Expert: Stephen Hayes - 10/25/2007

Question
We installed porcelain tile over in-floor heating (with jipcrete over the heating tubes) and it came up after a few days.  Is there a special method or materials we were missing?

Answer
There are several things you left out in your question so we can't give you anything definite to solve your problem.  Was the adhesive the product that the tile manufacturer recommends for use under these tiles.  Did you put enough adhesive down with the correct trowel size.  Was the heating system turned on during your application of adhesive to the point where it may have caused the adhesive to dry too quickly so it could not set up properly.  Did you use a correct roller. Was the HVAC system in the home at the proper temperature range and hunidity levels for the application of the adhesive. Did you do a moisture test on the jipcrete that would let you know if that subfloor could accept the adhesive without compromising the tackifiers in the adhesive.  There are several other things that should be checked before installing the tiles.  We would suggest that you contact the tile manufacturer to see what adhesive they say is proper, for these tiles, and that manufacturer's installation specifications should dictate trowel size, any acclimation time needed, etc.  The adhesive manufacturer should be contacted to make sure you applied the adhesive properly, allowed a proper set up time, and if that adhesive can be used on jipcrete.  You can get further information by visiting the website of TCA, which is the Tile Council of America, where you may find information about your tile being able to be installed over the heating system you have.  If you have any further questions, please feel free to contact us at;
MBD Floor Covering Inspection Service
P. O. Box 291
Mountain Lakes, NJ 07046
973-334-9747
<steve@mbdinspectfloors.com>
<mbdinspectfloors.com>

Cordially,

Stephen Hayes