Tiled shower with molded plastic shower base.
At the bottom course of tile where it overlaps the nailing flange of the base, I was taught that you should not caulk the gap because any water that gets behind tiles (through a flaw in grout, for instance) would then have no way to escape.
True or not?
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Replies
I would check the manufacturer's installation specifications for the shower base. I just checked one for American Standard and it said to caulk, fwiw.
You plan on having a flaw in your caulk job?
"You plan on having a flaw in your caulk job?"Not caulk, grout. It's easy for tile setters to leave small voids in grout. For that matter, even good grout joints are not completely waterproof.I don't know how good that long-ago tile setter was who did the shower (sometime in the late 60's).BruceT
Edited 4/8/2008 8:46 pm by brucet9
I refuse to use caulk in a shower in any capacity.
I don't like mush either.[email protected]
even in the tiled corners ...
where it's best to caulk?
soap dishes ... shelves ...
any joint between dissimilar materials ...
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
Nope. I use a Mapei modified grout and have yet to have a corner joint fail (I usually make my own shelves/niches out of similar materials to the rest of the shower). John Bridge grouts all his corners, too.In any case, I'd rather mix up a little grout in the future to fix a crack than dig out disgusting, moldy caulk.edit: I have only tiled showers that are all tile (including floor) or have a cast iron tub...if I was dealing with an acrylic base or acrylic tub, I might think differently.Edited 4/8/2008 10:24 am ET by jesse
Edited 4/8/2008 10:26 am ET by jesse
Hi Bruce.
Years ago I learned that you caulk the shower base but leave the weep holes open which are just behind the apron at the lowest point.
Thats what I do. FWIW
"...but leave the weep holes open which are just behind the apron at the lowest point."Are you talking about the shower base or about sliding door bottom track?
BruceT
The fiberglass pan.
The low spot just behind the apron is a weep drain, isnt it?
I don't know what that is for, but my old base doesn't have any such groove at the threshhold.
BruceT
The Aker/MAAX website says caulk the underlayment to the fixture with waterproof caulk but nothing about the tile.
In the installation dwgs you can see the kerf in the pan just behind the apron/threshold.
I guess it is captains choice.
If you use cement backer board and tile, both will last long time so perhaps it is not big deal either way!?!?
Most would caulk with a sanded caulk.Regards, Scooter"I may be drunk, but you're crazy, and I'll be sober tomorrow." WC Fields, "Its a Gift" 1934
The joint between wall tile and any type of shower base has always been problematic. Latex caulk, color-matched, sanded, or otherwise usually disintegrates over time due to moisture. It just won't hold up so most manufacturers recommend caulking with pure silicone. Messy, doesn't adhere easily, and prone to mildew. Grout the joint and it will usually crack if the base is fiberglass.Lately I've been using Schluter Dilex profiles to bridge this joint and love the results. My goal is a caulk free, mildew free, durable shower and customers who will give me referrals.
Thanks all, for your responses. I guess I did not make clear that this is an existing shower - 35 years old - in a rental house and there is presently a 1/4" gap between the bottom row of tile that overlaps the nailing flanges and the visible rim of the shower base. Sounds like the majority would seal that gap somehow. Grout will likely crack, silicon caulk will turn black with mildew. Maybe the sanded caulk that someone suggested will work.
BruceT
Clean out the gap and give it a final wipe with denatured alchol. Caulk it with silicone or gout matched caulk such as Tec or others. Grouted inside corners, especially with dis-similar materials are a crack waiting to happen.
It has been my experience to do the following: 1. cement board attached with roofing nails and construction adhesive. 2. silicone the corners and silicone between the cement board and the base or tub. 3. Tile leaving no more than an 1/8 and n o less than a 1/16 between base and tile. 4. grout and cross your fingers that there is no cracking. 5. Apply sanded caulk if necessary to any cracking. I try to use minimal to no caulk if possible in the finishing process. As for the initial question in an existing situation I would clean out the base joint and then go step 2, 4 then 5 if necessary.
The 1/4 inch gap sounds a little wide for caulk. In a rental house I would consider filling the gap with epoxy grout. I did this in an old bathroom about three years ago as a temporary fix and the epoxy still looks fine.
Billy
CAULK IT!!!! THAT AND ANY OTHER 90 degree (ie inside corners) Grout is going to FAIL. Mapie products make caulks that match their grouts perfectly. In a perfect world I would tile, caulk, then grout, if timeing is not an issue. A perfect example of 90 degree failure is kitchen counter backsplashes in most cases grout won't last a year. Look in any shower where is the failure, yup, the inside corners and where the tile meets the tub or shower pan.