getting ready to put up wonderboard in my shower remodel and thought it might be a good time to insulate. is this a good or bad idea. would it trap moisture inside the walls? should there be a barrier between the insulation and wonderboard?
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should there be a barrier between the insulation and wonderboard?
yes.
It's Never Too Late To Become
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thank you for your input. would felt paper be the correct barrier to use between the wonderboard and insulation in a shower? if so, what weight? if not, what would be the correct product to use?
thanks, brie.
...............I guess everyone's away for the w/e.
Many use t paper, I suppose 15lb would be fine, perhaps 30 lb would be better. Plastic will work, but it will probably deterioate over time.
No paper on the insulation.
There are products applicable to the substrate that negate the need for the vapor barrier.
You will need to take into consideration the thickness of the shower pan membrane (if used) in order that the substrate lies flat on the studs.
There are several decent books out there......Micheal Byrnes is one.
Good luck.
EricIt's Never Too Late To Become
What You Might Have Been
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You are always going to need a membrane between moisture and structure.
Anything cement based must be presumed porus and will absorb moisture.
thank you all. i found something called Aquabar 'B.' in the tile section at hd. has anyone used it?
is green board a better product to use in the shower instead of wonderboardor hardie board? would using greenbaord by pass having to put a moisture barrier between the cement board and the insulation?
thank you again.
Do NOT use so called 'green board'.
I repeat..............
If you are looking for a product that is a little easier to use, I have confidence in Denshield.
Properly installed and detailed, I would use thinset on the first three feet of tile then use mastic.
Why do you ask questions at HD? If anyone there had an inteeligent answer and some usable information they would not be working there.
Get a book or hire a pro. Tile work is not all that hard to do...............but it is real easy to screw up and end up ripping out in 5 years after it has leaked through you dining room ceiling.
EricIt's Never Too Late To Become
What You Might Have Been
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Are you on the left or the right in your pic.
Those guys are the loves of my life................now fully grown and young adults!
Little me is on the right!
The ham on the left is Jeff. That kid kept us all in stitches for many years.
Thanks for asking.It's Never Too Late To Become
What You Might Have Been
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hi there eric, i absolutely agree about hd... notice i said i 'found' something there, let me clarify that it wasn't through asking anyone. i've done quite a lot of tiling very succesfully in 2 of my homes. this is my first enclosed shower, so i'm going to you guys for your experiene and expertise. i appreciate all the info i've gotten. thank you.
In waterproofing you work from the bottom up. So first talk about your shower pan.
i found an fhb article on building a leakproof shower pan using 'chlorinated polyethylene 40. i may do that work myself, or have it hot mopped. haven't decided yet. i've built up the 'inside' of the studs to support either method of waterproofing the pan. the original outside wall (not water) had 3/4" of plaster which i have to build up to, to meet the profile of a window. i can shim above, the same depth as the membrane, then lay wonderboard on top of both. with the walls open, i'm considering insulating, but not at the expense of creating a moisture trap. the article i read advised that the wonderboard on the upper walls get put in before the pan work - less walking around on it. of course, one issue seems to create another so i'm asking a lot of questions trying to hedge off as many mistakes as possible. thank you for your input.
Brie,
Any type of cement backer board will work well behind tile. Hardie is more uniform in size and easier to screw the framing (using proper screws...) than wonderboard, but I still use a lot of WB.
Don't even think of using greenboard of mastic in a shower. Other opinions may vary, but to me cement board goes in wet areas (showers, tub surrounds) and greenboard, if you want to use it, can go elsewhere in the bath...but not in the wet areas. Over the cement board use thinset with tile. Always thinset in wet areas. Mastic can be used in fry areas.
Greenboard is moisture resistant, and mastic is water soluble.
Between the cement board and the framing? Yes, you want someething there if you are going to tile right on the cement board. Cement board is pourous. If it gets wet, water may pass through it...but water will not cause it to decay.
What to put betwween the CB and the framing? Tar paper works. Plastic works. Anything that will keep moisture off the framing.
Now someone mentione Kerdi. Eric? Kerdi is a membrane that gets thinsetted to the shower side of the cement board. Kerdi is a waterproof membrane. Then you thinset the tile to the Kerdi. In this case the Kerdi is the moisture barrier.
Insulation? Sure, insulate the wall cavities. If it's an exterior wall it's required. If it's an interior wall it'll provide a little sound attenuation. Why not?
CPE for the floorpan can be used. I'd choose that over hotmopping. Or take a look at Kerdi and Kerdi the whole shebang. You have to be good to built a decent showerpan. You have to be just as good to Kerdi.
Kerdi is advertised as being able to go over drywall. Regular drywall, believe it or not. Still, I'd use cement board.
Remember, this is not an area for shortcuts, or a place to save a buck.
thank you so much for your detailed response. it's very helpful. i'll check out 'kerdi' but i'm pretty comfortable with cement board and thinset - so i'll probably do that. i'll continue look into what the best type of moisture barrier is. once again...thank you.
Brie,
Try this as a follow-up:
http://www.johnbridge.com/vbulletin/showthread.php?p=177782#post177782
There are myriad links on the first post of the thread, and follow-ups later in the thread. Should keep you busy for a while.<g>
I think somewhere either in that thread or on the forum John had a link to Byrne's JLC article several years ago about making a shower pan. It was a very nice article, well-written and lots of pics for people like me. If you don't find it, email me with your home/work email addy (can't add atttachments to email through prospero) and I should be able to attach it to an email back at you. I'm fairly certain I have it somewhere...
I'm with you on thinset and cement backer board. Dependable.
Is your shower on an outside wall? Is the "wet wall" an outside wall? If both are no then you do not need to insulate. Ask at Johnbridge.com and they will tell you: 1. No greenboard. 2. No mastic. 3. Consider Kerdi on the surface of the Hardibacker rather than "water proofing behind the concrete backer (Hardibacker or whatever brand you choose).