I am buying a new bathtub that has a tile flange on 3 sides.
I plan to install cement board on the walls around the tub. I have been told the cement board should overlap the tile flange and hang down almost to the tub level, then tile goes over the cement board, then caulk from the lower edge of the tile to the tub top.
My question is that it seems to me placing the cement board (and then the tile) over the tile flange will cause that part of the board to be “away” from the wall a little and therefore not flat against the wall. Or does the thinset take up for it?
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I put 1/8" furring strips on the studs.
You can do it without the strips but you get that little kick out at the bottom.
Have two trips scheduled for NOLA - 11/09 and 3/10 - I'll keep you posted.
Jim
Never underestimate the value of a sharp pencil or good light.
Great deal on the trips south... keep me posted.
Do you still have the same phone #.. ending in 1710 ??
I drunk texted everyone in my phone last week when LSU won the CWS....... yours was one of the ones that came back with an error message. So did a few other to valid #'s so I wasn't sure.
cajun problems are off topic!!!$$$###^^^
cajun problems are off topic!!!$$$###^^^
NOT
Just wait till the Revolution....... We're gonna have the rest of the country eating red beans on Monday and fried shrimp on Friday.
AYEEEE............
IF the planned tile is small like a mosaic on sheets or something similar:
I usually make a relief in the back side of the cement board with a diamond blade on a grinder to allow the cement board to clear the tub flange.
IF the tile is large - 6x6 or larger - I just stop the cement board before it gets to the tub flange and let the tile cantilever over the tub flange.
In either case, the tile ends a "grout joint width" before the tub top and that joint gets caulked with the tub full of water. Tub stays filled for at least a day.
Caulk compresses better than it stretches -- I don't care what the ads claim.......
FWIW, I like 1/2" PermaBase on tub surrounds.
Jim
No matter which method you use, shimming, butting, or rabbetting, you need to use a vapor barrier(6 mil poly) behind the cement board, that is what will prevent any water from getting behind the backer.
As an alternative, you can use Densshield tile backer, instead of cement board, then there is no need for a vapor barrier, and it's a lot easier to work with than CBU's
Geoff
This picture of poly behind tile shows that condensation behind the poly is a feeding ground for mold. Roofing felt is a better choice.
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A La Carte Government funding... the real democracy.
because? It breathes some?
I believe the temp/humidity differences of the two sides causes the water vapor in the wall to condense on the back (out)side of the poly... especially if it is on an exterior bathroom wall.
Tar paper accepts/releases water gradually and is not a suitable surface to promote mold growth. A La Carte Government funding... the real democracy.
All the more reason to use Densshield !!
Why is felt any more water resistent than 4-mil poly?
It isn't, that's just a good example of a poor installation of the vapor barrier, It's certainly not condensation either. There appears to be no VB on the front wall, and that is probably where the water infiltrated from. Poor installation doesn't argue for/against a particular method
Geoff
P.S. The VB is required by the manufacturer's of CBU's or the warranty is voided due to improper install
Edited 7/2/2009 7:03 pm ET by Geoffrey
Edited 7/2/2009 7:04 pm ET by Geoffrey
Tar paper absorbs/evaporates water as conditions allow...
condensation doesn't form droplets.A La Carte Government funding... the real democracy.
I've done it all kinda ways with nice results. Sometimes I've used shim shingles (undercourse) cut so the fat side is about the same size as the thickness of the flange and nail it to each stud butting the top of the shingle to the top f the flange and then screw my Hardi to that wiith 30# felt paper behind the Hardi. It does flair the tile out a hair but sometimes I kinda like that. It's barely noticeable and I usually squish the tile a bit deeper into the thinset at the very bottom so the flair is hardly noticeable
http://www.cliffordrenovations.com
http://www.ramdass.org
"No matter which method you use, shimming, butting, or rabbetting, you need to use a vapor barrier(6 mil poly) behind the cement board, that is what will prevent any water from getting behind the backer".
...Baloney
Not so bluntly, but yah, if you have a poly sheet hanging behind the tile underlayment, any water or water vapor that reaches it will run to the bottom of the sheet and drip there.
Again, baloney.
There's no need to waste the time or money installing a poly sheet.
I've done a ton of bathroom tile jobs without doing that and never had any problems.
Any water that might posibly breach the tile / grout will be minimal, and hardly enough to breach / leach through a sheet of cement board or backerboard.
agreed.
You might be able to get away without waterproofing in a tub-only situation, but hopefully you are not installing tub/shower or shower tile without waterproofing. Tile, grout, and CBU are not waterproof.
"Tile, grout, and CBU are not waterproof"
Maybe not, but they're perfectly fine for both shower and tub installations. I haven't had any call backs or leaks on the stalls or tubs I've done without poly / tar paper barriers.
I mean we're not talking about filling up a shower stall all the way like a fish tank are we?
What's the difference between a tiled shower stall and a tiled tub? They both get the same amount of "splash" while in use.
Like I said twice now, it's a waste of time, unless the customer specifically wants me to use it, but if it's up to me, no way.
We have cement board these days which holds up fine against what little amount of water might creep back there. Before there was cement board there was "green" board, remember that? That's the stuff that would get wet and fall apart and that's where you would definitely use a vapor barrier.
What you're advocating is entirely contradictory to tile industry standards. I go with surface applied waterproofing over CBU in any tub or shower install. Poly behind CBU is not a good detail. A good percentage of the work I get is partly or completely the result of someone else's inadequate installation years ago. If you are sure of your methods then I would post them at johnbridge.com and see what feedback you get.
Is a "vapor" barrier the same thing as "waterproofing"? No.
What you're talking about is waterproofing, whole different ballgame.
So what you're telling me you do, for every wet location tile job, is after you install the CBU's, you install a "trowel applied urethane membrane"?
You set the membrane in a bed of "setting liquid" and once that dries you put another layer of setting liquid and then you tile over that?
I hope you get paid extra for that, I know I sure would want to.
Well... I sell a state of the art product, I install same, and get paid for it. Every tile installation is done per the tile council handbook's approved details, and per the manufacturer's instructions. Agreeing to do less makes no sense to me, business-wise. I would like to be known as the most thorough, most expensive, most able to handle complicated jobs.
Why not use Schluter's Kerdi right over some gyprock? No need to use a membrane under Kerdi, which is an awesome membrane itself.
Melcer Tile Co., among others, sells Schluter products in Charleston. There are great installation videos on YouTube showing how to do it.
Go to the John Bridge forum and see what everyone is saying about tiling tub surrounds with this as the prep.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
Edited 7/1/2009 8:59 pm ET by Gene_Davis
Mike,
And when's the last time you opened up the wall behind the tile to see if there is any water damage/intrusion?
Some damage is hidden for years, even decades, before being discovered. When you finally do open up a wall the hidden damage is usually far worse than what was visible from outside the wall.
"Any water that might posibly breach the tile / grout will be minimal, and hardly enough to breach / leach through a sheet of cement board or backerboard."
CBU's are porous and will wick water to the studs/insulation. Look at the photo "Hackinatit" posted, obviously you're wrong on that count.
Geoff
No, I'm not wrong, you're wrong
What does everybody do at the very most bottom of the tile where it meets the tub? They caulk it.
If any water happens to get behind the CBU (by means of wicking) where will it drip down to? The tub flange, and from there where does it go?
Tar paper or no tar paper, any water getting behind the CBU will "dead end" in the same spot unless you are leaving "weep" holes and who does that? Nobody does that.
Like I've said now three times in this thread regarding vapor barriers behind the CBU's .....it's a waste of time.
You ARE wrong, and you're oversimplifying the whole thing. There are plenty of installers who put poly over the studs and over the tub or pan flanges, install the CBU, install the tile, and GROUT the bottom joint. It doesn't trap water that way. If you caulk it with latex tile caulk, and there is much moisture back there, it will eventually re-emulsify the caulk and it will start popping out. You can continue doing wet areas with no waterproofing--and it sounds like you are--but understand that basically the entire industry is lined up against your position. It's too bad, because you could easily be using a material like Redguard or 9235 and be doing an industry-standard job.
If you grout the bottom joint what happens? It cracks due to movement between the tub and the walls. This is not good and will generate a callback. Most of the tubs I install are plastic / fiberglass. The only solution here is to use a mildew proof silicone which allows flexibility. Unfortunately, the silicone also creates a "dam" of sorts which will trap any water that might get behind the tile (or CBU) from properly draining out.
So I still think it's a waste of time. I'm sorry, but I'm not losing sleep over possibly moldy studs decades later. The type of CBU I use is called "hardibacker" and it's virtually non-porous. This stuff doesn't wick / absorb any water at all. And I think what is getting overlooked here is that any water that is going to get behind any tile will first cause damage to that specific tile, by loosening it, follow me? Whatever water that has breached past a grout joint will first, re-activate the mastic and cause the tile to come loose. I would rather spend the time sealing the grout joints verses stapling tar paper.
HardiBacker does absorb water.
The James Hardie installation instructions refer you to your local building codes regarding vapor barriers/retarders.
Thinset, not mastic, is the proper tile adhesive for wet surface applications.
Water gets through the entire grout/thinset/cbu assy regardless of grout sealing and that water will condense on poly film. The roofing felt is the final defense to protect the framing from that water. It also absorbs/releases condensation (no droplets) when the warm/humid inside air is met by cold outside air inside the wall.
A La Carte Government funding... the real democracy.
Mastic is perfectly acceptable for wet surface locations. C'mon. The can's even say so. How is it that my tile has still been stuck on the walls in my showers all these years now? Now you guys are really getting wacky on me.
I'm still not worried about the slight possibility that my framing / studs will get some mildew on them decades down the road. Decades down the road another home owner will want different tile.
And you're the forth person in this post I've been defending myself against, in my opinion, you're four guys using outdated methods trying to justify your wasted time.
I want every single one of you to do the following excersice: grab a scrap piece of your favorite half inch CBU (any manufacturer). Hold it vertically, now spray it for a 15 -20 minutes straight and let me know how much water comes through the other side, then get back to me.
>>Mastic is perfectly acceptable for wet surface locations
It keeps getting better....
Schluter Kerdi, Schluter Dilex transition piece, shown here. Look close. No grout, no caulk.
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Why do it any other way?
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
Here is the cross section.
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View Image
"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
Gene,
that looks like a great system, one question; it appears the initial layer of Kerdi goes behind the tub, then there is a second strip/layer that goes out over the tub flange, then the Dilex is installed on top of that last layer of Kerdi, Is it OK to have the first layer go out over the flange or is there a need to do it in two layers? Thanks for the info!
Geoff
Kerdi is sold in a couple of different widths. I think the detail drawing assumes that you have first put a large piece on the wall, then installed the tub, then used a narrow strip that's easy to handle to make the transition to the tub. I don't think you'd absolutely need two pieces.
Thanks Dave!
Reason I ask is I haven't used Kerdi (only Ditra) and therefore not familiar with it's thickness, the layering seems to create a little bit of a kickout, which isn't bad in itself if not to severe.
Geoff
Geoffrey,That's exactly what I do. I hang the kerdi on the wall and overhang the flange by an inch or so. I put a bead of sealant on the tub flange, then embed the Kerdi into the sealant, then use a blade to cut the Kerdi to length.
What you see in the pic is the Kerdi membrane on the wall. Kerdi is 8 mils thick, or about half a 64th of an inch.
Schluter makes a similar membrane they call Kerdi Band, and it is sold in strips of various widths, like 5", 10". Coiled up. Kerdi Band is only 4 mils thickness, and is more flexible than Kerdi. Kerdi Band is for joint work such as this.
If you go to Kerdi training, the pros from Schluter will be using Kerdi band for that second piece you see in the photo and in the section, the one that laps onto the wall, and a little out onto the tub lip.
Some installers take a short cut, and cut strips of the 8 mil Kerdi to use there instead.
Applying Kerdi materials is very much like installing wallpaper, with the exception that you put the glue on the surface first, in the form of thinset, applied with a toothed trowel.
Go to the website and see the installation videos there. Also, go on YouTube, where there are plenty more videos showing installation.
View Image
"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
what keeps water from getting thru the vertical corners of a tile shower stall. i know thinset in mesh is there but does the thinset crack over time?
Went to Depot today, a sign hanging on the shelf by the backerboard has a list of "Answer and Questions". Reading down the list, a question reads, "is a vapor barrier needed for wet wall installations", the answer is, " A VAPOR BARRIER IS NOT REQUIRED UNLESS BUILDING CODES CALL FOR IT".
I'll take a picture of it Monday and post it.
The cans of mastic that I use say "suitable for wet locations". Of course this is not for all tiles, we're just talking ceramic for this discussion. For stone you'd definitely use thin-set.
Oh and one of the cement boards by Custom Building Products (I think it's Durok) offers a lifetime warranty if you use there product, makes no mention of having to use a vapor barrier.
Building codes are minimum standards....and the minimum is the way you do things so have fun!If you want to educate yourself and learn the right way you should check out http://www.tileusa.com for information and training about how to be a tile setter and not a hack.
I do things the right way, trust me. I totally stand behind my work. I'm not offering sub-par workmanship and I'm not doing my customers a disservice. The Hardibacker CBU's I use DO NOT require a VB. Saw it today with my own two eyes.
My tile jobs will last the same amount of time as yours, or any other tile setters.
If the MANUFACTURER says you do not require a VB, then guess what, you don't need one.
Thanks for the link, I'm sure I'll pick something up, there's always something to learn right? I mean didn't I just teach you something?
So along the same thought process if you had 2x10 floor joist spanning 14' (to code) you would still put down slate or travertine on it then because the code says it's allright?
Sorry, you lost me. Hey wait...is that a trick question! NICE try!
TRUST ME, I'm all for code. I'm ALL for doing things the right way.
(I think this turned into my most favorite thread)
YOU'VE ALL BEEN PUNK'D!!
No, but seriously, do I have to go research every single towns building codes regarding VB's if the job isn't getting inspected and the manufacturer says that VB's are NOT required?
Mike you are the Punk.... go get an education on how to lay tile the right way!
Building to satisfy code is like doing the minimum to pass the course.
"I build to code."
Congratulations. Your grade is a D-.
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"A stripe is just as real as a dadgummed flower."
Gene Davis 1920-1985
Gene, are you now with the other guys who have been piling up on me?
Gee, I was gonna give you a nice compliment on the photo you posted.
My work is all A plus sir and will last just as long as everybody elses here.
I research stuff, buy books, subscribe to FHB, participate here in the forum, I follow codes whenever I'm supposed to. I get paid and I sleep at night.
C'mon Gene, don't give me a D-, that hurts, I thought you were better than that.
I'll say it again, if you feel sure of your methods, post them at johnbridge.com and post a link to the thread here.
Dave, the manufacturer (for Hardibacker) says you don't need it, how much more does anybody need to know? Don't you think that they've had some type of testing prior to making that statement? YOU go post it on Johh Bridge since it seems to bother you so much. I mentioned in an earlier post on this thread, I've opened an older install to replace a faucet, and there's no moisture, or discoloring, or anything to make me think that a VB was required.
follow codes whenever I'm supposed to
you relize what you said here???
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
"Some days it's just not worth chewing through the restraints"
Are you gonna scrutinize EVERY LITTLE THING I TYPE???? C'mon, stop acting like a bunch of babies for gods sakes. Trust me, I could just as easily follow your posts and find all kinds of faults, so grow up.
I'm not losing sleep because my work doesn't exceed building codes. My work and my methods are fine and long lasting.
Tell me, have you ever had or seen an inspector come out to check on a TILE JOB on a residential remodel? It's unheard of, get real.
If the manufacturer is telling me I don't need a vapor barrier with thier product, how much more do I have to research it before I'm confident about what I'm doing? Do I have to go to the library to look up what the code calls for?
does hardies statement about no vapor barrier being needed, mean that water (liquid water, not vapor) will not go thru hardie backer?
If you spray one side of a sheet of hardie with a water hose 3 times a day (a tough test) will you get water/dampness on the other side of the hardie? Just curious- I am not taking sides in this debate.
Hey Ed, these are all very good questions and I know I learned a few things as a result and I'm sure the other guys have picked up a thing or two (though they won't admit it). You know that saying "you can't teach an old dog new tricks".
The Hardibacker (CBU) that I've been advocating here in this thread is great stuff. Water and vapor will not go thru it at all. The manufacturer has a statement there in the store that tells you a vapor barrier is not required. Their website will also tell you that "vapor pressure" is "not relevant". You (and everyone else) can go there right now and check it out under "technical support" then go to "technical documents" and scroll down to page 8.
I'm not saying that what they're doing is wrong, just saying that it's a waste of time, it's not necessary. Now it might be required for your non-standard installation, like a steam room, and it might be required to meet a warranty. But who wants a lifetime warranty on a product that already last a lifetime?
Other CBU's such as Durock will direct you to your local building codes (mainly to cover their butts). And is Durock IS "vapor permeable". But again, how much of an issue are "vapors" in your basic wet area tile installation?
Think about it, if there was such an issue with "vapors" causing mildew / rot damage to the face of the framing members, wouldn't building codes reflect that by now? Wouldn't they make it mandatory to frame all tub / shower area with some form a pressure treated lumber? It's completely a non-issue with the modern materials and methods we have these days.
Oh, and regarding your question about the corners, again, follow the manufacturers instructions and you'll be fine (embeded fiber tape with thin-set).
Have a nice holiday!
>>Water and vapor will not go thru it at all
Completely false. Who told you this?
Dave, once you install this backerboard (Hardiebacker), water and vapor will not go through it.
"Who told you this"
The manufacturer tells me this. Time tells me this. Sheer common sense tells me this.
Hardie absorbs water right to the other side. It doesn't degrade at all but it will certainly get moist. Do not follow this guy's installation method, it is so wrong and leads to problems down the road.
"Hardie absorbs water right to the other side"
Prove it
"Do not follow this guy's installation method"
I'm simply following the manufacturers guidelines
Do you know how many threads I've read here at Breaktime in which "industry pros? will tell you to follow the manufacturers guidelines / recommendations? Tons
Hey smart guy... stick a piece in a bucket of water and then break it half and try to find a dry spot.If you phone the Hardie rep, they will refer a shower install to their steam room application. The installation you are referring to is a regular wall in a house with no moisture. Before you keep going on about how wonderful a tile setter you are....sorry you are not yet!
"stick a piece in a bucket of water and then break it half and try to find a dry spot"
Whoop-T-Do......Take a piece of half inch backer, hold it vertically and spray it, then get back to me when you see water coming out the other side. Your well will go dry before that happens. Whatever small amount of water / moisture gets past the tile / grout is not going to pass thru the Hardie board.
"If you phone the Hardie rep, they will refer a shower install to their steam room application"
We're not talking about "steam room" applications here, that's irrelevant to this debate.
"The installation you are referring to is a regular wall in a house with no moisture"
Incorrect, the installation I'm refering to is a shower wall that gets a lot of moisture.
Check out this article I found on the FHB website on vapor barriers. Nowhere in the article does the author INSIST on using a vapor barrier, nor does she show one in her diagram. What's funny though is that she does mention that this remains a controversial subject.
Phone the hardie rep and a shower install falls under the steam room instructions....which basically says to follow TCNA guidlines.Moisture does pass through...go phone Hardie and see what they say!
sure...
I got nothing better to do...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
"Some days it's just not worth chewing through the restraints"
You're gonna scrutinize everything I type! Gee...thanks! lol! C'mon, you MUST have something better to do!!
Vapor Barriers are no doubt, a controversial subject. This debate here at Breaktime has been quite interesting. But think about it, if wicking moisture in a shower stall was such a huge issue, wouldn't they have made it code by now to build / frame bathroom shower areas out of pressure treated lumber? That would certainly make sense wouldn't it? You've got all this moisture coming through, and the PT is designed to block / withstand it. Don't you think that the code writers have looked into this at this point? Why would the makers of Hardiebacker tell me I don't need a vapor barrier if there's the chance that moisture / vapors will wick through and cause mold / rot damage to the framing members. Don't you think they've had lab tests prior to making that statement?
take the humor....
it's easier....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
"Some days it's just not worth chewing through the restraints"
I am enjoying a good, healthy debate here. Thanks, guys.If this were politics or Taunton-criticism in the Tav it would be DOA by now. Just sayin'.The Woodshed Tavern Backroom
The Topics Too Hot For Taunton's Breaktime Forum Tavern
Ken, I think this is a good debate also. I've learned quite a bit, I'm not ashamed to admit it, and that makes me the better man (IMO).
I could tell the guys I'm sparring with take great pride in their work as do I and I have no hard feelings towards them.
Each side seems to have a little evidence or something to back them up. I don't think there's one real answer.
Personally, I'm not losing sleep because I'm not stapling tar paper to my studs (anymore) on my tile jobs. Some books will tell you to do so, others won't. Some makers of backerboards will tell you that you don't need a vapor barrier and others will tell you to consult your local codes.
I'll reconsider my methods the day someone pulls apart one of my tile jobs and I see mildew ridden studs rotting away...........I don't think I'll be alive that long!!
Happy holidays!
'Ken, I think this is a good debate also. I've learned quite a bit, I'm not ashamed to admit it, and that makes me the better man (IMO).'Mike-I hope you meant 'a' better man. :o)To me, coming here is ALL about learning. And there is absolutely NO ONE here that I don't learn something from.The Woodshed Tavern Backroom
The Topics Too Hot For Taunton's Breaktime Forum Tavern
I'll reconsider my methods the day someone pulls apart one of my tile jobs and I see mildew ridden studs rotting away<<<I already responded to that line of yours which was along the lines of....it's not just about "rotting"...it's also about mold and breeding grounds for bacteria and like I said before ....I have ripped apart showers that were built with CBU's and no vapor barrier and found mold growing in different areas. Mainly corners and niches.On a similar note....While I use Kerdi b/c it's waterPROOF...I don't just use it because I hope it stops a leak someday but much more b/c I know if keeps moisture from penetrating any cement in my mudpans (or walls) from where the sealer has lost it's effectiveness over time and penetrates the grout to the cement.
Normally the water sits in the cement for a long time before it dries and causes the grout to become dirty looking (moldy). With Kerdi it never gets that far....same with a vapor barrier behind your CBU's.I sleep better at night when I know I did everything in my power to leave my customers with a clean job...meaning not just water tight but bacterior free as well....some of us have children and do actually think about things like that. Others find that a bit fanatical....so call me what you might.
Twenty bucks or less for the felt paper and fifteen minutes of my time for a nice sized shower. Rough work but someone's gotta do it.View Image
The Woodshed Tavern Backroom
The Topics Too Hot For Taunton's Breaktime Forum Tavern
Fair enough.
I'm not going to argue with a guy who's 158 years old!
LOLView Image
The Woodshed Tavern Backroom
The Topics Too Hot For Taunton's Breaktime Forum Tavern
I today emailed the author of the baths and moisture article and asked her opinion on a moisture barrier (tar paper) behind hadrdie backer in a shower.
Edited 7/7/2009 8:22 am ET by edwardh1
I follow codes whenever I'm supposed to. I get paid and I sleep at night.
apparently you don't follow codes, since you don't bother to check because "they're not going to come out and inspect it" ......you're words ....not mine.
Geoff
I told you already, I do know how to lay tile the right way, and my installations will last JUST as long as yours.
So can you post any pictures of your work Mr. troublemaker so I can scrutinize how little you know?
Went to Depot today, a sign hanging on the shelf by the backerboard has a list of "Answer and Questions". Reading down the list, a question reads, "is a vapor barrier needed for wet wall installations", the answer is, " A VAPOR BARRIER IS NOT REQUIRED UNLESS BUILDING CODES CALL FOR IT".
Guess you're not familiar w/ Ct. code.
The cans of mastic that I use say "suitable for wet locations".
It has to be Type 1 mastic to be suitable for wet area use on Hardiebacker
"Guess you're not familiar w/ Ct. code"
Not the parts pertaining to shower installs, but since you are, can you do me a huge favor, and save me a trip to the library, and please recite them for me here verbatum? I'm assuming you either own a code book or just know it off the top of your head so I'll wait to hear back from you, thanks.
"It has to be Type 1 mastic to be suitable for wet area use on Hardiebacker"
I use the Omnigrip that Depot sells. It's suitable for all backerboards and it's Type 1
I left a wet but not water running off it - washcloth on a horizontal piece of hardie, and after about 30 min the water appeared on the reverse side.
A tough test yes
Quarter inch or Half inch piece of backer?
1/2 will be used, but test was on a 1/4 - good point
Mike,Do use the Omnigrip for adhering tile on shower floors?
C'mon, now you're just being flat out ridiculous, I use it for walls only and sometimes on toast.
Anymore dumb questions? I've got plenty of dumb answers. Let's focus on the issue of the debate and not try to nibble at what other things I might possibly be doing wrong. Remember, we're talking about the need to staple tar paper to the studs prior to applying CBU's.
Here, read this article I attached that I found right here at FHB, even the author mentions that VB's are a "controversial" subject. That means that you'll get varying opinions. And the article is written by a woman. Are you argue with a woman??? Her article makes no mention of absolutely having to staple tar paper to the studs.
Now, since every one of you are completely sure that this is a necessary step, why isn't it spelled out or shown by the manufacturer of these CBU's to be a necessary, "do-or-die" step not to be omitted? Are they doing the public a disservice? Are they all supporting poor building methods? Why do they not show that on the labels?
I have books not showing that method, I've seen store displays not showing that method, and manufacturers installation instructions not showing that method. I still feel this is more of an optional step rather than a necessary step. Do I have to do all my installs as if I'm installing a steam room? It just seems a little overkill for your basic install.
However, since the start of this debate, I've certainly been enlightened and can see that for a small amount of money and time, it's cheap insurance. And you all make valid points and I appreciate the passing of your knowledge and methods and of course the occasional ridicule (that's my favorite part!)
I asked a simple question and instead of a simple "yes" or "no" answer you tell me my question is dumb and ridiculous?All I asked was if you use the mastic on shower floors.I was actually trying to help you thorough this, but the heck with it. I'll just offer one bit of advice in a last attempt to help:Learn the applicable building code for the area that you work. It'll help you become a better mechanic and prevent possible liability problems down the road. Do realize that code is the minimum. Meaning it's okay, but there might actually be a "better way" since code, being beholden to political pressures, tends to lag building science by several years.Learn TCNA methods. In general, they are the "better way".
Edited 7/7/2009 12:47 pm ET by Mongo
Sorry, that was my mistake. These posts can read either way depending on the mood one is in at the moment.
Can you blame my defensive behavior after the ridicule I had to endure during this debate?? You'd think I was a serial killer for god's sake....
I'm just going to stop showering or bathing.
5 gallon bucket out in the back yard....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
"Some days it's just not worth chewing through the restraints"
Oh that's funny!
Didn't somebody in this discussion mention that some old methods were better than some new methods?? Maybe that's why some of those old time tiled showers held up so well - they hardly got used!!
Sorry bro but yer dead wrong about not using felt paper behind the CBU's. Sounds like yer just lazy to me. I've been doing tile/reno work over 32 years and I've ripped apart many a shower with cbu's behind it to find studs moldy which breeds germs. The studs may not fall apart but if you're happy with the least bit of a possibility of leaving your customers with even the slightest chance of breeding mold and germs then you're doing them a big disservice. Waste of time you say? All of about 15 minutes of your time if that?
Lots of people I find tilt the shower heads towards the wall so as not to hit the shower curtain or door and when they're not doing that a lot of people take long hot steamy showers that penetrate anything thats penetrate-able.
Call me overkill in your book maybe but in all that I do I try and do it the best way I know how.
My favorite choice of all choices is Kerdi over cbu's,,
Each to their own I reckon. http://www.cliffordrenovations.comhttp://www.ramdass.org
Edited 7/2/2009 9:43 pm ET by andybuildz
Mike, Are you also the guy who keeps building shower pans with the membrane flat on the subfloor?C'mon, if you want to build sub-par construction, have at it. But don't ridicule others for detailing tub surrounds the proper way.
I apologize for any ridicule, of course I've only recieved it here at the forum, this was the first time I dished it out.
I'm definitely not one for "sub-par" construction and stand behind all my work.
I just typed a post with a valid explanation of why it's waste of time (in my opinion) to staple tar paper to the studs.
In case you haven't noticed, we have different and better building materials these days compared to days of old. These new products work with us as installers and home owners to achieve a better, longer lasting job.
Remember when old bath tubs didn't have that nice drainage flange that new bathtubs now have? That added flange now eliminates the hazard of "pooling" water.
Remember when greenboard was the material of choice for shower locations? Well now they have cement board. Again, they've created better building materials thus making life a little easier for the installer.
Mike, You sound like a stand-up guy who takes pride in his work. That's good.As far as "new technology" versus old, I've been using Kerdi for the past 13 years or so. So I'm pretty much up to date on new technologies versus old.I noticed you're in CT, I sit on a couple of arbitration boards in central and southeastern CT. When the #### hits the fan and someone's house starts rotting away, my phone rings. The number one cause of failure in shower assemblies is the membrane being installed flat on the subfloor. The membrane is flat with the slope on top of the membrane. The number two cause is no vapor barrier behind the cement backer board and the framing.The number three cause is mastic used to adhere tiles in showers and tub surrounds.Some mastics are approved for use in "intermittently wet areas" as defined by ANSI. But even then it's #### shoot. I've seen mastic re-emulsify behind the tile and ooze out the joint between the tiled wall and the tub. Mastic can not be used on a shower floor. Ever.Mastic cannot be used in a steam shower. Ever.In older houses, or in new houses that have not so tight thermal envelopes, air infiltration through the house can be high enough where a little moisture that gets into the walls might not cause big problems. The air infiltration through the envelope is significant enough to allow for adequate drying cycles. In tight house, not having a vapor barrier behind a shower wall could be a bad thing. That wall could be the weak link in the envelope, and when the house becomes pressurized, significant moisture could be driven through the wall and into the framing bay. Pressurization cycles typically occur in the heating months, and moisture driven into the bay could easy reach dew point and condense out.Realize that this talk about "moisture" doesn't necessarily mean "liquid water". Most of it is moisture vapor. It was shocking to me how much moisture can be driven through a tiled and grouted wall assembly.Trust me, I'm not picking on you or ridiculing you. I'm just trying to make the world a better place, one bathroom at a time.<g>
I'm in Waterbury (unfortunately) but most of my work is in the high dollar towns, Greenwich, Wilton, Darien, etc... So as you could imagine, my work has to be spot on.
If you're telling me you've seen court cases involving VB and mastic, then I believe you, but not one tile job I've done gets inspected. There's just no need to waste a trip to the local library of whatever town I'm working in to find out whether or not a VB is required for my tile job in that town, there's just no need.
If the manufacturer tells me a VB is not required then that's all I need in my defense should I go to court. "Your honor, the can says: suitable for wet locations under ceramic tile". That's all I need to know. I sleep at night and nobody is calling me complaining about my tile jobs.
I like the lesson on "thermal envelopes" and "air filtration". I find it fascinating and I'm always eager to learn something new.
We should meet for coffee!
"In case you haven't noticed, we have different and better building materials these days compared to days of old. These new products work with us as installers and home owners to achieve a better, longer lasting job."
Not all new materials, or methods, are better, EIFS comes to mind, in fact some old methods are better than some of the new methods.
"Remember when old bath tubs didn't have that nice drainage flange that new bathtubs now have? That added flange now eliminates the hazard of "pooling" water."
I don't know how long you've been doing this, but I've pulled tubs from the 30's that had a flange.
Remember when greenboard was the material of choice for shower locations? Well now they have cement board. Again, they've created better building materials thus making life a little easier for the installer.
Neither material is water proof, greenboard fell apart, along with the mastic (due to moisture penetration); CBU's allow water to penetrate to the framing even though the tiles may remain attached to the backer (w/out a VB), and they require a VB behind them to meet warraty requirements! Now there is Kerdi or Densshield(and others) both of which are waterproof, and Densshield has been around for nearly 20 years!! Kerdi has been around for at least 15 years!!
If you feel there is no need to use a VB behind the backer then use a waterproof backer, problem solved. Densshield is much easier to work with than CBU's anyway.
Geoff
Edited 7/3/2009 4:09 pm ET by Geoffrey
" and they require a VB behind them to meet warraty requirements"
No they don't Mr. Smarty pants, went to Depot and saw it with my own two eyes this morning.
Hardibacker (has in writing)- DOES NOT REQUIRE A VAPOR BARRIER. I'll be posting a picture of that Monday.
Durok offers a lifetime warranty, makes zero mention of having to use a vapor barrer.
(by the way, at this point, I'm LOVING this discussion because I know I'm right!!)
"And when's the last time you opened up the wall behind the tile to see if there is any water damage/intrusion?"
Good question. A few weeks back I had a to replace a shower faucet in a tiled tub I installed about 5 years ago. I had to replace the faucet from the backside, through the closet. I opened up the sheetrock, and guess what? DRY AS A BONE.
And wouldn't you agree that water splashes off your body and it hits the faucet wall? I would. So there, no water, no condensation, no need to have wasted time stapling tar paper.
"Look at the photo "Hackinatit" posted"
I did, and the photo doesn't show or explain what was on the walls beforehand, so we're not getting the whole story here. Was it greenboard or was it a CBU?
I've recently done a remodel on a tub surround with a poly vapor barrier and spent an extra day and a half on rot repair and remediation. It traps moisture! Especially on exterior walls due to temperature and humidity differences.
Tile will be fine grouted and sealed. put the backer directly on studs, butt to the flange, thinset and fiberglass mesh your seams//corners.
You can fill the gap with a little thinset while you're at it if you'd like.
My theory on caulking tub/wall:
Tile set vertically, properly grouted and sealed sheds water. Any water that actually soaks into the tile/grout itself will travel downward. Placing a "waterproof" bead of caulk like silicone creates a little dam not allowing the water(what little there is) in the actual tile to leak down the legs. Or if the tub isn't set right, holds water in the low spot creating a higher potential for rot damage from the wicking effect into the backer and eventually studs.
You can also use a product called WEDI which is a foam centered concrete backer board. It cuts with a utility knife and is waterproof on the surface.
Tu stultus es
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Look, just send me to my drawer. This whole talking-to-you thing is like double punishment.
Ed, my installation methods are perfectly fine since I follow the manufacturers guidlines.
You will not have problems down the road (disregard "Westcoats" last comment)
backerboard does seem to wick water- i put a piece in a pan in the kitchen and it wicks up on both sides.
I also have a 1 ft square piece with a wet washcloth on it trying to see if it comes out the other side.I know its used a lot (hardie) and I like hardie stuff bit the wicking botehrs me - like does it wick up from where the backerboard overlaps a tile flange on a tub?
>>backerboard does seem to wick water
You don't say....
>>like does it wick up from where the backerboard overlaps a tile flange on a tub?
Yes
Ed,
If you're concerned about moisture you can use Densshield instead of Hardie as a backer. It is not a CBU, but comes with a waterproof face which is also dimpled/textured to help wth adhesion. Densshield is also easier to work with, very similiar to drywall, it's also available in 4'x8' sheets so you can stand 1 sheet on each end of the tub/shower and run it horizontal on the long wall, the cutoffs from the two ends are usually enough to finish to the ceiling on the long wall.
This means you have no seams on the "wet" wall and the rear wall, and the seam(s) on the long wall are about a foot higher than with 3'x5' board. The board can be hung using 1 1/4" gal. drywall screws then covered with a spot of caulk and caulked at the inside corners and along the flat seams, thus giving a waterproof surface to apply tile to. Also, Densshield will not wick water, or turn to mush if it does get wet.
Geoff
" i put a piece in a pan in the kitchen and it wicks up on both sides"
That's an unfair test. The Hardie backer is not made of plastic / fiberglass. It does have wicking properties. This I knew. But when it's installed in a shower with tile over it, whatever itty bitty amount of water / moisture that might find it's way there is no way in hell going to make it to the backside of the piece.
"I know its used a lot (hardie)"
It sure is
"but the wicking bothers me"
It doesn't bother me or the hundreds of other people out there who use it.
"like does it wick up from where the backerboard overlaps a tile flange on a tub?"
No because that gap is caulked with silicone, and if it worries you still, just install the backer a little higher so it's not touching the tub.