How necesary is it to use something like Ditra on a 30 year old basement floor?
artisanfarms
| Posted in General Questions on
I’m planning an ~550sqft tile floor in the family room of my Pretty Good House remodel project. The basement floor was poured sometime between 1980 and 2000, has one small crack and stays dry year round. How necessary is it to install some type of uncoupling layer between the tile and existing floor? The basement walls are insulated on the inside but I don’t know what, if anything, is underneath the slab.
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Replies
The Tile Council of America handbook allows installation directly over concrete as long as there are no cracks or moisture issues. "One small crack" may or may not be ok--how long has it been there? Has its size changed at all?
It's good that you don't see visible moisture, but have you tested to see if there is moisture in the slab that is evaporating into the air before you can see it? Taping a piece of poly sheeting to the floor and leaving it for days, weeks or months, depending how careful you want to be, is the typical method for checking for moisture.