moisture on tile floor in summer - Contractor Talk - Professional Construction and Remodeling Forum

72chevy4x4 · 07-06-2009, 07:29 PM

HO asks for a solution to problem-during the summer months, the tile floor in the kitchen/dining rm and foyer gets condensation on it (from front of foyer to kitchen approx 28' away) during the summer with AC running full time (no set back).

the tile is likely directly adhered to the concrete slab. there IS high water issues on the lot and drainage has been an issue in the back yard of the house.

My thougts are that the slab is drawing moisture up into the space and that's the cause of condensation on the tile during AC use. Is this correct/possible?

**Leo G** · 07-06-2009, 07:46 PM

Sounds like your high water table may be the problem. Use a silicon water sealer on the tile and grout. Very temporary though. Fix the high water with drainage around the house and there is a good chance it will go away.

Insuranceclaims · 08-31-2009, 05:11 PM

Have you solved this problem yet?

Due to the water surrounding the slab, it sounds like excessive vapor emission rising through the slab.

While the specs vary now, the average amount of vapor pressure that should exist before causing significant damage is 3-3.5 lbs. of vapor pressure per 1000 sf per 24 hours.

I call water a "funny animal". Water travels the path of least resistance. In this case, there is mostly likely an excessive amount of vapor pressure, 5 lbs., trying to escape the surface. First, the vapor will egress through the grout lines. In the mean time, the excessive pressure is weakening the integrity of the thin set and tile. The tile will eventually become hollow and or buckle or crack.

There are methods to check and solve. Yet, first the water outside needs to be redirected.

Let me know if you need more info.

72chevy4x4 · 09-01-2009, 08:06 PM

I would be interested in more info. I'm still waiting on the HO to make decisions about the remodeling job...nothing else was done about the condensation on the tile. wonder if it could be impacted by an improperly sized AC unit?

neolitic · 09-01-2009, 11:09 PM

Sounds to me like no vapor barrier,
or at least a compromised one.

Insuranceclaims · 09-02-2009, 01:39 AM

What city is the job in? I am in Florida, but maybe I can locate someone in the area who can help. It is possible to get preliminary readings of moisture content under the tile with the use of a Tramex MoistureConcrete Moisture Encounter 4. Other tests can determine temperature and humidity of the concrete under ASTM-2170 and calcium chloride test.

Yet, for these tests, there needs to be several areas of clean slab.

Anyway, again, what city is the job in? I will check tomorrow.

10fingers · 09-02-2009, 06:24 PM

Some research:

http://www.thefloorpro.com/community...ting-tile.html

http://www.proconweb.com/pdfs/public...11_30_2007.pdf

I like the dew point angle. Cold air + warm = moisture. Any problems with the windows. See any moisture around them? What about the mill work around the windows? Signs of staining?