Concrete and floor moisture testing in Southern California
Moisture is behind most floor failures. We test concrete slabs (ASTM F2170 relative humidity, ASTM F1869 calcium chloride and pH) and wood subfloors before installation, and test failed floors to show where the moisture is coming from.
Before new flooring goes in
- In-situ relative humidity testing of the slab (ASTM F2170)
- Calcium chloride moisture emission testing (ASTM F1869) when the manufacturer lists it
- Surface pH testing for adhesives and resilient floors
- Moisture content of plywood or OSB subfloors and of the flooring itself
- Room temperature and humidity, and whether the building is at living conditions
- A written report comparing every reading to the manufacturer's limits
After a floor fails
Cupping, buckling, swelling, mold, adhesive failure and lifting tiles often trace back to moisture. We map readings across the floor, check the slab or subfloor, look for leaks, crawlspace or vapor-barrier problems, and explain whether the moisture came from the building, the installation or an outside event.
Who orders moisture tests
- Homeowners before a remodel
- Flooring retailers and installers who want the job documented
- Builders, general contractors and HOAs on new construction
- Insurance adjusters and attorneys after a water loss or claim
Moisture testing questions
Do I need a moisture test before installing flooring on concrete?
Usually yes. Almost every wood, laminate, vinyl and adhesive manufacturer sets a moisture limit for concrete and requires a test before installation. Skipping it is one of the most common reasons warranty claims are denied.
What is ASTM F2170?
ASTM F2170 is the in-situ relative humidity test. Small holes are drilled into the slab, sensors are left to equalize, and the reading shows the moisture inside the concrete. Most manufacturers now accept or require it.
What is ASTM F1869?
ASTM F1869 is the calcium chloride test. It measures how much moisture the slab surface gives off over about 60 to 72 hours. Some manufacturers still list limits for it.
How long does a new concrete slab take to dry?
There is no safe rule of thumb. Drying depends on slab thickness, mix, curing, vapor barrier, weather and HVAC. The only way to know is to test the slab against the flooring manufacturer's limits.
Can you test moisture in a wood subfloor?
Yes. We measure the moisture content of the plywood or OSB subfloor and of the flooring itself, check crawlspace conditions where there is one, and compare the difference to the manufacturer's installation limits.
Why does concrete pH matter?
High surface alkalinity can break down adhesives and some underlayments. Many adhesive and resilient flooring manufacturers list a pH range that must be met before installation.
Book a moisture test
Tell us what you're seeing and we'll explain the next step. We cover every county in Southern California and only inspect. We don't sell or install flooring.