Please help me and advise a solution for an open corner between two tile walls. The tile shower/bathtub was installed 30 years ago. It’s held up very well except one corner, the gap after cleaning it out is 1/4 – 3/8th. I think it was installed that way very poorly then filled with a heavy filler – maybe a grout or plaster. I had caulked over it years ago and its lasted until now. I need to redo that corner. I’ve chiseled out the grout and I need to fill this corner before caulk. The cavity between the two nailers is somewhat deep to complicate matters. I was thinking of hydrolic cement but just guessing. Any comments are appreciated.
SA
Replies
Any sort of grout-like material should be fine. You simply want something to form the backer for the caulk which will be the finish and seal. Aim for a caulk layer that's around 1/4" thick -- thicker is NOT better when it comes to caulk.
And clean the joint carefully before caulking. I've found wiping with acetone after whatever other cleaning you do seems to help with adhesion, in spite of small amounts of old caulk that may remain.
I went with rock hard water putty and a large bead of 100%Silicone shower caulk. Can I put another coat of silicone on top of the first coat of silicone if I see places that sunk in ?
Thanks
Generally, silicone will NOT stick to silicone. I have had modest success by first wiping the first layer of silicone with acetone, but I wouldn't want to bet on it.
Should have used backer rod to fill the overdeep recess of the joint, then caulk to fill it flush.
Backing
I didn't know about backer rod however considered expandable foam to fill the void between the nailers. Then on second thought worrying about slight movement with the foam - I just went ahead and overfilled the opening until it filled forward - 1/4 shy to allow for the silicone. I think I have thoroughly filled the corner -
Thanks for the suggestions from all here !
SA
The thing is, you WANT the silicone to be able to flex. The puprose of anything behind it is to merely control the depth so it doesn't get too thick (since thicker is stiffer and more likely to separate).
uhhhh....what?
You're worried about slight movement with the foam, but went ahead and put rock hard water putty in the joint?? I don't get that logic.
Anyhow....
Your wall planes are obviously experiencing dissimilar movement. First of all you should be concerned about waterproofing membrane behind the tile, then deal with sealing movement with a flexible joint. Unfortunately you're probably SOL in dealing with a membrane at this point, but the last thing you want to do is fill the joint with a rigid materail like water putty or grout in this case--or in any case!
You want to use a quality flexible sealant and use (as earlier poster mentioned) backrod if necessary. This is the case for every change in wall plane where tile meets tile or disimilar materails abut one another. Caulk should be installed in an "hour glass" type profile, if possible. It's a proportional apsect to caulk installation; not an absolute volume determination. Dan doesn't know what he's talking about when he advises "Less is more" mantra with regard to caulk.