[MisterSteve]

I have pulled up the old linoleum in my bathroom and found lauan as the underlayment. After doing some research it seems unanimous that the lauan be removed for a ceramic install and I plan to do so. I hope its not glued... My subfloor is 3/4 OSB. Will I need an underlayment between the OSB and 1/4" cement board. What are my options? Joists are 2x10 16" oc 13' spans. Deflection is about L/458.

 

[JazMan]

Hi MisterSteve,

Your 3/4" t&g OSB installed correctly and in good condition meets all minimum standards as a subfloor for ceramic tiles. Your joists are probably fine too as you said, but do you know their species and grade? L458 from JB's place is based on Douglas Fir or Southern Yellow Pine grade #2. Is the span 13' 0" or a few inches less?

You're probably OK, but you should double check. Be sure to install all CBU's into fresh thinset mortar, fasten and tape all joints.

Jaz

 

[MisterSteve]

Lauan removal is wearing me out... Of course it was stapled about 14,000 times and liquid nailed. WHY??? Any suggestions as to how to get this off would be much appreciated. Just been plucking staples with an arsenal of bars and pliers but getting the glued areas up is painstakingly slow with just a small scraper. And anyways, how smooth does it really need to be before laying the backer board? THANKS

 

[JazMan]

When I rip out luaun and vinyl in a good sized area, it usually takes me a couple of hours to get them out and the rest of the day to hammer down the remaining staples.

They should have shot a staple every 2-3" on the perimeter and 4" in the field. If I remember correctly about 275-300 per 4x8 sheet.

Of course it was stapled about 14,000 times and liquid nailed. WHY???

Because the person who did it didn't know any better. :yes:

I've run into that myself. One time the luaun was glued about 90%. Wasted a day and HO worked all evening to remove 150 ft. Another time the staples were literally touching each other at the edges. I'd remove 8-10 within the size of a quarter.

The floor needs to be very smooth and flat.

Jaz

 

[MisterSteve]

Ok so the floor joists have stamped "SPIB KD19 NO.1" on them and the distance between each end or span is 12'8". The subfloor is 3/4" Advantech.

When removing the glued down bits off lauan, it will sometimes pull up about a 1/8" deep chunk of the subfloor. Is filling these voids with thinset adequate or do I need to fill these voids with something else? The staples were about every 3"-4" and 8" oc. The staples are not so bad to get up but I would not wish removing the liquid nail chunks on my worst enemy... Seems totally unnecessary to have glued the lauan down.

 

[JazMan]

Not only is glueing the underlayment unnecessary, it's not recommended. The beads of adhesive make small humps which causes voids under the plywood and therefore deflection.

I think your joists meet minimum specs at 15' 1". You should be just fine if installed correctly and in good shape. That floor should feel pretty solid. I wouldn't worry about small shallow missing chunks. The thinset in the next step will fill the voids.

Jaz

 

[MisterSteve]

Jazman, thank you for your help by the way. All of the lauan is up and backerboard down. Now, after laying the tiles out, I could really use some tips on where to start. It seems like grout lines are often centered at the base of the toilet. Is this just because it's easier to cut the corners of four tiles to fit around the flange? This layout works fairly well but I would end up with about 2-3" pieces along the back wall. It's possible to get nearly full tiles all the way around each wall but my cuts would be a little tricky around the toilet. Layout tips are much appreciated, thanks again.

 

[JazMan]

I don't let the cuts around the toilet influence layout. Post a floor layout with measurements. There's a way to cut them regardless of how it works out.
a tile can even be cut into two with the cut covered the the toilet.

Essentially you want whole or large tiles at the doorway and the main wall and nothing less than half a tile where they are visible. There can be exceptions.

Jaz

 

[MisterSteve]

Jazman, I went ahead and laid the tile in a brick pattern with 16 x 16s while keeping as large as possible tiles at the main wall and entry. My wife is not fond of how light the grout is and it does make it look a little "busy" against a dark tile. I'm reserving my full judgement until it is all completely finished. Is there even a way to stain or darken the grout? Also, there are some areas that have smudges or hazyness to them. For example there is an outline of a bucket that is clear as day on one tile. I have read about people using a light mixture of vinegar and water to clean these spots. What would you reccommend? Another thing I did not consider was the height of the toilet flange, it now sits about a 1/4" or so below the tile. The toilet did not have a wax ring on it which seemed odd to me. How high do I bring the flange up? Do I use a wax ring or extender or both? THANKS!

 

[JazMan]

Grout stain to change the color of grout and seal it permanently. As long as it's cementitious grout and not sealed. Try white vinegar to remove the haze. Start with a mild solution. They make products for this too.

Ideally the bottom of the flange should be at the finished floor level. It's not a problem if it's lower or a bit higher. Use extenders to raise or an extra thick wax ring or even two stacked on each other and longer bolts.

Jaz

 

[MisterSteve]

Jaz, This is what I'm working with here. I guess it's called a wax free seal. Is it presumably still good to use again? It seems firmly attached to the toilet and plenty long to sit inside the flange hole.

 

[JazMan]

OK, that's a Fernco gismo and I've never used one of those. Fernco products were invented in a city near me. Ferndale, hence the name Fernco.

Looks like they self adjust as it's set. Is that lower collar still free, can it be pushed down so it'll side up to seal?

Jaz

 

[MisterSteve]

Jaz, I went ahead and sat the toilet in place. The waxless seal had a about an 1 3/4" inside the flange and I think should be fine. Of course I'm not a plumber though... I'm curious what your take is on expansion joints. I'll be putting down wood flooring and it ALWAYS calls for an expansion gap at the edges, yet I see wood butt right up against tile all the time. I have already decided to go with transitions where tile and wood will meet but I'm curious. Also, if I wanted to get creative with my kitchen tile and put something in the center, would I then start from there. I know thats probably too vague...

Thanks again for all your help, it is much appreciated.