OK, quick and easy question ( I hope).
Building surround for drop -in whirlpool, walls up. Soon to attach the 3/4 plywood & 1/2 cement board on top. Question to those more experienced: Should I use the 1/2 cement board or use 1/2 hardie backer? Is there really much of a difference?
Originally Posted by clapfc
I like cement board more than Hardie Board.
What type of waterproofing approach are you using for the tub deck? Any???
Thank you for responding. Interesting question for tub deck waterproofing. I have two bathroom guide books and neither one talks about waterproofing the tub deck. I was just going to use cement board and then tile. I had no waterproofing plan. If you have a suggestion for waterproofing I would love to hear it. In addition I just built the shower bench and was going to cement board on that. Should I water proof that also?
I have three things going on which I will post pictures of.
1.Whirlpool as one walks into the bathroom. I finished the tub frame but did not cut it out yet as I was using the tub frame top (plywood) to put my ladder on has I construct the top of the wall for the walk in shower right behind it. Should I cut out & then waterproof? what should I use?
2. On top of that shower wall I built I left a triangle opening (it is a catheral ceiling bathroom) where I am putting 3/8 inch tempered glass to maximize the sky light over the shower.
3. Shower bench I just finished yesterday. I still have to re-wire most of the electrical lines.
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Any tile installation that will have significant water exposure needs to be waterproofed. If the guidebooks you've been using
somehow omitted that fact, you'd best chuck them in the dumpster right now. There would be some latitude on the
whirlpool, but certainly not for the shower bench. As for the cement board vs Hardiebacker, that's mostly a personal
preference, and a lot depends on the installation details, which I note you completely omitted.
Cement board isn't destroyed by water, but it is by no means waterproof. A properly built shower can be used even before the tile is up and not leak...the tile is the wear/finish layer, NOT the waterproofing layer. Having a wooden shower bench inside of the shower is just asking for problems. You have to waterproof OVER it so it is functionally OUTSIDE the shower (like the studs), if you want it to last (and remember, CBU is NOT waterproof). There are various ways to do this: sheet membranes or paint/roll/trowel on waterproofing systems. It must be done properly and not be haphazard. If you try to wing it, it will probably fail. ALso, keep in mind that the top surface of the bench that is waterproofed, must slope towards the drain and can't be level or it will pool water and fail. At the least, water will keep the grout dark and promote mold growth. The slope is critical as is the waterproofing. There are a couple of industry standards that describe ways to do this correctly; one of them is the TCNA handbook (Tile Council of North America). They are not all that DIY'er friendly, but they do describe various approved, tested methods on how to do things in tile that work. The handbook does not mention product brands, only methods, so you then have to choose a method and then the product to use.
This tub deck was built out of nothing but plywood. I tried to cover it but the builder did not want anything done different.
When he was not looking I coated it twice with Prim Grip from Mapei and then gave it three coats of Hydro Ban.
Not the best approach but better than nothing.
In a perfect world you would install your cement board over your ply with thinset and roofing nails. Then two - three coats of Hydro ban or equivalent. Of late I'm loving the Ardex 8+9 and this could easily go over the cement board as well.
I want to thank everyone for responding and helping me avoid a costly mistake. My plan was to do the shower area with the Schluter system. As such I have decided to use the Kerdi membrane on the tub deck and the shower bench. If I have the sequence right; thinset on the plywood, then the cement board with roofing nails, more thinset on the cement board, then Kerdi and then tile.
Just as a side note, in the current project I ripped out the 3x3 shower and a hugh 6x6 whirlpool the builder installed 25 years ago. There was no cement board anywhere in the bathroom and no waterproofing that I could see. The tile on the tub deck was glued directly to the plywood and directly on the 2x6 boards they used for steps.
I forgot to mention: the shower bench is 14 inchs wide with a 1/4 tilt towards the drain.
SOme people end up splashing lots of water, then consider the house and the humidity levels, and how often the thing is used. A soaker used maybe once a week isn't exposed to much moisture. A shower, on the other hand, might get used multiple times a day. But, industry standards show proven construction methods that work in any environment and last.
It is always something!
Sunday took the Jacuzzi out of the box to install & almost did without testing it. Decided better & tested on driveway in 31 degree weather with cold winds and light snow. Filled up with garden hose & turned on. Looked good except for one jet that was hard to see. My wonderful wife rolled her sleeve up and stuck her hand in the freezing cold water to feel the jet and it was weak. Further examination disclosed the factory installed hose that carried water to the jet was kinked preventing adequate water flow. Back to the store it went.
Morale of the story? Follow the instructions and test before you install.
In one of your future remodeling bouts, you might consider one of the hose bibs that can give you hot and cold water...at least a couple of companies make them, Moen and Woodford among them. It makes it much nicer doing things when it is cool/cold outside. Wash the car on a fair winter day with warm or hot water, for example, or fill your tub to check it out!