Waterline tile install and future cracking

[Coz]

I am pondering installing waterline tile to conceal large mortar joints on my coping. The coping hasn't been installed yet, but the fiberglass shell is "off level" enough that one corner will have an inch of mortar. The tile will cover this up the mortar joint and make the whole shell appear to be level.

I am concerned about the joint between the mortar and fiberglass shell. I know there will be some microscopic movement and I'm worried about it causing future cracking in the tiles. Is my concern valid or does the silicone allow enough movement to prevent cracking?

Thanks
Jim

 

[duraleigh]

They will use mastic and grout made for that application,

Cementitious grout (Is that a word??) is too brittle (like you said) and will crack. Not completely sure but I think a 2-part epoxy will do the job. You are not attempting this DIY, are you? Count on your tile company to get it right.

 

[ajw22]

Look at silicone tile grout...

NovaFlex Silicone Tile Grout

NovaFlex Silicone Tile Grout is a non-corrosive, non-flowable paste that cures to a rubber-like solid when exposed to atmospheric moisture.

novagard.com

Home - Flextile.com

Providing the tile, flexible silicone grout and adhesive, and guidance that you need to turn your RV into a true home away from home!

flextile.com

Waterline Tile Installation - Further Reading

www.troublefreepool.com

 

[Coz]

They will use mastic and grout made for that application,

Cementitious grout (Is that a word??) is too brittle (like you said) and will crack. Not completely sure but I think a 2-part epoxy will do the job. You are not attempting this DIY, are you? Count on your tile company to get it right.

Ok, got it, you are saying the mastic/epoxy will allow some flex, along with flexible grout/silicone, and cracks won't form. Good! Yes, I have a recommendation on a professional installer.