Because parking garages are utilitarian by nature, they are often overlooked when it comes to maintenance. Today we talk about the 2 main things that cause damage to your parking garage and how to fix them. Left unchecked, they can cause serious structural damage to your parking structure over time.

#1: Movement

There are a couple types of movement that commercial parking garages experience.

Dynamic Movement

Have you ever been walking on a parking garage when a car drives by, and you can feel the deck move? With thousands of pounds of weight driving on the deck, it’s inevitable. This is what we mean by dynamic movement.

Thermal Movement

Caused by fluctuations in the temperature. Concrete expands when heated and contracts when cooled.

When a parking garage is built, joints should be installed in order to accommodate inevitable thermal and dynamic movement. If there is a failed expansion joint prohibiting movement, or even worse no expansion joint to allow any movement at all, the concrete becomes stressed. Repeated stress on a solid slab of concrete with the inability to move causes shearing, or cracking, of the slab. These cracks simply mean that the concrete needs to be able to move in this area.

Commercial Parking Garage Damage Due to Movement

The fix?

· Concrete Repair

· Install or replace an expansion joint to allow the deck to move when vehicular traffic passes over it.

#2: Water

Parking structures consist of 2 main components: concrete and steel. Both need to be structurally sound to provide the support the parking garage needs. How else can it stand the test of time with the daily rigorous conditions it’s under? Water causes damage to both.

Concrete is porous by nature, so it absorbs water when it is not properly protected. Here’s why that is a problem.

1. Steel structural components such as rebar are embedded in the concrete slab to provide structural support. When water is absorbed into the concrete, it causes this steel to erode. Rust stains are a great indicator that the concrete in your parking garage is absorbing water and the structural steel components are eroding.

2. In the winter temperatures drop, and concrete is subjected to freeze-thaw cycles. Freeze-thaw is when water has absorbed into the concrete, then the temperature drops below freezing, often during the night. When this happens, any water trapped in the concrete expands. Then as temperatures rise, often during the day, the water thaws causing the concrete to contract back to normal size. Over time this results in cracks and spalling.  

The most common ways we see water damaging parking garages are through:

· Expired caulking and sealants – 

         Urethane caulk, typically used in parking garage construction, has a lifespan of 5-10 years. Once it surpasses its durability limit, its watertight seal deteriorates, potentially allowing water to penetrate and compromise the integrity of the parking structure.

· Ponding – 

          Also referred to as bird baths. Areas of the deck that hold standing water due to low spots in the slab. Standing water absorbs into the slab resulting in freeze-thaw during cold months and deterioration of the embedded steel any time of year.

Long story short, while water is great for humans, it will wreak complete havoc on a commercial parking garage. Over time water results in cracks in the slab, leaks, rotting of the rebar and other steel structural components, and spalling of the slab.

There are a few ways to address these issues, ultimately prohibiting water infiltration:

• Replace the caulking and sealants.

• Overlay the concrete in the low spots. Then slope it towards the drain allowing any water to drain off more effectively.

• Install new drains in any low spots, if an overlay will not accomplish the goal.

Preventive maintenance is always a good idea as well. Here’s what you can do:

• Unclog existing drains or install new drains, if necessary, to prevent ponding on the deck. 

• Install a deck coating. A multi-layer system that creates a waterproof membrane on the deck protecting it from water and wear and tear from vehicular traffic.

• Inspect your garage regularly and look for signs of expired caulk, rust stains, and water staining.  

If you are seeing signs of deterioration or water damage on your parking structure, give us a call or get a quote so we can address any parking garage and concrete repair questions and concerns you have.