"Tony" wrote in message
...
On Thu, 09 Aug 2007 11:42:36 -0700, RickH
wrote:

On Aug 9, 12:36 pm, Tony wrote:
On Thu, 09 Aug 2007 10:17:24 -0700, RickH
wrote:
On Aug 9, 12:00 pm, Tony wrote:
I am about to tile my 5x8 bathroom floor. I am using Hardibacker
board. Right now, I have a plywood
floor that I am going to thinset and screw the hardibacker to. I laid
a 4' level across the floor.
In the middle of the floor (horizontally), if I press the level down
on the right side of the 5'
wide floor), the left side is up at least 1/4" and almost 1/2" at one
point. While I have no real
problem if the floor is slightly off level on the whole, I do not
like this small buldge that seems
to be in the middle of the floor. I tool a smaller 1' level and laid
it all over the floor and it
slightly rocks back and forth. If the level does this, the tile will
do this too.

Will the thinset under the hardibacker board level this out? What is
the best way to level this
floor?

Tony

Screed it all the way across with some dryly mixed mud bedding and a
long sturdy aluminum straight edge (a piece of aluminum angle stock or
something cut to room width). So that the mud brings the low spots up
to the bulge peak (peak itself does not need to be buried). If you
can screed the full width of the room at one pass it will be perfect.
Let that dry. Now thinset the floor tile as you normally would. You
may need to screed both directions the 5 foot and the 8 foot depending
on how the peaks run, toilet flange in the way, etc.

Thanks for the reply Rick. I am a tad confused. I had 18" tiles I was
going to lay down diagonally
until I talked to my friend yesterday, who is a builder. He told me that
there is no way I can use
18" tiles over hardibacker boad and that I neeed to mud the floor. Most
guys around here charge
about $350 to mud the floor, plus it may not be until a few days that
they can do it. I need this
done NOW. So, I returned all of the 18" tile and bought 12" tile and was
going to start today. Then,
I checked the floor and notice a tiny slight buldge in the middle.

So, is what you described above considered "mudding" the floor? Is mud
the same as the thinset that
hardibacker recommends we use between the subfloor and the board? I have
dur-a-flex thinset.

Tony

I wasnt going to "mud" the bathroom because most guys- Hide quoted
text -

- Show quoted text -

The store should know what you need, it's called mortar mix, basically
a sand mix, trick is not to mix it too wet when using it to screed
level. It's sold mostly for brick laying but I've used it to make a
mortar bed and do leveling just like you described. Your thinset is
basically portland without sand and is NOT made for leveling a floor,
just sticking tile. Just dont mix the mortar too wet, a handful
should stick into a ball but not be a real sloppy kind of wet almost
just damp (with no dry powder pockets of course). The 12 inch tiles
should do fine, he was right about the 18 inch you could easily crack
a tile like that over just plywood. Good idea to transport any tiles
on edge too not laying flat until you are installing them, and never
step on any tile till its setting is under it.

So, if I do the morter mix as you suggested, can I use 18" tile safely
over it? I was never going
to put it on the plywood. I was going to put it on top of the hardibacker
board until my friend said
it still wouldnt be sturdy enough to hold it without the tile cracking
eventually.

I am confused about the screed process you mentioned. How do I know if the
screed is level. In other
words, what is to stop me from holding it on a slant, preventing me from
getting a true level
surface? What if I holding it higher on one end than the other as I screed
it from one end to the
other?

there's level, and then there's flat. you only need flat to tile on, it
doesn't have to be level, although it's nice if it is.

you prevent unlevel-ness by attaching boards to both sides of the room and
having a long enough straight edge that it spans the width and rides on the
boards.

it's nbd if it's a little off level. it is a bd if it is off being flat.

Also, is this what everyone refers to as Mudding?

no. mudding is laying down a thick bed of mortar and using that as a base
instead of plywood and hardibacker.


Tony