Trade walkthroughs
How to inspect foundations
The foundation carries everything above it, and once it's poured and backfilled you can't see it again. So the inspection front-loads onto what's under and inside the concrete: the bearing soil, the formwork, the reinforcement and cover, and the embeds — all verified at the pre-pour hold point. Then you confirm waterproofing and drainage before the backfill hides them.
For the superintendent and QC manager running foundation pre-pour inspections on footings, walls, and slabs alongside the geotechnical and special inspectors.
Step by step
Confirm the bearing and subgrade
Verify the excavation reaches the specified bearing stratum and elevation, that the subgrade is undisturbed or compacted as required, and that the geotechnical engineer has approved the bearing where their sign-off is required. Founding on the wrong soil is a settlement problem you can't inspect away later.
Check formwork, dimensions, and layout
Confirm footing and wall dimensions, location, and elevation against the drawings, and that formwork is braced and clean. Verify keyways and steps are where the details show them.
Verify reinforcement, dowels, and cover
Check bar size, spacing, laps, and hooks, that dowels for walls and columns are placed and will splice correctly, and that cover is maintained against the earth and forms. Bars sitting on the mud instead of on chairs have no cover and no value.
Confirm embeds, anchor bolts, and sleeves
Verify anchor bolts, hold-down anchors, embed plates, and any sleeves or under-slab penetrations are located and secured per the drawings before the pour. Column anchor bolts are the ones steel erection will not forgive.
Release the pre-pour hold point
Confirm the special inspector has verified the reinforcement and the pre-pour inspection is signed off before concrete is ordered. This is the hold point — the foundation pour doesn't begin until it clears.
Observe placement and check the concrete
Watch placement for segregation and consolidation, confirm the mix matches the spec and the testing lab takes samples, and verify cold-joint locations and waterstops at construction joints where the drawings call for them.
Inspect waterproofing, drainage, and dampproofing
Before backfill, verify below-grade waterproofing or dampproofing coverage and continuity, that protection board is on, and that foundation drains, filter fabric, and drainage stone are installed per the detail. This is the last look before it's buried.
Verify backfill and document
Confirm backfill material and compaction, that walls are braced or floors are in before backfilling against tall walls, and photograph reinforcement, embeds, and waterproofing before they're covered. Log any out-of-tolerance element for the engineer.
What gets missed
- Pouring before the geotechnical or special inspector has verified bearing and reinforcement.
- Reinforcement laid on the subgrade with no chairs, leaving the steel with no cover against the earth.
- Backfilling against a foundation wall before it's braced or the floor is in, and cracking the wall.
- Skipping the below-grade waterproofing and drainage check — the defect you only find when the basement leaks.
- Mislocated column anchor bolts discovered when the steel crew tries to set the first column.
Questions people ask
- What's the single most important foundation inspection?
- The pre-pour hold point. Bearing, reinforcement, cover, and embeds are all permanent once concrete is placed, so that inspection is verified and signed off before a truck is ordered.
- Why inspect waterproofing and drainage before backfill?
- Because backfill buries them. A holiday in the waterproofing or a crushed drain becomes invisible the moment the trench is filled, and the only symptom later is a wet basement. Verify and photograph coverage first.
Standards behind it
Terms worth knowing
Checklists that make this a one-tap job
Free, field-ready checklists, each with the photo every item needs before it can be submitted.
Related guides
- How to inspect a concrete pourRun the pre-pour inspection, watch the pour, and check the finish — formwork, rebar, embeds, mix, and curing — because concrete only gets inspected once.
- How to inspect sitework and earthworkInspect sitework and earthwork in sequence — erosion control, excavation, subgrade, fill and compaction, utilities, and grading — before each layer is buried.
- How to inspect the building envelopeInspect the envelope as a system — air barrier, water-resistive barrier, flashing, transitions, and sealants — with the continuity and mock-up that make it perform.
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.