Concrete floor moisture test

How to test a concrete floor for any moisture problems lurking there.

If you're installing flooring over concrete, first check for moisture. To test a concrete floor (whether new or existing concrete) for any moisture problems, make sure your floor is totally dry first. Cut a 3-foot square of plastic sheeting; place it in the center of the room; and seal all the edges down with duct tape. Then leave it alone for at least 24 hours (two or three days is even better). Then peel the plastic back and inspect for moisture. If you see water droplets on the underside, or a darkened concrete square, it indicates potential excess- moisture problems. If this is the case, ask the flooring supplier for advice before proceeding. If you're installing a floating wood floor in a kitchen bath, entry hall or anywhere, surface water may be a factor. Be sure to discuss this moisture problem, as well. And that's the On The House Tip for today.

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