Bathroom remodel - Durock vs Permaboard

TresK3 Posted By TresK3, Aug 28, 2017 at 3:12 PM

  1. TresK3

    TresK3
    Member 2.
    NULL
    

    Jul 12, 2007
    92
    1
    Loc:
    Cincinnati, Ohio
    In doing the bathroom remodel (referenced on other posts), I'm re-tiling the shower and the floor (basically everything). In past similar projects (about 25 years ago), I used greenboard around the tub and 1/4" luan underlayment on top of the sub floor, for the floor tile. For this project, I'm going with cement board all around.

    I was at Menard's picking up supplies (don't judge me...) and grabbed 4 sheets of 1/2 inch "cement board" to get the floor started. When I got home and unloaded them, I realized that one sheet was Permaboard (it was lighter) and 3 sheets were Durock. Both claim to be 1/2", but without putting a micrometer on them, the Permaboard seems a tad thinner (maybe 1mm). I'm thinking to use the heavier stuff (the Durock) for the floor and saving the Permaboard for when I do the shower.

    However... are there any benefits of one over the other, especially for my applications?

    Also, for the floor, do I need to seal with anything before tiling? I'm assuming that I should use a floor leveling compound at the joints. Is there anything else I should do?

    Thanks!
     
  2. gzecc

    gzecc
    Minister of Fire 2.
    NULL
    

    Sep 24, 2008
    4,496
    880
    Loc:
    NNJ
    Use Redgard on the walls in the shower after you tape the joints. None of the under layments are waterproof. Adds cost and time, but I always wanted my shower walls to be waterproof.
     
  3. sportbikerider78

    sportbikerider78
    Minister of Fire 2.
    NULL
    

    Jun 23, 2014
    1,880
    734
    Loc:
    Syracuse, NY
    Our shower is waterproof and it looked like this before the tiling began. This is cement board (durock) mudded and taped joints. Our guy used something very expensive on it and did 2 coats.
     

    Attached Files:

  4. semipro

    semipro
    Minister of Fire 2.
    NULL
    

    Jan 12, 2009
    3,201
    513
    Loc:
    SW Virginia
    2nd this.
     
  5. vinny11950

    vinny11950
    Minister of Fire 2.
    NULL
    

    May 17, 2010
    1,237
    215
    Loc:
    Eastern Long Island, NY
    For the tile floor outside the shower, if you use the durock as an underlayment, you need to use a cementous mortar in between the plywood and the durock. Then secure it all with plenty of screws. Once that dries, tape the joints with fibertape made for cement boards and fill the seams with more mortar.

    For the shower floor in the shower stall, you need a totally different system to water proof it all. Go to Johnbridge.com and look around.

    You will get plenty of ideas and information on how to build a shower correctly. They have a calculator that will tell you if your floor joists can handle the tiles you want to use. Also, you should have one layer of 1/2 plywood and another layer of T&G 3/4 floor rated plywood. Then you put on the 1/2 or 1/4 of durock. 1/2 is used for the wall and 1/4 for the floors, but you can use the 1/2 on the floor too.
     
  6. TresK3

    TresK3
    Member 2.
    NULL
    

    Jul 12, 2007
    92
    1
    Loc:
    Cincinnati, Ohio
    Just to confirm, I tape the joints with the fiberglass tape, and use Redgard as the "joint compound" and to cover all of the durock. Do you (gezecc and Semipro) recommend one or two coats?
     
  7. gzecc

    gzecc
    Minister of Fire 2.
    NULL
    

    Sep 24, 2008
    4,496
    880
    Loc:
    NNJ
    Think directions state 2 coats . Read container.
     
    semipro likes this.
  8. TresK3

    TresK3
    Member 2.
    NULL
    

    Jul 12, 2007
    92
    1
    Loc:
    Cincinnati, Ohio
    Will do.

    Thanks!
     
  9. Dobish

    Dobish
    Minister of Fire 2.
    NULL
    

    Oct 26, 2015
    987
    461
    Loc:
    Golden CO
    redguard for sure.... just be careful to tape off everything you don't want it on, because once it is dry, it is a pain to get off.. 20150201_004249.jpg 20150210_003239.jpg DSC_0207.JPG
     
    vinny11950 likes this.
  10. sportbikerider78

    sportbikerider78
    Minister of Fire 2.
    NULL
    

    Jun 23, 2014
    1,880
    734
    Loc:
    Syracuse, NY
    You use mortar on the joints and tape them. Then you seal it all with what ever waterproofing you have.

    That is how the guy that built my shower did it. It looks perfect.

    He also used a waterproofing membrane under the durock from the floor/base to about 2-3' up into the shower wall. This is an added layer of insurance.

    Depending on the tile, it can realllllly matter if your wall is straight. For small subway tile, its really obvious if your wall is screwed up after you tile it. Use an 8' level to see what your wall looks like. Mine was 3/8 out from top to bottom and required at least 3 bags to level out. Took him an entire day to get right.
     
  11. Dobish

    Dobish
    Minister of Fire 2.
    NULL
    

    Oct 26, 2015
    987
    461
    Loc:
    Golden CO
    i agree! you really see the variation with small tile! Those 3-4 tiles that are just a hair out really bug me, because i said "oh, that will be good enough"
     

Share This Page