stand-alone structure without integrative, human, or aesthetic considerations. As a result, parking has frequently disrupted the existing urban fabric and garnered a poor public perception.

 However, many engineers, planners, and architects are now envisioning and building far more complex, integrated, and aesthetic features to create good parking structure design. More importantly, design and engineering for mixed-use parking are becoming more common, especially as land becomes scarcer in urban settings.

As you would expect though, these changes are affecting the appearance and cost of parking facilities. For that, it’s important to consider these complexities right from the planning phase.

Major changes in integrating parking facilities into mixed-use projects

• Structural framing of the 2nd level

Most stand-alone parking garages are framed with long-span beams to allow for unobstructed parking bays. Unfortunately, while this kind of framing is acceptable for parking, it’s not appropriate for retail space as it will have a relatively high amount of vibration and deflection.

One way to counter this issue of noise and vibration is to use short-span framing with flat slabs. This will improve the success of the mixed-used parking facility as it has proven to be effective in reducing the vibration above the retail space. However, this approach can only be used between the ground & 2nd level, with typical long-span framing structures used above the 2nd floor for efficient parking.

In addition, efficient structural integration is crucial to ensure the maximum functioning of the mixed-use facility. For instance, since the parking facility is usually an exposed structure, its design should withstand every aspect of environmental conditions. On the bright side, there are ideal structural bays that ensure maximum flow of vehicles and number of parking spaces depending on the site and structure. Also, structural design for mixed-use parking facilities can use structural steel, precast concrete, and cast-in-place concrete.

• Floor-to-floor height of the 2nd level

Typically, parking facilities have a floor-to-floor height of about 10.5 – 11.5 ft from the ground to the 2nd level. However, the inclusion of a mixed-use in the facility requires this height to be at least 16 – 19 ft, depending on the mechanical ducting needs and the type of structural framing.

Secondly, the most efficient stand-alone parking facilities use parked-on ramps with a slope of 5 – 6%. So, when the floor-to-floor height of the structure increases by about 5.5 – 7 ft, these parked-on ramps will most likely not work since the facility doesn’t have adequate length to accommodate them.

For instance, if a typical garage ramp is 180 ft long, the length would need to increase by up to 110 ft if the floor height increases by 6.5 ft. This means that the total length of the ramp would need to be 290 ft. Unfortunately, most downtown blocks cannot accommodate such a total ramp length. Therefore, a speed or express ramp will; need to be introduced into the mixed-use parking structure design and engineering, which will affect the framing system and parking efficiency (sq ft per stall).

•  Accommodating trash & delivery

Trash and supply delivery are common everyday services to retail spaces but are not common to stand-alone parking spaces. Therefore, when creating a design for a mixed-use parking facility, you have to consider where the tenants will take their trash out. Also, you have to consider where to store the collection bin for easy access by the local service and where the delivery trucks will park to unload supplies. These issues should be addressed during the initial planning stage to prevent them from taking up valuable parking spaces at the ground level and reducing the drive parking efficiency.

• Mechanical, Electrical & Plumbing design for mixed-use parking facilities

 MEP design can significantly increase the cost of a mixed-use parking garage. For that, it’s important to consider the number and type of retail spaces and how their utilities will be monitored during use when building a mixed-use parking garage. Besides, the need to run ductwork for the HVAC systems is one of the factors that cause the floor-to-floor height for mixed-use parking facilities to increase.

Conclusion

Understanding how a mixed-use parking garage is designed will have a significant impact on the construction cost. Moreover, this will allow you to create an open parking garage, besides other spaces for different use. Alternatively, you can build an open parking garage podium instead of an underground parking garage.

If you’re planning to build a mixed-use parking facility in California, Contact Innodez Design & Engineering. Our engineers will help you undertake the challenging program with retail and parking to ensure the success of your project.