Installing Tile in Bath/Shower - Questions Before I get started
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Installing Tile in Bath/Shower - Questions Before I get started
Hello,
I am working on replacing the tile surrounding my bathtub/shower. I have removed my tile as well as the previous backer board. I am to the point where I am going to install backer board as well as do the waterproofing. My tub has a sloped flange rather than a 90 degree angle as I have seen in many descriptions on line. I included pictures that show this as well as my hand drawn diagram.
I have spent a lot of time reviewing all kinds of information on approaches for types of backerboards(including foam), waterproofing systems, as well as trying to find scenarios that match what I have. What I have below is a merging of everything I read and took notes on. I wanted to have another set of eyes review my plans as well as answer a couple of questions.
Installation
1. Overall approach is to use ½” Hardie Backer and using a Liquid Waterproof such as Hydroban. I plan on using using subway tile.
2. Leave a 1/8 inch gap between backer board pieces as well as at corners for movement
3. Install with corrosion resistant screws every 8-12 inches
4. Install furring strips to account for 7/8” thickness of drywall/backer that was removed.
5. Leave ¼ inch gap between board and tub deck, have backer board hang slightly over tub flange (see hand drawing)
6. Apply silicone caulk in the ¼” gap between backer board and tub deck
Waterproofing
1. Place 2” painters tape on tub deck to protect it
2. Apply waterproofing to the very bottom side of the backer board. The ½” edge that faces the tub deck by the silicone caulk that was applied during installation
3. Apply waterproof to the bottom edge of backer board and corners and while still wet apply 6” fiberglass mesh. Have the piece along the bottom edge hang down slightly below the backer board.
4. Use the fiberglass mesh around the valve hole as well as the tub spout and shower head pipes.
5. Follow direction and apply # of coats based on directions.
Questions
1. Installation and Waterproofing – Do my steps above look good? Missing anything?
2. Waterproof application – Does adding an extra coat beyond what is called for cause any issues?
3. Caulking – Step 6 of my installation – I seem to see people doing this in the “How To’s” on line. Does this make sense, as it feels like I am just trapping any moisture there happens to be at this point?
4. Silicon at corner of backer board - - Saw a site that talked about using Silicon at corners instead of Mesh tape to allow for movement? Feels risky or is that common?
5. If the tile is not going to go all the way up to celling, should I use regular drywall or greenboard on this portion of the wall? Or DensShield?
6. Ceiling of tub/shower area - The ceiling above my tub/shower is dropped, you can see in the picture. I was thinking about not going all the way up to this dropped ceiling just because I fear I am going to have to end up cutting the horizontally in order to get it to squeeze in at the top. Did not think would look good or is that normal to do? I was thinking I would end up leaving a 4-5 “ untiled gap at the top with the benefit of being able to have a full tile at the top.
7. Has anyone used GoBoard from Johns Manville? It appears to be more affordable version of Wedi. They both are closed cell products, but not sure of other technical comparisons.
GoBoard - https://www.jm.com/content/dam/jm/gl...ard%20FAQs.pdf
Wedi - http://www.wedi.de/fileadmin/media/d..._rz_SCREEN.PDF
Thanks for the help before I get started moving on this.
Paul




I am working on replacing the tile surrounding my bathtub/shower. I have removed my tile as well as the previous backer board. I am to the point where I am going to install backer board as well as do the waterproofing. My tub has a sloped flange rather than a 90 degree angle as I have seen in many descriptions on line. I included pictures that show this as well as my hand drawn diagram.
I have spent a lot of time reviewing all kinds of information on approaches for types of backerboards(including foam), waterproofing systems, as well as trying to find scenarios that match what I have. What I have below is a merging of everything I read and took notes on. I wanted to have another set of eyes review my plans as well as answer a couple of questions.
Installation
1. Overall approach is to use ½” Hardie Backer and using a Liquid Waterproof such as Hydroban. I plan on using using subway tile.
2. Leave a 1/8 inch gap between backer board pieces as well as at corners for movement
3. Install with corrosion resistant screws every 8-12 inches
4. Install furring strips to account for 7/8” thickness of drywall/backer that was removed.
5. Leave ¼ inch gap between board and tub deck, have backer board hang slightly over tub flange (see hand drawing)
6. Apply silicone caulk in the ¼” gap between backer board and tub deck
Waterproofing
1. Place 2” painters tape on tub deck to protect it
2. Apply waterproofing to the very bottom side of the backer board. The ½” edge that faces the tub deck by the silicone caulk that was applied during installation
3. Apply waterproof to the bottom edge of backer board and corners and while still wet apply 6” fiberglass mesh. Have the piece along the bottom edge hang down slightly below the backer board.
4. Use the fiberglass mesh around the valve hole as well as the tub spout and shower head pipes.
5. Follow direction and apply # of coats based on directions.
Questions
1. Installation and Waterproofing – Do my steps above look good? Missing anything?
2. Waterproof application – Does adding an extra coat beyond what is called for cause any issues?
3. Caulking – Step 6 of my installation – I seem to see people doing this in the “How To’s” on line. Does this make sense, as it feels like I am just trapping any moisture there happens to be at this point?
4. Silicon at corner of backer board - - Saw a site that talked about using Silicon at corners instead of Mesh tape to allow for movement? Feels risky or is that common?
5. If the tile is not going to go all the way up to celling, should I use regular drywall or greenboard on this portion of the wall? Or DensShield?
6. Ceiling of tub/shower area - The ceiling above my tub/shower is dropped, you can see in the picture. I was thinking about not going all the way up to this dropped ceiling just because I fear I am going to have to end up cutting the horizontally in order to get it to squeeze in at the top. Did not think would look good or is that normal to do? I was thinking I would end up leaving a 4-5 “ untiled gap at the top with the benefit of being able to have a full tile at the top.
7. Has anyone used GoBoard from Johns Manville? It appears to be more affordable version of Wedi. They both are closed cell products, but not sure of other technical comparisons.
GoBoard - https://www.jm.com/content/dam/jm/gl...ard%20FAQs.pdf
Wedi - http://www.wedi.de/fileadmin/media/d..._rz_SCREEN.PDF
Thanks for the help before I get started moving on this.
Paul





#2
Welcome to the forums Paul - sorry for the delay in answering your question, we have been experiencing log in issues which has kept many off line. Those issues have been corrected so you should see more responses.
It is always easier for a novice to transition to a bullnose tile to cap your walls if you don't have the right equipment such as a wet saw to make your cuts. I will usually tear out the drop ceiling to make it seem more airy and provide better ventilation of the moist air during your shower.
I have never waterproofed the bottom of cement board - seems like a useless step you as are stopping the cement board short and bridging the gap with tile so little chance of water wicking up. Also, you install the cement board and then use a fiber tape embedded in thinset for the corners and seams. Kind of like you would finish drywall except you are using thinset instead of joint compound. Then paint your redgard over the top of everything.
Now is the time to update your plumbing diverter if you haven't already planned that.
Not sure I understand the furring strips at this point, can you elaborate?
No need for mesh tape around the supply and tub spout, those areas will get caulked when you install your finished trim pieces.
Lastly for this post, lay your tile on the floor with spacers and take precise measurements to the start of each next tile - it will be a story board of your tile layout. Use those measurements to figure your final install and how much material to buy. It can also help with placement of plumbing fixtures so that you don't have to drill a hole in the center of a tile and all those elements fall on grout lines. Think about placement of soap dishes and grab bars and such. If using grab bars now or in the future install wood blocking in the wall cavity now that the walls are open.
It is always easier for a novice to transition to a bullnose tile to cap your walls if you don't have the right equipment such as a wet saw to make your cuts. I will usually tear out the drop ceiling to make it seem more airy and provide better ventilation of the moist air during your shower.
I have never waterproofed the bottom of cement board - seems like a useless step you as are stopping the cement board short and bridging the gap with tile so little chance of water wicking up. Also, you install the cement board and then use a fiber tape embedded in thinset for the corners and seams. Kind of like you would finish drywall except you are using thinset instead of joint compound. Then paint your redgard over the top of everything.
Now is the time to update your plumbing diverter if you haven't already planned that.
Not sure I understand the furring strips at this point, can you elaborate?
No need for mesh tape around the supply and tub spout, those areas will get caulked when you install your finished trim pieces.
Lastly for this post, lay your tile on the floor with spacers and take precise measurements to the start of each next tile - it will be a story board of your tile layout. Use those measurements to figure your final install and how much material to buy. It can also help with placement of plumbing fixtures so that you don't have to drill a hole in the center of a tile and all those elements fall on grout lines. Think about placement of soap dishes and grab bars and such. If using grab bars now or in the future install wood blocking in the wall cavity now that the walls are open.