Grout vs. silicone at change of planes

[Anonymous]

NP: And yet the master bath shower in our new build is 5-6yo. The hairline grout cracks have developed a life of their own. Yes there is a membrane underneath (I saw it all go in) BUT so much water builds up under the tile it “smooshes” out when you step on it like a creaky floorboard.

[Anonymous]

We were told that silicone will fail much more quickly than grout/caulk

[Anonymous]

Anonymous wrote:We were told that silicone will fail much more quickly than grout/caulk

I have several rentals with caulked showers and I would say the silicone starts to deteriorate closer to 15 yrs. Contractors are very set in their ways, so they often tell you bogus info because there is no way in hell they are going to change up their methods and/or materials.

[Anonymous]

We had our shower done almost 3 years ago and have mold on the silicone where the walls and floors meet and it looks awful. It happened 18 months ago so I took out the silicone (such a pain to do) then put new supposedly mold free silicone on. Now the mold is back. It seems to be under the silicone almost. I am going to have to spend winter break removing it and then will put down caulk but no way am I doing silicone again.

[Anonymous]

Anonymous wrote:We had our shower done almost 3 years ago and have mold on the silicone where the walls and floors meet and it looks awful. It happened 18 months ago so I took out the silicone (such a pain to do) then put new supposedly mold free silicone on. Now the mold is back. It seems to be under the silicone almost. I am going to have to spend winter break removing it and then will put down caulk but no way am I doing silicone again.

I
I had the same problem. I suspect water was being absorbed into the stone and then getting behind the caulk? I used this gel and it took care of the mold with barely any scrubbing. I thought for sure it wouldn't work! Amazing!
https://www.amazon.com/gp/product/B099W7DTBH/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

[Anonymous]

Anonymous wrote:NP: And yet the master bath shower in our new build is 5-6yo. The hairline grout cracks have developed a life of their own. Yes there is a membrane underneath (I saw it all go in) BUT so much water builds up under the tile it “smooshes” out when you step on it like a creaky floorboard.

This isn't a grout problem, it's a problem with the underlayment and/or the mortar that was used to hold down the tiles.

For the nth time: grout is not waterproofing. It's not waterproof. Tile is not waterproof. Caulk is not waterproof. Mortar is not waterproof. The expectation is that water will seep through all of those materials. There needs to be a waterproofing layer between the underlayment and the finish materials.

[Anonymous]

It's entirely a cosmetic problem: which do you think looks worse, grout that cracks or caulk that doesn't match the rest of the grout and is more likely to mildew? Because that's the choice.

In my shower I grouted the plane-change joints. After a few months they cracked. I mixed up a bit of the leftover grout powder, filled the cracks, and wiped off the excess with a sponge. A few months later, I did it again. After a while new cracks stopped forming.

[Anonymous]

Industry standard is silicone caulk, not grout.

[Anonymous]

Epoxy grout won't crack

[Anonymous]

Anonymous wrote:

Anonymous wrote:We are getting estimates to renovate our bathrooms, and every contractor we have spoken to (who all came highly recommended on Checkbook) has said that they use grout at changes of planes. This runs contrary to everything I have ever heard/read/experienced; my understanding is that because grout isn't flexible, it is bound to crack in this application. Am I going crazy? If just one contractor would say this I would assume that they are cheap/lazy but everyone I've talked to has said the same thing.

So what I have learned is that silicon prevents the “dripping” of water down at the base of showers and bathtubs so that the hardy board in the back absorbs the water.

We have had a couple of our showers destroyed by this practice already.

This is correct. Use grout it allows the water to go back into tub or shower base.

[Anonymous]

Good info in this thread. That said, if they are doing a traditional shower (as opposed as a Kerdi shower) it is important for the Durock not to touch (let alone be embedded in) the shower pan and be red-garded to avoid capillary action. I'd use silicone (in the shower base only) and be ready to reapply every few years.

I would prefer a Kerdi shower, but the contractor really needs to know how to do it. I'd ask how them how they plan to waterproof and check against John Bridges info.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:We are getting estimates to renovate our bathrooms, and every contractor we have spoken to (who all came highly recommended on Checkbook) has said that they use grout at changes of planes. This runs contrary to everything I have ever heard/read/experienced; my understanding is that because grout isn't flexible, it is bound to crack in this application. Am I going crazy? If just one contractor would say this I would assume that they are cheap/lazy but everyone I've talked to has said the same thing.

So what I have learned is that silicon prevents the “dripping” of water down at the base of showers and bathtubs so that the hardy board in the back absorbs the water.

We have had a couple of our showers destroyed by this practice already.

This is correct. Use grout it allows the water to go back into tub or shower base.

The dripping should happen below/under the tile, from the waterproofed durock toward the shower base. Grout or silicone should be irrelevant

[Anonymous]

Anonymous wrote:

Anonymous wrote:We are getting estimates to renovate our bathrooms, and every contractor we have spoken to (who all came highly recommended on Checkbook) has said that they use grout at changes of planes. This runs contrary to everything I have ever heard/read/experienced; my understanding is that because grout isn't flexible, it is bound to crack in this application. Am I going crazy? If just one contractor would say this I would assume that they are cheap/lazy but everyone I've talked to has said the same thing.

So what I have learned is that silicon prevents the “dripping” of water down at the base of showers and bathtubs so that the hardy board in the back absorbs the water.

We have had a couple of our showers destroyed by this practice already.

Do you know how your showers were constructed? I've installed many showers, and silicone caulk has never destroyed a single one of them. Contractors do a lot of shady things when it comes to constructing showers. I mean, it's insane some of the stuff they try to get away with. There are a lot of different construction methods and you really don't know the cause of the problem oftentimes until you start tearing it apart. One thing I have noticed is that natural stone showers seem to have more problems because they absorb a lot of water.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:We are getting estimates to renovate our bathrooms, and every contractor we have spoken to (who all came highly recommended on Checkbook) has said that they use grout at changes of planes. This runs contrary to everything I have ever heard/read/experienced; my understanding is that because grout isn't flexible, it is bound to crack in this application. Am I going crazy? If just one contractor would say this I would assume that they are cheap/lazy but everyone I've talked to has said the same thing.

So what I have learned is that silicon prevents the “dripping” of water down at the base of showers and bathtubs so that the hardy board in the back absorbs the water.

We have had a couple of our showers destroyed by this practice already.

This is correct. Use grout it allows the water to go back into tub or shower base.

This is so incorrect it's barely even wrong. Grout is cosmetic. The waterproofing has to be behind the tile.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:We are getting estimates to renovate our bathrooms, and every contractor we have spoken to (who all came highly recommended on Checkbook) has said that they use grout at changes of planes. This runs contrary to everything I have ever heard/read/experienced; my understanding is that because grout isn't flexible, it is bound to crack in this application. Am I going crazy? If just one contractor would say this I would assume that they are cheap/lazy but everyone I've talked to has said the same thing.

So what I have learned is that silicon prevents the “dripping” of water down at the base of showers and bathtubs so that the hardy board in the back absorbs the water.

We have had a couple of our showers destroyed by this practice already.

This is correct. Use grout it allows the water to go back into tub or shower base.

This is so incorrect it's barely even wrong. Grout is cosmetic. The waterproofing has to be behind the tile.

You can have water proofing behind, and still have grout, that diverts 99.9% of water toward a drain. Redundancy works.
Grout is not only cosmetic. It can certainly provide a waterproof surface.

The issue is not always waterproofing, it is managing what happens to moisture after it migrates through/around a certain material or surface.