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How to inspect a parking structure

A parking structure is a concrete building whose roof and floors are the same surface cars drive on, exposed to water, salt, and constant load. Everything that protects the structure — the concrete cover, the traffic coating, the joint sealants, and the drainage — is what stands between it and a corroding, spalling deck. The post-tensioning that lets those decks span is life-safety scope, verified at hold points with the special inspector. Inspect the deck as the durability system it has to be.

For the superintendent and QC manager verifying cast-in-place and post-tensioned parking decks against the structural drawings and durability details, alongside the special inspector.

Step by step

  1. Verify formwork, reinforcement, and cover at the pre-pour

    At the pre-pour hold point, confirm formwork, bar size and spacing, and especially concrete cover, since cover over the steel is the first line of corrosion protection on an exposed deck. Verify with the special inspector before placement — it's permanent once the deck is poured.

  2. Inspect post-tensioning tendons and stressing

    Where the deck is post-tensioned, confirm tendon layout, profile, and anchorage against the drawings before the pour, and observe that stressing is performed and the elongations recorded and accepted by the engineer. Frame this as observed and documented at the hold point; the special inspector and engineer certify the post-tensioning — it's high-energy, life-safety work.

  3. Confirm the concrete mix, placement, and cure for durability

    Verify the deck mix matches the durability spec, watch placement and consolidation, and confirm the finish and cure — a proper cure and the right finish are what give the surface its wear and de-icing resistance. A deck that dries too fast or is over-finished sets up early scaling.

  4. Check slope, drainage, and the absence of ponding

    Confirm the deck is sloped to the drains per the plan and that after the pour water actually runs to the drains without ponding, since standing water and salt are what drive deterioration. Verify drains, trench drains, and their piping are set and clear.

  5. Verify the traffic coating and surface preparation

    Confirm the traffic-bearing waterproof coating is the specified system, that the concrete is cured, clean, and dry enough to receive it, and that each coat and the aggregate broadcast go on at the right rate. The traffic coating is the deck's waterproofing over occupied space — a thin or poorly bonded coat fails and leaks onto the level below.

  6. Inspect expansion joints and sealed joints

    Verify expansion-joint systems and all sealed joints — construction joints, control joints, and the coating terminations — are the specified systems, free to move, and continuous, since the joints are the planned openings in a deck that has to shed water. Confirm the coating ties into the joints and drains correctly.

  7. Check barriers, connections, and life-safety elements

    Confirm vehicle barriers, guardrails, and their embedments and connections meet the design, and verify stair, ramp, and any exposed structural connections. Frame guardrail and barrier capacity as verified against the approved details; the engineer governs the design load.

  8. Document the concealed and durability work

    Photograph reinforcement, cover, tendons, and joint details before they're covered, keep the pre-pour, stressing, and coating records in the file, and log wrong cover, thin coating, ponding, or fouled joints as nonconformance items — they're what determine how long the structure lasts.

What gets missed

  • Insufficient cover over the reinforcement on an exposed deck, the fast track to corrosion and spalling.
  • Traffic coating applied thin, over a damp deck, or at the wrong rate, so it fails and leaks below.
  • Ponding water because the deck wasn't sloped to drain, concentrating salt and deterioration.
  • Expansion and sealed joints fouled or discontinuous, letting water into the structure.
  • Treating the field walk as certification of the post-tensioning — the special inspector and engineer certify it.

Questions people ask

Why is a parking structure inspected so much for durability?
Because it's a concrete structure left exposed to water, freeze-thaw, and de-icing salt while carrying traffic, and those are exactly the conditions that corrode reinforcement and spall concrete. Cover, traffic coating, drainage, and joint sealants are the durability system, so they get the attention that finishes get in an enclosed building.
Who certifies the post-tensioning?
The special inspector observes tendon placement and stressing and the engineer of record reviews the elongation records and accepts the work; where the code requires it the AHJ is involved. Post-tensioning is high-energy, life-safety work — your role is to observe, coordinate the hold point, and document, not to certify it.

Reading the steps is one thing. Proving you walked them is the job.

RTI holds the submit button until every mandatory item is answered and the photos are attached, then chains the record so it can be proven untouched later.