[Bobster]

Hello all,

Thanks for taking the time to look at my question. I got a little too heavy-handed with chisel and/or hammer when removing a cracked tile out of my shower and damaged the (concrete) backer board. For scale, the tiles are 6")

Can this be repaired? I was thinking I could either go with some something along the lines of an epoxy and inject it in there to firm things up, or could I just lay on the thinset or mastic or ??? kinda heavy and let it be? This is the wettest corner of the shower if that matters.


Thanks for your time,

Bob

[Termite]

No, I would not consider trying to repair that. Nothing you do will restore its integrity all that well. Thinset would be a band-aid fix though. Fact is, there are two other major issues with your shower than will contribute to its eventual demise.

First, the installer used mastic. Mastic should never be used in wet areas...Thinset is what's needed.

Second, the backerboard doesn't have a waterproofing agent applied to it. That's ok if you have a vapor barrier between the wonderboard and the studs, which you might. Grout and backerboard are incredibly permeable, and water that infiltrates the grout must be confined to the backerboard (to protect the studs from rot and the wall from mold) or prevented from getting in it in the first place.

[Bobster]

thkctermite,

Thanks for the info, I'll look for a vapor barrier. Now I get to choose between bandaid with thinset or do-over. Fun!

Does sealing grout in general help minimize water penetration? I'm wondering if I can buy some time by sealing the grout, or perhaps even using epoxy based grout.

Thanks again,

Bob