Will condensation migrate, in a horizontal way, between the concrete slab and floor tiles?

Asked by Luis Gonzalez Jr.
San Juan, PR

I live in an non-air conditioned apartment and I get condensation in a section of the corridor tile floor, apparently caused by a leaking A/C cold air duct that runs underneath, from the apartment below. In this particular section of the corridor, the floor tiles feel "cold" and one can see a film of condensation. The rest of my apartment floor is warm and dry and condenstation is not formed and the tiles are fine. My question is, if this condensation, that appears in the corridor "cold" spot section, will migrate, horizontally, underneath, between the tiles & concrete slab, to a point in the warm living room floor, with no consensation and cause some tiles in that area, to be detached and get broken? The distance between the corridor "cold" spot, where I get the condensation and the warm dry living floor, where the tiles are detached is about 30 feet. I am claiming damages to the owner of the apartment below, for the detached & broken tiles


David Willson

Answered by David Willson

Sebastopol, CA

Advanced Home Performance

November 27, 2012


The short answer is that it is highly unlikely that water or moisture will migrate 30 feet to another area and cause detached tiles there.

However, if you are seeing a film of moisture on the part of your tile floor over a leaking air conditioner duct, the landlord is facing some serious rot and mold issues inside the floor joists if he doesn't fix the leaky ducts.

Also, if there is another air conditioner duct below your living room tile damage, there could be a smaller leak there that can cause the tiles to release. If not then it is likely poor installation of the tiles by the original installer.

Good Luck!

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