Tile experts ???

[derailed]

I have a question for any tile contractors that may be here? I am redoing my entire bathroom which has a standup shower in it. My question is do you prefer to mortar the backer board to the sub floor or just screw it down every 6 inches or so? The last 2 jobs I did on my kitchen and other bathroom I just screwed the cement board to the subflooring and then laid porcelain tile over it (5 years now with no problems). The reason im asking is it seems half the guys I talk to do it one way and half do it the other and im wondering if theres any real reason to mortar it if its screwed down. Is it a moisture issue? Also has anyone here made a mud base for a shower or used the new shluter/kerty system?

[NHCharger]

it seems half the guys I talk to do it one way and half do it the other

yeah, that sounds about right.
I'm a general contractor, not a tile guy, but my tile guys always screw down the backer board.  I screwed down my backer board when I built my house in 99. No problems with the tiles.
As you mentioned you haven't had any problem with the way your doing it, why switch .

[derailed]

.
As you mentioned you haven't had any problem with the way your doing it, why switch .

Good question. I guess I am just curious why these guys are so insistant on the issue of mortar or no mortar and if there is a good reason for it. The big thing im worried about is moisture getting trapped somewhere. My house was built in 69 and they used no backerboard or waterproofing of any sort behind the tile on the walls. The sheetrock was badly rotted behind the tile and when I gutted the room it stunk of mold something fierce and we all got sinus infections. The studs are all still solid and so is the subfloor but I want to get this stuff down to get rid of this stink. For what it costs I think I will put some mortar down first. Im going to use the schluter system for my base.

[moparnut]

What we usually do ,liquid nail the cement board and use roof nails,Or mortar bed and roof nails for the cement board.Screws have a tendancy to break out the area they are in and dont hold verywell.Another thing is we use a fiberglass mesh tape on all the cement board seems.After being called back a few times for cracking,the mesh tape has worked well. moparnut

[Orange_Crush]

It depends how much square footage and what type of subfloor you have.

Anything over 100 square feet I always go with mortar and screws and 1/2 inch cement board. In a bathroom, I always take it down to the joists and put down a new subfloor of 3/4 inch treated ply with 1/16 inch spacing between sheets for expansion room.  Then I use a thin-set mortar to put down the cement boars and screw it down with deck screws. 

I always build a mudbed for the shower.

[dkn1997]

I just did my bathroom.  I used construction adhesive (PL) and screwed the crap out of it.  I did not use the usual cement board or greenboard.  this stuff was gray, really heavy, 1/2" thik, and I could cut it with a utility knife (very hard to do though)  It was not as hard as cement board I used in the past (you could not screw that stuff because it was so hard the screw head would not dig in and si above the surface)

[derailed]

The room is pretty small. The subflooring thats in there now is in good shape other than the odor. The old tile that was in the floor had some kind of backer with chicken wire in it and almost looked like potting soil below that when I broke it up. Im going to go over it with wonderboard which I think is what DKN is talking about. Its a little bit easier to work with than the Durrock ive used in the past. I will post some progress pics when I get a chance. I found this sight with alot of good info on it when I was doing some research in case anyone else has some projects going on.

http://johnbridge.com/vbulletin/index.php?

[dkn1997]

it was wonderboard.  really nice because the side that is "up" has a pattern molded into it. give the mastic something extra to grab onto.  takes a screw really nice.

[derailed]

it was wonderboard.  really nice because the side that is "up" has a pattern molded into it. give the mastic something extra to grab onto.  takes a screw really nice.

The pattern also works good for doing measurements in 1" increments and helps if your score/snapping. I got it all liad down tonight and im going to hang the half inch on the walls where the shower will be hopefully tomorow.