Construction Materials Testing
Construction materials testing is an independent 3rd party testing and inspection of the construction materials and procedures that make up your building. Obviously you want to ensure that the key individual components of your building are constructed in accordance with the standards that the engineers and architects have established for that part of the building. This helps ensure the overall building is built well, will last for decades, and is safe.
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What is Tested
​CMT companies can test a variety if materials and procedures, but below are some of the more common ones.
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Soil moisture content and density
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Soil lime stabilization
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Pier drilling for foundations
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Post-tension cable for slabs and beams
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Concrete mix design
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Concrete break tests
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Mortar and grout testing for masonry
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Structural steel welds
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Structural steel bolt tension
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Fire proofing coverage and thickness
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Waterproofing coverage and thickness
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Building envelope watertightness review and inspections
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Not only is this testing information important to you, your engineers, and GC, but most city inspectors will rely on these tests to make sure the building is being constructed properly. And the city inspectors won't give your GC a green tag until they review the test results.
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Pricing out CMT Services
The cost of CMT is not insignificant, so it is a cost you want to estimate with some accuracy in your early draft development budget. I usually budget $1.20/SF for an early budget number. You can refine that number by sending your schematic design package of the project to a CMT firm and ask them to estimate a testing budget for the project. Add 10% to this estimate for good measure and plug it into your development budget. After you get to the CD level of your plans and specs, send them to at least a couple of CMT firms to get competitive pricing. The materials testing requirements are usually listed in the design package specs, and the geotech report for soil testing.
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CMT firms will not contract for a fixed price. They will charge you per trip charge, inspection done, and lab test conducted. The amount of trips, inspecting and test needed for a project depends upon how many tests the GC superintendent calls in.
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Watch the CMT Charges to Make Sure You Stay Withing Budget
The GC team, and specifically the superintendent, should be aware of all the various testing requirements that are listed in the project specifications. In my experience, I almost always go over budget on CMT costs. CMT firms probably give me too low an initial estimate of cost so that they win the contract. And sometimes the GC superintendent will call in too many inspections, or delegate to his subcontractors to call in inspections. If this happens, subs will call in inspections willy-nilly at their convince. They can also call in tests for materials that are not ready to be tested, in which case the owner still has to pay for the trip charge. And the CMT firm could test something that fails, and the owner has to pay for the re-test.
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What if your GC Fails a Test
To effectively manage a development, you don't need to know all the science and engineering behind the testing or the materials that need to be tested. That is the job of the engineers and architect. However, as the representative of the owner of the building, you do have to know that if the GC fails a test, he will take the corrective action to fix what failed, and make sure he passes the next test. You can't allow your building to be constructed with materials that don't pass minimal standards that the engineers and architects have set for the building.
The CMT company will email the GC and you the test results after each test or inspection. This will be dozens of reports on a typical project. As a development manager, I don't even read most of those reports, and to be honest, if I tried to read them, I wouldn't be competent enough in the engineering to decipher what the report says. Again, all I need to know is that all tests passed. And if a test failed, I need to make sure the GC is taking corrective action.
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Make sure that you tell your CMT firm that if a test or inspection fails, be sure to highlight that to you somehow, so that you can follow up with the GC on the corrective action. When you are getting dozens of test reports emailed to you, most of which you won't even read, you don't want to lose sight of a report that shows a failure.
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