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Don't shoot me, just a ?

11K views 34 replies 13 participants last post by  ccoffer  
#1 ·
Does anyone use 1/4" Luan for underlayment, under ceramic tile, in a kitchen/entry are? I know about the tile-backer, hardie, etc.
That is all we used YEARS back, just wondering if any still did it, or what?
Just a thought, had a tear out today, with Luan underlayment, what a pain in the butt!!!
 
#3 ·
Multiply or integraply, but not luan. Staple it off with narrow crown staples every 4-6", closer at the joints.

I wouldn't use it under ceramic tile, but never had a problem with it under vinyl and vinyl tile.
 
#6 ·
We just tore out 450 sq feet of ceramic on top of 3/8 ply (not luan) underlayment on an 80's house this week. You could practically shovel it right into buckets it came up so easy:thumbup:. The 3/8 ply was glued with yellow glue and stapled to the 3/4" OSB subfloor underneath. That was a bear to get apart :mad:. I haven't seen anyone tile on ply in 8-9 years at least.
 
#17 ·
Not sure how long the tile "job" lasted. The tile itself lasted 25 years sitting on top of the plywood with gravity holding them down. Quite a few of them weren't adhered to the substrate for the full 25 years.

I don't know at what point a lot of them came loose and cracked but there was hardly any thinset stuck to the plywood, it all came off with the tile. My helper used a 3' crowbar and just pushed it up and down the rows of tile popping them up like shoveling snow.

I'm sure there are plenty of long lasting tile jobs over plywood but this wasn't one of them.
 
#8 ·
Does anyone use 1/4" Luan for underlayment, under ceramic tile, in a kitchen/entry are? I know about the tile-backer, hardie, etc.
That is all we used YEARS back, just wondering if any still did it, or what?
Just a thought, had a tear out today, with Luan underlayment, what a pain in the butt!!!
I'm sure they do.... then leave town.
 
#14 ·
Yes. Laticrete is actually quite robust in their advocacy for going over plywood instead of backer board. The reason is plywood adds rigidity to the assembly whereas CBU does not. Keep in mind, they want you to buy their 30 dollar a bag stuff to do this. Also, Laticrete doesn't make CBU. :)

Personally, I think it's a bad idea. Even the best thinset is going to lose plasticity over time. Even the best plywood panel is going to expand and contract at a level wildly different than ceramic tile. It seems a fool's gambit in the long run.

Maybe I'm wrong.
 
#15 ·
Hey Dave,

I have never used it under ceramic. But I'll tell ya what, I have torn up a bunch of it with ceramic over it doing kitchens and bathrooms. A lot of the floors were still in great shape with no movement or cracking and weren't the easiest things to get up.

I remember one in particular in a kitchen. They glued the luan with wood glue to the plywood subfloor. It took a lot of time to get that mess up!:laughing:


Dave
 
#16 ·
Better check your luan for actual type1 performance. The only 1/4" underlayment around here that claims to be type1 isn't luan, and it's way expensive

All the luan around here is 5mm and even if it's sold as underlayment, it will delaminate of it gets wets.

Less than 10 years ago you could get luan with good glue - I'm not finding any any more.
 
#31 ·
Using a plywood that is manufactered for ceramic installations isn't a problem. Luan has oils that prevents thinset from adhering properly. No thinset manufactures allow luan substrates.

The premium thinsets will stick like crazy to plywood. Kerabond/keralastic or 254 Laticrete work well with the proper plywood. They are also more flexible .

Also, I think stapling the plywood versus screwing it , allows minute expansion/contraction .

Done correctly, plywood will last as long as cement board. Plywood can add strutural support that cement board can't.