Aus Water underfloor heating and epoxy grouts

[istefanov87]

Hello,

I did some reading here and there, but the opinions seem to diverge at some point and I am not able to translate the info to my particular question. I have a water underfloor heating (thermal pump and so on) installed and am currently having the bathrooms (and not only) done. I am wondering about getting the epoxy grout (PCI Durapox premium), as there seem to be 3 opinions that sound equally reasonable to someone like me (zero prior knowledge):

• some say to avoid epoxy grout in this case as it is very hard and the thermal expansion may break the tile due to no room left for it
• some say that the above is possible, but fixable by leaving a non-epoxy joint every X meters or something
• and finally, some say that the thermal expansion should not be significant enough to cause breaking of the tile due to the not too high temperatures it reaches

Can anyone share actual experience and/or some theoretical base so that I can educate myself on that ? They seem to have 3 of the 4 colors I need on the epoxy, so I can do most of the space with it, as long as I do not risk having cracks in the tiles in a few years because of this. The guy that is installing the tiles is really good in what he does and I am 99% sure that the installation itself will be good, just wondering if there is more to it than just installation (like physics laws or something that we cannot fight).

 

[Tile Marble Granite]

Hello,

I did some reading here and there, but the opinions seem to diverge at some point and I am not able to translate the info to my particular question. I have a water underfloor heating (thermal pump and so on) installed and am currently having the bathrooms (and not only) done. I am wondering about getting the epoxy grout (PCI Durapox premium), as there seem to be 3 opinions that sound equally reasonable to someone like me (zero prior knowledge):

• some say to avoid epoxy grout in this case as it is very hard and the thermal expansion may break the tile due to no room left for it
• some say that the above is possible, but fixable by leaving a non-epoxy joint every X meters or something
• and finally, some say that the thermal expansion should not be significant enough to cause breaking of the tile due to the not too high temperatures it reaches

Can anyone share actual experience and/or some theoretical base so that I can educate myself on that ? They seem to have 3 of the 4 colors I need on the epoxy, so I can do most of the space with it, as long as I do not risk having cracks in the tiles in a few years because of this. The guy that is installing the tiles is really good in what he does and I am 99% sure that the installation itself will be good, just wondering if there is more to it than just installation (like physics laws or something that we cannot fight).

Why use epoxy grout? loads of Pros and Cons about using epoxy
Use powder grout and have no worries about cracks in the tile etc.
Cementitious grouts have been used for centuries without issues
All it needs is periodically maintenance, once a year

 

[Dan]

You say 3 of the 4 colours, are you doing different coloured grouts in the same room?

As above, I think I'd go with cement based with an additive which is the most flexible version of it.

Just refering to the last point of the 3, I also wouldn't have thought the thermal expansion would be too great for epoxy / tiles. A cold snap and the window being left open would cause it to cool below what it wants to sit at, and that's more of a problem than operating it normally from say 10 to 25 degrees Celsius.

Generally the floor wouldn't expand or retract too much in that 15 degree range. So leaving the stat on so the floor never cools in the colder months of the year would be more helpful than changing grout to epoxy then worrying about it (not that I think I would worry - I can't think of a floor ive done with electric ufh [so not always as hot as wet ufh] that ever had a tile crack when using epoxy, not that it would be the first choice as the labour time increases quite a bit so 2 part cement based usually was the one).