Parking Panacea

The continued growth of urban renewal and mass-transit projects has placed an increase importance on parking. Mixed-use and transit-oriented developments in mid- and large-size cities across the nation are drawing more people into dense, high-traffic environments, creating a demand for parking garages.

The mixed-use nature of many of these revitalization efforts, however, has changed the way cities and developers (and even drivers) view parking garages. Clients are not only interested in squeezing as many cars as possible into a garage, but are asking Building Teams to create durable structures that blend with the streetscape, maximize revenue, meet parking demand for multiple venues, and provide safe and efficient ingress and egress for drivers — all the while sticking to a budget that is "often the first to be cut," says Mary Smith, SVP and director of parking consulting for Walker Parking Consultants, Elgin, Ill.

Architectural enhancement is often the first thing to go. Dressing up garages with precast panels, brickwork, glass, and metal detailing is costly, and there's often limited room in the budget for such articulation. It requires teams to carefully select façade materials and detailing, and even consider cutting costs in other areas of the project.

"I've had an amazing number of clients that have asked us to be a little more cost effective in other areas, such as structurally, so they can keep the architectural enhancements," says Smith.

To help offset costs and maintain activity at the street level, more developers are incorporating restaurants, offices, retail, residential, and even entertainment facilities within or above parking structures. Firms are also looking to maximize the use of available parking spaces by planning for shared uses — for example, office traffic during the day and entertainment patrons at night.

"The land value and cost of development is so high many times that developers are looking to maximize land use and revenue," says Dilip Nandwana, president of International Parking Design, Los Angeles. "Parking by itself is not very cost-beneficial, so by incorporating other elements it makes the project much more palatable."

Imagine driving into a parking garage with no gates to pass and no tickets to snatch. Simply follow the electronic signage to the closest available space. When you exit your vehicle, you notice that the garage is much brighter and whiter than the standard garage, with flat floors (that's right, no annoying sloped floors to walk up and down) and a clear view to the nearest stair/elevator tower. To pay for this space, simply pull out your cell phone and dial the number posted on the garage wall.

This is the parking garage of the future, and it's closer to reality than you may think, thanks to new technologies and more architectural forethought.

Many airports, for instance, have begun to install parking availability displays that report the number of unoccupied spaces on each level of a garage. "It helps people make better decisions," says Smith. "If there's only two spaces on level two, but 1,000 on level four, then they'll go straight to four."

Smith says the next step may be automated electronic guidance systems that, through a series of signs and arrows, direct drivers to the closest available space. The technology has been available for more than a decade (Smith evaluated the system for a Disney parking garage in 1991), but has been slow to catch on in the U.S. due to cost.

The benefits of such a system, however, may soon outweigh additional upfront costs, especially for garages in dense, urban environments and other high-traffic areas. The technology is not only convenient for the drivers, but also maximizes revenue by squeezing cars into every remaining space. Building Teams can also use the technology to maximize the number of parking stalls in a structure by eliminating certain circulation aisles. A parking garage at Munich Airport, for instance, is designed with a series of dead-end, two-way parking aisles stemming from a central aisle. "You just follow the arrows and turn down the aisle that has spaces," says Smith. "There's no need to drive up and down aisles."

Smith says an airport client in the U.S. is considering a similar approach for a short-term parking structure, weighing the cost of the system against the gain in parking spaces per square foot and a possible reduction in construction costs. "They're talking about using U-turns instead of dead-ends," she says.

"Pay-by-foot" design schemes — where patrons pay for the space when returning to the garage via automatic teller machines located in each entrance — have also become popular. This scheme can reduce staff size and is a more secure method of collecting revenue, because it eliminates human transactions. "Any time people touch money or credit cards there's a risk of a loss, either to the patron or the business," says Smith.

Smith predicts payment schemes that incorporate credit card transactions at the gate or that eliminate credit cards and cash altogether (e.g., toll tag technology or pay by cell phone) will eventually surpass pay-by-foot in the U.S.

The days of the dark and dingy parking garage are over, says Smith. Most clients are concerned with safety and security and are asking design teams to come up with solutions that won't break the bank.

Smith is designing garages with higher floor-to-floor heights and "significantly fewer" columns than 10 years ago, which "opens up the space and lets you see across the floor." Advancements in precast manufacturing have enabled designers to specify larger precast pieces, allowing for 45-foot bays today, versus 24-foot bays in the past, says Smith. This approach reduces the number of pieces in a precast deck, making it more cost effective.

More clients are also opting for flat-floor structures with express ramps over traditional sloped-floor designs, even though that often results in fewer stalls per square foot, says Smith. Flat-floor garages are common at airports, retail, entertainment venues, where clients are concerned with improved security, faster circulation, and better wayfinding.

For a small premium, Building Teams can replace the traditional, dingy, yellowish high-pressure sodium light fixtures with bright-white metal-halide or fluorescent fixtures that better illuminate the space. Smith says many metal-halide and fluorescent vendors now offer outdoor-friendly models that operate in cold climates.

"These may not be as cost effective as high-pressure sodium, but the white light will make people feel more secure than the yellowish light that tends to distort certain color cars and creates sort of a dingy atmosphere," says Smith.

Staining the concrete white is another cost-effective way to brighten garage space and improve security, according to Greg Stidham, structural department manager with URS Corp.'s Columbus, Ohio, office. "Sometimes too much light in a facility creates dark spots," he says. "Staining the concrete can help with that."

Stidham adds that glass-enclosed stair/elevator towers, daylight, security cameras, and emergency calls buttons have become commonplace on parking structure projects. Securing the ground-floor level and eliminating hidden corners and spaces, such as under open stairs, are also a must.

A greater number of clients are also willing to spend a premium for structural durability, says Erich Martz, operations manager for structures with HNTB Architecture Inc., Kansas City, Mo. Martz says at least half of the firm's clients will consider spending anywhere from 2–5% more for formulation and testing of concrete mixtures and designs that will ensure a 50–75-year lifespan, especially to fight against one of concrete's most formidable enemies: road salt.

"Road salt that gets dragged into parking garages from cars eventually infiltrates into the concrete," says Martz. "Chlorides in the salt cause corrosion of the steel rebar and spalling of the concrete."

Building Teams can extend the life of the concrete by employing any number of corrosion-protection systems, including the use of low-permeability concretes (which incorporate fly ash, silica fume, etc.), corrosion-inhibiting admixtures (e.g., calcium nitrate), epoxy-coated steel reinforcement, corrosion-resistant steel or non-ferrous reinforcement, application of waterproofing membranes or sealants, and cathodic protection.

Martz says new software tools, such as Stadium from Material Service Life, Monroeville, Pa., and Life 365 from the American Concrete Institute, Farmington Hills, Mich., can help engineers determine the service life and life cycle costs (i.e., repair and maintenance) of various concrete formulations when exposed to different environmental and chemical influences.

"Using these programs, we can show the owner that it's typically more economical to spend a little more up front and less on maintenance over the life of the garage," he says.

Martz, who is also involved in American Concrete Institute's parking structures committee, says providing both proper slope for drainage and a sufficient number of expansion joints are also key components of durability.

"I walk into many garages that don't have any slopes to the drains, so the water does not drain properly," he says. "This is a basic principle, but many engineers in the past did not put much thought into it. It's amazing how much water cars can drag in on a rainy or snowy day."