Can I install ceramic tile directly to a cement block wall in the basement?

Question

I am building a shower in the basement of a 50 year old house in Michigan. I am using cement board (backerboard) for the sides which I framed in. The back of the shower is the existing cement block wall. Can I apply the mortar and tile to the cement block wall just as I would for the cement board? Will there be any problems with it stinking? The wall will get chilly during the winter.

Answer 1

Not ideal, but yes you can.  You really do need that concrete board on the exterior wall as well as an air space between the outside wall and the backerboard.  You don't need much, but at least an inch or so.  good luck.

Answer 2

I see you have several answers already, some are adequate I suppose, some are good, one person has the beginnings of what you need to do.  There is no implied criticism or disdain for their comments.

If this project is in a house you are about to sell OR if you really do not give a hoot about durability, then read no further.

To do the job correctly and have a durable finished product here's what you should do:

Install a vapor barrier on the existing block wall, either painted on ( 2 coats ) or applied as sheet poly

Install 1x furring strips at 16" o.c. with foam insulation board between the furring strips

If your tile is going to the ceiling you can omit installing moisture resistant gypsum wall board, otherwise install the wall board from the top of the preformed pan, if that is what you are using, or, from about 1" off the floor to the ceiling.

Install cementous backer board behind all areas to be tiled.

Install your tile and grout.

SEAL the grout with 2 coats of grout sealer after allowing 8 hours between coats.

Answer 3

I don't see a problem with that as long as you make sure you use a high quality water-proofer for the grout.

I installed tile directly onto cement and it turned out well... I just made sure to use a lot of coats of water-proofer.  Mine wasn't in a basement though, which is traditionally more damp and prone to mold, mildew, etc.

Answer 4

Travelingsupervisor is absolutely correct! If you do decide to use that "Dri-lok",though, MAKE SURE YOU WEAR A RESPIRATOR! I cannot stress that enough! It states right on the label that IT WILL cause cancer!!! Be careful!

Answer 5

Do not do this if you want a good long lasting job. Moisture from the shower and vapor from the block work both ways. A plastic liner first attached to the wall then cement backerboard lagged to the wall will give a better result. Not perfect but better.  If you just attach the tiles the vapor that comes through the walls will affect either the grout or the block itself causing it to efforvescence making the bond less strong. Painted areas should also be avoided to attach tiles to. Once again the vapor and water work both ways. Once you get the tiles up really pay attention to the condition of the grout and any cracks that develop along the sides to repair them as soon as possible.

   Also take into account the moisture that you are getting in the basement naturally. Is it a 'dry' basement or do you have water problems. It may be that it would be less hassle to just paint the wall in the shower and be able to maintain the paint than going to all the effort of tiling methods just to have a mold machine.

Answer 6

i dont see y not. the cement board is because the weight of the tile is too much for regular drywall so yeah, just clean it good to get a good bond with your mortar.  use tsp

Answer 7

Sure ! As long as the wall is clean. lf using big tiles 6'' square or bigger, buy a bag of spacers.$3. Big tiles will creep down towards the bottom of the wall from thier weight. Stand back and check them. Good luck !

Answer 8

I think that I'd seal the blockwork first, since the tilework depends on the surface to which it's applied for adhesion etc. You can use UGL "Dri-Lok" waterproofing paint. Use the water base Dri-Lok, the oil base has a fairly powerful odor. The sealing would have 2 benefits - keep moisture from the outside from getting into the house, and keep interior shower moisture from getting into the blockwork.