by Greg Neiderer, PE, Principal and Director of Restoration, Philadelphia office

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Winter snows are here again, and we wanted to share tips for keeping this winter’s storms uneventful for parking structure owners. Parking decks are typically designed to support both typical snows and cars parked on the roof. So why do we hear of snow-related parking deck collapses in the news?

First, new snow is light, often weighing about 12 pounds per square foot for every foot of depth. And while the specific snow load requirements for parking decks vary by geographic location, most decks are designed for a snow depth greater than 18 inches. Often structures can hold much greater depths of fallen snow, especially when there are few or no cars on the roof. So why do collapses occur?

The most common reason is plowing and piling the snow. Plowing densifies the snow, increasing its weight per cubic foot. Then, this heavier snow is often placed into large piles. It is these concentrated loads, much heavier than cars, that cause problems. Snow removal firms are mostly familiar with slab-on-grade parking lots where big piles are not a problem and often not aware that parking structures are not designed for large piles.

For those parking decks where the roof is at street level with parking levels below the street, less experienced plow operators may not even realize they on a structure. For these decks, weight capacity signage and height barriers to prohibit large vehicles are appropriate.

Snow-related collapses can also occur in structures that are already weakened by significant deterioration. In rare instances, a big blizzard is followed by heavy rains that make the once-light snow suddenly become heavy.

Less of a headline but a much more common for owners is damage done to parking structures by overweight snow removal equipment, causing roof damage leading to early deterioration and unexpected repair costs.

What to do?

Often the best solution in more moderate climates—where temperatures frequently rise above freezing—is to leave the snow alone and wait for it to melt, if you can afford the loss in parking capacity.

If you do need those spaces, be sure to not allow large snow piles and use small equipment to remove the snow from the roof. Remember that parking decks are among the most lightly loaded structures built. They are designed to effectively store cars, not large piles of snow.

Know your structure’s weight limits, know your snow equipment weights, and design snow removal procedures to avoid dangerously heavy loads. You can work with your Walker team during the design process to strengthen the roof above the minimum required loads for more snow removal flexibility. Or, if the structure already exists, you can work with Walker to determine the most cost-effective removal process while staying safe.

Questions?

Call or email Greg Neiderer, PE, who will be happy to discuss any issues with your parking structure, snow-related or otherwise:

610.995.0260
gneiderer@walkerconsultants.com

Watch how Walker Consultants helped Harbor Point Condominium navigate a complicated roof repair project (that ended up turning into a roof replacement!) and see how the expertise of a third-party architect or engineer is invaluable to property managers and owners.

Learn more about the Harbor Point roof replacement project.

Jared Wright, PE, PhD; Dan Johns, PE; and Matt Hunt, PE review causes of structural deterioration in precast double tee parking structures, as well as tried-and-true repairs for these issues.

They also explain the importance of early intervention and lifetime maintenance plans. A 40-year maintenance plan can save $2 for every $1 spent by preventing the need for major repairs.

If you have any questions about your structure, please contact Jared, Dan, or Matt.

Did you know Walker completed more than 1,400 building envelope, forensics, and restoration projects around the nation last year? Here are a few of our favorite recent projects, featuring images captured by our professionals.

 

 

From high-rises to historic buildings, airports to stadiums, we offer solutions for all types of structures. Contact us today to learn how our expertise can save you time and money.

Walker Consultants is proud to work with vital healthcare providers like Nationwide Children’s Hospital, Mount Carmel Health System, OhioHealth Riverside Methodist Hospital, and The Ohio State University.

Over the past 27 years, Walker has completed 36 healthcare projects in Columbus, including 10,183 spaces of parking design and restoration, as well as 17 studies of parking and mobility. Key highlights are below.

Walker’s expertise can save you time and money, and allows your patients to access the care they need as efficiently as possible.

Please give us a call to discuss your needs.

Todd Lohman, PE
Senior Vice President/Managing Director
317.842.6890
tlohman@walkerconsultants.com

Featured Projects

OhioHealth Riverside Memorial Hospital Red Garage

Now featuring a total of 1,633 spaces, the expanded Red Garage has separate ramp systems for visitor and employee areas. Walker’s services included prime design; parking planning; functional design; structural, mechanical, and electrical engineering; access and revenue control system consulting; and signage consulting.

• Learn more about the Red Garage >>

Nationwide Children’s Hospital

Walker designed multiple garages for Nationwide Children’s in a seven-year expansion project, including an award-winning underground garage.

• Underground Garage
• Livingston Ambulatory Center Yellow Garage
• 18th Street Parking Structure

Mount Carmel Health System

Walker has provided parking planning; functional design; and structural, mechanical, and electrical engineering for several structures for Mount Carmel Health System.

• Mount Carmel Grove City >>
• North Garage at Mount Carmel East >>

Charles Hammond‘s article “Grandfathered Dangers: Are Parking Garage Vehicular Barriers Designed to Older Codes Safe?” is featured in the Structural Engineers Association of Texas’ Quarterly Journal this winter. The article, beginning on page 11, discusses the assessment of existing vehicular barriers with an acknowledgement of historical and current code provisions.

Read Charles Hammond’s article on page 11 of the Quarterly Journal.