Flooring Tile - Permabase cement board???

What do I need to use with permabase cement board to waterproof the wall? The guys at Lowe's were telling me that permabase will let water through, but all I need to do is seal the grout, but I am not too comfortable with that, since one wall is an exterior with insulation and another has a tv cable running through it. I saw in John Bridge forums someone using black roof felt behind their hardibacker. I am also building a couple of niches, and would like to know the steps as far as waterproofing those. I am just wondering if I should take the permabase back and get hardibacker. I keep hearing people say "a matter of personal preference" but I have no experience with this stuff, so I don't have a preference! Any help would be greatly appreciated.

OK, so I'll reply to myself :) I found the answer, if anyone else might be interested.... Found that 15# roofing felt behind the permabase is sufficient vapor barrier. Around niches would need redguard, but that is already covered in a post here lately.

Thanks for the ansewer. It was YOUR turn to answer LOL. Good luck.

You're right, I guess it was time for me to say something instead of asking :) Here's something else I learned:
1. More than likely, the guys at Lowe's or Home Depot know as little as or less than you do about any given project :rolleyes:
2. You truly can find out how to do anything on the internet.
3. You can do a lot more than you ever thought you could if you take it one step at a time.
4. Plumbers earn every cent they make... (refer to the plumbing thread for more on THAT..lol)
5. I may be stuck with man hands for the next month or until I get this bathroom done :p
6. Making lists is fun
7. I just might really need to get a life....

If making lists is fun #7 may be true. :)

amen, brutha! OK, so I actually have a life, he's just in Iraq right now :)

Did you get your information on the niches?

Real quick for you, frame out the opening(s) you want and where you want them on the walls with 2x4s. Make the rough opening about 2" taller and wider than what you want the finished opening to be.
Cut a piece of cement board (Hardi, Permabase, Wonderboard, DuRock, etc, etc) the size of the opening and use liquid nails or construction adhesive glue to hold it to the existing wall on the backside of the wall studs.
Cut 4 more strips to wrap around the studs framing the niche opening. Push them tight to the piece glued to the back wall and cut them flush to the edge of the studs. On the bottom one, glue a wooden paint stirring stick to the rear of the flat 2x4 before you put the cement board strip in place to give a little pitch so the water runs out. Put up the roofing felt or 4 mil thick plastic drop cloth (either will work fine). Hang the rest of the cement board. Tape the seams of the cement board and the corners in the niche with mesh tape and cover with a thin smooth coat of modified thinset.
After the thinset dries,paint the back wall and side strips of the niche with the waterproofing membrane (like Redgard), put on two or three coats and really work it into the corners and overlap the outside edges of the niche.
The niche is now waterproofed and pitched on the base and ready for tile.

And most important, please send my thanks to the TRUE AMERICAN HERO serving in Iraq. :)

Thanks Tileguybob! That is exactly what I needed to know! I was making way too much work for myself going at it on my own. Very simple and easy to follow instructions, and great idea about the paint stir. I can't wait to get this thing tiled!
I will definately send along your thoughts to Aaron. It is so nice hearing from people who appreciate his sacrifices (even though he did get out of remodeling the bathroom by going..lol). Maybe I'll make him a list of nice things people say about him...lol. Okay, I'll stop....

I'll be offline for a week but if you have any more ??? just post them and others who check in often (can you hear me Daniel and TileBri) will help you along.