View Full Version : Why does my contractor want to use sanded grout on a bathroom wall ?

May 9, 2010, 05:53 PM
I am renovating my bathroom. I am using porcelean tiles on the wall the tiles are 12x24
I told my contractor to kiss the tiles so it looks like a solid wall with a one eight grout line
he said the that cannot be done so it has to be a quarter inch grout line and he has to us sanded grout on the wall is that right?

May 9, 2010, 05:56 PM
i am renovating my bathroom. I am using porcelean tiles on the wall the tiles are 12x24
i told my contractor to kiss the tiles so it looks like a solid wall with a one eight grout line
he said the that cannot be done so it has to be a quarter inch grout line and he has to use sanded grout on the wall. is that right?

Do you Use sanded grout on the walls?

May 9, 2010, 06:09 PM
My bathroom is being renovated the contractor insists that he use a one inch grout line between the tiles one the wall in the bathroom and he is going to use a sanded grout on the wall. Will that not leak after a while? Do you use sanded grout on the bathroom wall

May 9, 2010, 08:26 PM
What is size of tile. A 1 inch grout line is very wide. The largest I have seen is 3/4 inch and that was on the floor and 18 inch tile.

It is uncommon to use sanded grout on walls. Will not get a smooth appearance. If grout is sealed will stay clean and not cause a water problem. The wider the tile line the more a chance it will crack over time. There is a grout made that has more elasticity usual grout used.

The larger the tile the larger u can make the grout line and still have it look good.


May 9, 2010, 08:36 PM
The reason he wants 1/4 inch grout line is because sanded grout will not work to well on 1/8 inch.

Don't see any other reason for not putting in an 1/8 inch grout line.


May 9, 2010, 09:09 PM
Unless the tiles are a cheap quality or irregular, I see no reason why he can't set them about 1/8" apart. Are the tiles rectified? Maybe that's why he doesn't want them too close. Large rectified tiles can be a nightmare to set even 1/4" or so apart. Wasn't all this discussed before when he gave you the price or did you surprise him after with your selection? Rectified, large size means he has to charge you more. It that part of the problem?

I would go with sanded grout with porcelain set with 1/8 or wider joints. Why did you question using sanded grout on walls?


May 10, 2010, 07:00 AM
Why did you question using sanded grout on walls?

Jaz, I've noticed there seems to be this myth that sanded is for floors and unsanded is for walls.

apattyd, all tiles will have some amount of warp-age. They go into the kiln one size, they all react to the firing a little different and come out all slightly different. Some might be a little cupped, some a little bowed, some will end up a little bit larger or smaller than the mean. They are sorted within their color lot into dimensional groups referred to as calipers. If they are rectified, they will all be cut/ground to the same size/square but it won't affect the warping over the plane of the tile.

Do this test...

Take two tile, lay them face to face and see how much space you have at one end when you pinch one end down and the other end lifts. Next, lay out a couple tiles next to each other, "kissing" as you put it, in a brick pattern which I'm guessing is the pattern you want it installed. At the joints between where two tiles of one row meet at the mid point of the tile in the row above and below, there's probably an excessive amount of lippage. If the tiles themselves cannot be in a flat plane when you lay them out like that, they won't be able to be in a flat plane when you install them. The larger the tile, the larger the problem and 24" is a large tile. You need a larger grout line to transition between those variations.

Once again, assuming you want those installed in a broken joint pattern, instead of using midpoint spacing, consider 1/4 or 1/3 point spacing. The closer you return them to stacked tile, the tighter you can generally set the joint.

If you did brick pattern with them standing on the 12" side, you might be able to do the 1/8" joint.

May 10, 2010, 07:27 AM
and he is going to use a sanded grout on the wall. Will that not leak after a while?

You have another thread going about this similar thing, but you brought up another thing here that needs to be addressed and that is about grout providing a part of the waterproofing of the tub/shower walls.

Sanded grout is used for joints of 1/8" or more, wall, floor, ceiling, inside, outside, whatever. Grout doesn't care where it's going, it only cares about the size of the joint.

Grout does not perform any function of waterproofing. If your shower or tub surround cannot contain every bit of water prior to the very first tile being installed, it will not contain the water once the tile is installed either.

Construction of the shower walls includes something to provide for the waterproofing, either a moisture barrier of 4-6 mil plastic sheeting or 15 lb roofing felt installed to the framing and overlapping the pan/tub flange or shower pan liner then the cement board-or- a surface applied waterproofing membrane is installed on the cement board, such as a liquid like Hydroban or Redgard or a sheetstyle like NoblesealTS or Kerdi. If none of these options were done, your installation shouldn't be proceeding anyway.

If your installer has built a shower pan for you using a shower pan liner and mud, and you are not using a preformed shower pan or just doing a tub surround, then you also need to be certain these things were done correctly in constructing the shower pan for you. If you are not certain, but you took pictures or could describe the steps, post the pictures od describe the events.

--The shower pan liner cannot be installed flat in the floor. The installer must first install a sloped mud bed so the liner is pitched. There will be 2 mud layers with the liner sandwiched between.

--The shower curb must not be formed by nailing cement board to it.

--No nails in the bottom 8" of walls. If you saw nails/screws in the bottom of the walls before the top mud base was installed or the walls went in after the mud base went in and you see nails/screws anywhere within 5-6" of the bottom of the walls...

--No pressure treated lumber. If you saw any wet, greenish colored lumber used, it will dry out, twist, warp and break apart your tile.

--Knee walls (half walls) and site built niches will require some form of surface waterproofing.

--Benches.. It's amazing to me that some contractors think they can take shower liner, run it up and over a bench, nail through it, and think it's waterproof still.

May 11, 2010, 07:12 PM

You brought it up above about labeling grout for certain applications as apposed to width of space etc.

When sanded for floors & unsanded for walls discussion came up, I would always ask, "what kind would you use on the ceiling?"

I think some old-timers may remember when we only had 4 1/4" soft bodied tiles for walls and either unglazed quarry or mosaics for floors.

We always sold unsanded for soft ceramics and sanded for all mosaics and quarry, (of course). We of course never suggested soft tiles for floors, so floors always got sanded grouts.

Similarly we used to order 2 types of thin set. Back then they made a wall thin set in two colors and floor mix in two colors. We always go the wall mix in white and floor floor mix in gray. Some people still think of it in regards to color not type.