# screws that wont rust !!



## gma2rjc (Nov 21, 2008)

When I bought Durock, the screws that are meant to be used with it were located within a few feet of the stack of Durock. They're called Buildex Rock-On and they come in 1 1/4" (200/box) and 1 5/8" (150/box).

I don't remember if I had to counter sink them or not, but I'm pretty sure I did. I guess you wouldn't want the screw heads sticking out above the surface of the Durock.


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## Bob Mariani (Dec 1, 2008)

The CBU screws are flat head and will set flush with the board. But... you need to coat the entire surface, seams nails, everything with Redgard waterpoofing. Tile and grout even sealed will still let moisture into the wall. Keep the bottom board off the floor enough to prevent wicking water up the bottom edge. SOooo. no special rust poof screws are needed.


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## gma2rjc (Nov 21, 2008)

I'd still go with the rust-proof screws recommended by the Durock manufacturer. No matter how well you seal things, there is still a potential for water to get in.


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## determined1 (Feb 27, 2009)

Thanks for your help. The redguard I already planned on doing ,but I don't understand about not letting the durock touch the shower floor. The drywall in the shower now doesn't go all the way down and the water managed to get behind the bottom tiles, loosen them, and the greenboard disolved. I thought I was supposed to have the durock go all the way to the bottom, butt up against the tile floor and just make sure I seal the heck out of it.


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## Ron6519 (Mar 28, 2007)

Keep the cement board off the floor by at least 1/4".
Ron


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## Matthew in TO (Feb 2, 2009)

gma2rjc said:


> They're called Buildex Rock-On


There's also Backer-On for Hardibacker board. Here's the site here in Canada... http://www.buildex.ca/product/31/rock-on-backer-on-fasteners-cement-board-applications


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## joecaption (Nov 30, 2011)

You need room for the caulking at the bottom of the walls, that's why you leave a space. Thin set should not be used in the inside corners or any place the tile touches a differant surface, or changes direction.


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