How do you check hardcore placement claims in Borama?

Hardcore placement competency risks in Borama begin the moment a client accepts a claim instead of a record. A contractor says the base is done, the surface looks level, and the next trade starts. Nothing in that sequence proves the layers went down at the right thickness, that the material met the specification, or that compaction reached the density the design assumed. Without evidence, the floor base is a guess.

What does an unevidenced hardcore claim actually hide?

It hides the three things a floor base depends on: layer thickness, material quality and compaction.

General practice is to place hardcore in layers and to compact each layer before the next goes down. Confirm the layer thickness against the project specification or the design engineer's instruction, because the correct figure depends on the material, the compaction plant and the design. If a contractor skips the layer-by-layer record, you cannot tell whether one thick lift was tipped and rolled once, or whether several thin lifts were each compacted. The difference shows up later as settlement under a slab, cracked floor finishes or a floor that holds water where it should drain.

Material quality is the second gap. Hardcore should be clean, graded crushed stone or approved fill, free of clay lumps, topsoil and organic matter. Loading tickets and batch records show what arrived. Without them, soft or clayey material can be buried under a clean-looking top layer. Ask the approving authority what fill the approval requires, then compare it with the delivery records. Ask the laboratory for the compaction test it would run on that material.

How do you detect the gap before the slab goes down?

You detect it by asking for three records at set points, and by walking the site while each layer is still open.

• Method statement. One page naming the layer thickness, the compaction plant, the number of passes and the moisture target the contractor will work to. Confirm the thickness and moisture against the project specification or the design engineer's instruction.
• Level book. Reduced levels taken on the formation before hardcore, after each compacted layer, and on the finished base. This shows the as-built thickness without argument.
• Compaction evidence. A field density test, or a plate load test on the finished base, carried out by a laboratory the client appoints. Ask the laboratory for its rate and turnaround time before the work starts.

Match each record to the date and location it covers. A single test result for a whole building footprint proves one point, not the base. If the contractor cannot produce a level book, treat the claim as unverified and inspect the open layer yourself before allowing the next one.

How do you close the gap before work starts?

You close it in the contract and in the first site meeting, not on the last day of the base.

Write the evidence you expect into the tender and the contract: layer thickness, the compaction method, who appoints the testing laboratory, who pays for it, and what happens if a test fails. Check what your contract allows before you decide how to handle a failed layer, and take advice before withholding any payment.

Ask for a named supervisor from the contractor's team, with the authority to hold the next layer until the record is signed. Ask for a recent site the contractor completed, and walk it with the person who ran the work. Ask what the layers were, where the test results are, and who witnessed them.

For a diaspora client, appoint someone on the ground to witness the level readings and the sampling, and to photograph each open layer against a marked peg or tape. A witness who is present when the test is taken removes the gap between a claim and a record.

What to do next

Before the next hardcore layer goes down in Borama, stop the pour and ask the contractor for the method statement, the level book and the last compaction test result for that footprint. If any of the three is missing, keep the layer open, take your own levels, and book a laboratory to test the compacted surface. Confirm the required thickness and test method with the design engineer first.