18

Let's look at the three pictures above. #1 - This is probably the most common install. You cement board is on the same plane as the flange. It is thicker so it ends up hanging over. Tip - If you are using cement board by itself I would strongly suggest using 1/2 inch. Also I am a strong supporter of hardibacker since it doesn't allow water through or ...


10

Disclaimer: I am not an expert. I have worked on about a half dozen seperate tile floors, though! These instructions are not meant for a shower wall or floor, just every day use floors like bathroom, kitchen, mudroom, etc. You should also have a decent bit of knowledge on how to use all the tools safely, and a lot of patience/time. This is not as simple as ...


7

The backer should go OVER the flange, for better water drainage. Because the backer board tends to bow out when 'lipped' over the tub flange, you should: Install the tub Install shims on the studs to 'pad out' the backer so that it just clears the tub flange and overhangs it a bit (but doesn't 'land' on the rim of the tub) but leaves a 1/4 to 3/8 inch ...


7

Backer needs to go up at least 5 feet and extend a couple inches out a tub surround and used in all parts of a shower. It only needs to be in the wet areas. For tub surrounds I normally put two horizontal pieces of backer board (goes 6 feet over tub top). Tubs are usually 5 feet in the US and backer is sold in 3x5 pieces. I then put one piece vertically ...


5

Backer board, HardieBacker, or cement board is used on any surface that is to be tiled.


5

If those T&G boards are your subfloor, you'll be fine putting the cementboard panels right over them. Just screw them down to the wood subflooring with plenty of screws; don't use thinset for that. DO use thinset to cover the cementboard seams and screw holes, then tile right over it.


4

For a pure shower (not bathtub), I always put a membrane on over the backerboard. Redgard is my preferred choice right now so I would be fine with that choice. I really don't think there is anything that you need to do. If I am putting plastic behind my backer I should see it sticking out under the backer and over the base in the picture - it would be ...


3

Yes, your plan sounds perfectly fine, initially. But, that deep of a divot for such a small area is concerning to me. I'd take the plywood up or drill an inspection hole in the ceiling below to see what's going on. To me it sounds like it could be 1 of 3 things: 1- The plywood is cracked & therefore compromised, so it should be cut-out & replaced ...


3

When I did my shower, I lined it up so the Hardi/drywall seam was about 1" before the edge of my shower tiles. Then I just covered this seam with mesh tape and thinset. So when I laid tile, it overlaid onto the drywall by about 1". I then used a caulk matched to the grout color run along the outside edge of the tile where it met drywall. The tile edge is a ...


2

You don't have to use a backerboard on shower ceilings - especially if you aren't tiling it. You can drywall it. If you do use a backer board I would suggest Hardieboard. You would then just put a skim coat of joint compound (mud) over and sand.


2

If it's in good shape (clean, planar, etc.), then it is fine to put tile on top of it, assuming that putting tile on it doesn't make the floor too high at the entrance to the bathroom.


2

Depending on what is behind your backer you need long roofing nails. I use HB 30-40 times a year and and I use the HB screws and long roofing nails. For shower walls that are a little tough I will double predrill for my backer screws. I will use a small bit for the hole then I will through each hole and use a larger bit. The larger bit I just give a tap ...


2

This question is either subjective (based on opinion and personal standards of quality) or is a warranty issue. In either case it's probably off-topic. That said, here are my thoughts. Yes, adhering the cementboard sheet to the drywall will add stiffness--probably enough to result in a satisfactory substrate, especially when considering the large size of ...


2

If you have single-layer plywood, you might want to consider Schluter Ditra membrane. It serves as crack isolation and waterproofing: Designed specifically for ceramic tile and dimension stone installations, DITRA serves as an uncoupling layer, waterproofing membrane, and vapor management layer that accommodates moisture from beneath the tile covering. ...


2

1) Safe assumption. Your floor trusses are carrying the load of the entire room. A little extra tile weight isn't going to matter. 2) You want a relatively level surface but the thinset itself will have enough flexibility to allow your final floor to be perfectly level, provided you take the time to make sure each tile is placed level. If your variance ...


2

I see that the floor tile (and possibly the plumbing, a cement bed, or whatever) prevent you from moving the tub. That was going to be my first suggestion. If it's a possibility, do that. Move it only as far as necessary toward the long wall to make it flush with the cement board. Otherwise, I also see that you have the drywall cut back some distance on the ...


2

Some basic comments on what I would do: First I see that you cut out a 18-24 inches beyond the tub. That is fine. But I like to see a 2x4 right where you would put a shower curtain up and another to the far right to help handle the drywall. Flip these 2x4s on their side since you have electric. If your gap is too big then add 1/4" drywall behind backer....


2

DensShield is a Class II vapor retarder (at least, after tiling), which should meet your code requirement (YMMV). I would recommend tearing out the plastic membrane vapor barrier, using only the DensShield. As things are, I think you're probably okay, though. The DensShield will still allow some (though limited) drying for any moisture that makes it in ...


2

What you have is done all the time. In some cases it is set on regular drywall, a little weaker than the blueboard. The loading tests the shear strength of the screws and glue that holds the drywall in place, if it has it. If it was done like that on the ceiling, it would be a different matter.


2

Plywood would be a very good choice. You should consult the ditra literature for your particular joist spacing, however, generally the bare minimum thickness for plywood/T&G subfloor under ditra is 5/8". Plywood in general adds more strength to a subfloor than cement board, and given that you are going over it with ditra, it makes more sense to add ...


2

According to this video produced by Kohler, you should use greenboard or other water resistent backer material. I wouldn't use OSB, and cement board seems like overkill but could help if you needed to stiffen up the walls I guess. https://youtu.be/4-s-pfbj0YU


2

Kohler recommends water resistant drywall or green board. Make sure you have blocking at the height needed if installing things like hand rails.


1

I would let that dry the best you can, heat or fan...once that is done, paint it with kilz or similar and, of course, wait for that to dry, then install backer board up the wall. The reason I would paint the framing is to inhibit any growth of spores you can't get to die completely, therefore sealing them in and causing them to die. Some people seal it, ...


1

OP's comment: "The flooring is coming up next." So this is a gut job. Remove the rest of that wall's drywall and shim every stud with 2x4s attached to their sides, letting them project as needed (a six foot level is your friend here). Drywall is the enemy. Big hole/little hole = same amount of work. Use an 'F' profile style Metal Bullnose Tile Strip. I've ...


1

You need more than a vapor barrier...you need waterproofing. Tile and grout and hardi-backer aren't in and of themselves waterproof. The easiest way to do this is to use Redgard. You put up the backer board, tape and mud the seams, then you paint the Redgard on. This creates a completely waterproof rubberized waterproofing layer behind your mortar/grout ...


1

I would glue and screw down the plywood. If you use hardy backer board I would use a dash patch or leveling compound on that before you set your tile. A good alternative would be to do a mud job on top of the plywood that would take care of the leveling problem. A mud job is tar paper stapled to the plywood with a layer of stainless steel mesh nailed to ...


1

I'd be inclined to add a few roofing nails in critical locations--corners, edges, etc. The nails mostly provide sheer strength, so it's unlikely that you'll see a problem.


1

I hate to tell you that I know from calling the manufacturers of both hardiebacker and durock that they do no support concrete installations. Both indicated that it would probably work fine but they simply haven't tested it. I have personally used it in a very small area that I needed to raise - very small. You want to treat it like tile (thinset with ...


1

If you are removing the backer board, protect the tub (tape plastic over it and perhaps also use something like moving blankets or cardboard to pad it against impact) and use a crowbar and/or sledgehammer (with care not to go through the other side of the wall nor to damage the tub) to gain access for the crowbar to pry the backer-board off the studs. Or ...


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