I received a lot of good information in my post but think I did not make myself completely clear.
I had moisture damage in my home and had it inspected by a leak detection company.
They found moisture damage in the obviously moisture damaged area and promptly announced I had a wet slab problem.
They then went into the master bathroom and closet,not the shower, and checked moisture in the stone tile in those areas along with the ceramic tile floor in the guest bath room which has a tub. they showed me readings on there moisture meter that showed reading of between 95 and 98%.
I subsequently found that a leaking garbage disposal had been leaking out of the back of the kitchen sink for most likely a year caused the flooring damage.
Was the tile inspection using a moisture moisture meter a valid method as I need to go to arbitration on this?
So what you are looking for is an expert witness and you are asking on a public forum with pending arbitration? You should hire someone like Chuck Evans, Charlie Bottger, or David Anderson to work with you. I don’t know where you are located but there should be a highly experienced inspector in your area.
No. It’s not a valid inspection method and in my opinion, you cannot draw definitive conclusions from it. Do you know specifically what make/model moisture meter was being used, how it was calibrated, how many readings they took across the entire slab and how the readings compared to each other by location/proximity?
If you have a “wet” slab there is a source of moisture. If it’s from above, like a plumbing leak, it’s going to be localized, along with any related visible damage. If it’s moisture migration through the slab, due to lack of a moisture barrier, it’s going to be widespread and any apparent damage is likely to be also. There are test methods for moisture migration through a slab, but they don’t involve the use of capacitance moisture meters applied to the surface of the finished floor.
Some ceramic tiles contain heavy metals, which will trigger a high reading in a pinless moisture meter. If you suspect this, try scanning an area you know is dry to be sure.