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Why is it Raining Inside my Parking Structure?

Raining Inside Parking Structure
Figure 1: Raining Inside Parking Structure

Ever wonder why it is raining inside your parking structure?  Well, it is a sign that your parking structure needs attention. Water is the number 1 cause of parking structure deterioration. Water-saturated concrete can freeze, expand, and spall. Combined with oxygen, water can also cause corrosion of the concrete reinforcing. Exposure to deicing salts accelerates this process. As reinforcing steel expands as it rusts, this process also leads to concrete spalling. Spalled concrete provides less cover or protection of the structure which leads to further (and accelerated) deterioration if not repaired in a timely manner.

Water is the number one cause of parking structure deterioration.
Figure 2: Cause of Damage

The top level of your parking structure not only provides possibly the least desirable parking spaces, it serves as the roof of the facility. Controlling water in the form of rain or melting snow at this level is the least expensive way to extend the life of your parking structure and minimize maintenance costs. Controlling the water runoff involves shedding water to drains as quickly as possible.

Ponding water is unacceptable as it saturates the concrete and leaks to lower levels. The installation of supplemental drains can easily and permanently address ponding. Urethane joint sealant at the top level is exposed to UV Sunlight and tends to break down within a few years. The breakdown of this product leads to cracks in the sealant allowing leaks to the levels below. This leads to degradation at the lower levels like that described above at the top level.

Water is ponding on the top floor of this parking structure.
Figure 3: Ponding

Therefore, it is important to visually inspect joint sealants annually and budget joint sealant replacement approximately every three years at the top level. Urethane joint sealant replacement will cost approximately $4.50 per linear foot but provides one of the best Return On Investment (ROI) when it comes to parking structure maintenance.

Given the accelerated rate of parking structure deterioration, this is cheap insurance against having to perform more expensive repairs in the future.

A crack has formed in the concrete joint sealant.
Figure 4: Cracked Sealant

The IEI Structural Engineering Advantage

The engineers at IEI specialize in parking structure restoration. They will be glad to walk your facility and let you know of any conditions that require immediate attention and what maintenance activities you can perform now to extend the life of your facility. Give them a call today.

  • Trusted Resource: IEI’s expertise is trusted by owners and property managers of all sizes, including some of the nation’s largest property portfolios. In addition to answering the request for advice, consulting, and peer reviews, IEI is sought after for their expertise in the form of educational speaking events for national organizations as well as articles in major national publications.
  • The Right Level of Expertise: The IEI professionals performing your work are graduate and professional registered engineers. They possess the necessary engineering fundamentals required to understand the many elements that affect the performance of your faculty.
  • Industrial Rope Access: The IEI engineers have extensive training in SPRAT Certified Industrial Rope Access. Not only are dedicated tested and certified roof anchors not required for this method, but it allows for efficient access to 100% of a building’s facade compared to a Rope Descent System (RDS) or Swing Stage which accommodate very limited access.
  • Thoroughness: IEI is commonly complimented, by its existing customers, for being thorough. IEI’s state-of-the-art techniques provide a more thorough Condition Assessment. The time to know the true extent of any deficiencies is now, not after the restoration contractor has started work which leads to change orders and damaged reputations.
  • Real Time Cost Estimates: IEI’s relationship with some of the nation’s top restoration contractors allows for accurate real time costs estimates. The time for accurate cost estimates is now, not after the work is budgeted and the bids come in that are too high. IEI estimates are typically within 5 to 10% of actual qualified bids.

Innovative Engineering has more than 20 years experience in parking garage restoration.


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    About the author

    Principal Structural Engineer with Innovative Engineering Inc. has over 37 years experience helping owners reduce parking structure maintenance costs. He can be reached at 770-517-5507

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