Thread: Disintegating concrete under tile

The house was built in 1959 and the basement tile could be any year between the 60's and 80's. One half of the basement is a garage and the concrete is in great condition. Only on the side of the basement with tile do I see what appears to be disintegration of the concrete slab under the tile. The concrete seems to have turned to dust maybe an inch or more deep in some area, and it is bad at the seams between the tiles, and where the four corners of tiles meet it is really bad.
One theory I have is that moisture is trying to migrate up from below the slab, it cannot flow trough the tiles so all the moisture is forced between the spaces between the tiles. More airflow would be passing where the 4 tile meet.
On some of the concrete block foundation walls I have minerals coming through, efflorescence. Maybe this is related.
There had been a history of some basement flooding and when I moved in in 2002 there was some carpeting on the floor. I don't know if the carpeting trapped moisture.

A second theory would be that a previous owner used some kind of chemical to clean the tile floor and it soaked down between the tiles and has dissolved the concrete.

A third theory would be that the side of the basement with the tile was a second pour of concrete, and was never right from the beginning.

I'd like to hear if they had ideas on:


1. What the problem as far as the disintegration of the concrete flooring

2. Any suggestions on how to repair it for sale.

3. What type of tile they think this could be.

Thanks
Cj

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radiant heat in the floor?

can not tell size of tile from photo...
but
if 9 x 9
possible asbestos tile

Originally Posted by Joseph P. Hagarty

radiant heat in the floor?

No radiant heat, especially for a house in Georgia.

Cj

The tiles looks like 9x9 tiles and if so you have a 98% chance that they will have asbestos.

You are going to need to look at the concrete so all of the tiles will need to be removed.... Once you have all of the tiles removed and you can see the clean concrete you will then be able to tell better what you are dealing with.

I have never seen concrete turn to powder like you are showing in the pictures. If the owner used a chemical strong enough to do that to the concrete then the tiles would not be a problem!

As for the repair, you need to get all of the tiles up to start. Go to the EPA site and they will tell you about asbestos and what you can do as a homeowner.

It does sound like you have moisture problems for starters....

I would start by hiring an experienced home inspector in your area and let them come and take a look. Take their advice and then move ahead.

Anyone else have any idea on what would cause the concrete to turn to powder?

Thanks
Cj