Drywalling question (drywall over drywall) and self leveling backerboard

icyclefar

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and as a side note ............ I learned a long time ago never bother trying to strip tile from it's substrate. It's pointless be it floor or wall, the surface you're left with after removal is junk and requires so much added prep work that its just not worth it. Take it all out, and start fresh.
 

PaulR

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Remember, "code" merely establishes the minimum acceptable methods to get an approval.

I seldom build "to code".
Yes and no, code can mean a lot of things. We had to make $38,000 worth of renovations to our building for a handicap access ramp that has been used 4 times in the past 5 years. Code can be annoying as hell.
 

ToddDubya

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Unless you're a competent sheetrocker you might consider hiring that part out. I can't stand when I can see poorly taped seams.
 

icyclefar

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Yes and no, code can mean a lot of things. We had to make $38,000 worth of renovations to our building for a handicap access ramp that has been used 4 times in the past 5 years. Code can be annoying as hell.
Look on the bright side, you could have chosen to add an elevator!
 
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and as a side note ............ I learned a long time ago never bother trying to strip tile from it's substrate. It's pointless be it floor or wall, the surface you're left with after removal is junk and requires so much added prep work that its just not worth it. Take it all out, and start fresh.
All areas to be retiled have been stripped beyond. I've pulled up the old backer, the linoleum that was under it, and the tile from the floor. The walls will not be tiled, just the shower surround at the top which is all new.

I just see no reason to rip that last wall down. I mean, I guess I could, I already ripped down 2, but my googling seems to suggest there is zero reason not to drywall over existing drywall. No downside whatsoever if the wall is solid/flat/etc. So why would I bother? The protrusion into the room will maybe be a quarter inch more than it was when the walls were tiled. Upstairs will all be to the studs cause the walls are all ****ed, uneven, etc.

On the note about bad seams... The bathroom is small, so I think I'll have like 1 or 2 seams mainly covered by the toilet and vanity. If I'm not happy with how it comes out we have a family friend who does excellent finish work and I'll have him come in and fix it. Based off youtube it seems like for this size project it shouldn't be too hard.

Does anyone have any experience with self-leveling backer board for flooring?

Mike
 

JJ4

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If you have the floor up, put down electric radiant heating. Suntouch mat was easy to do. Buy from ebay. Best thing ever in a bathroom to have warm floor tiles.
 
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If you have the floor up, put down electric radiant heating. Suntouch mat was easy to do. Buy from ebay. Best thing ever in a bathroom to have warm floor tiles.
I've thought about it. I think more than likely when we redo the boiler I'm going to have a hot water zone and pex under the kitchen and bathroom floor joists. Having an unfinished basement has its benefits. Wicked easy access to everything. We aren't remodeling our kitchen per se, just getting new cabinets and changing the way the cabinets are layed out, but that does involve removing a steam heater, which with uninsulated walls may require the radiant heating.

Mike
 

je25ff

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Good idea to strip it to the studs. If it's an outside wall, the mice like to carry off the insulation. Ask me how I know. Jack.
I can never tell if you're signing off with your name, 'jack' or if you're using some sort of colloquial sign off like that old guy from Duck Dynasty.
 
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Does anyone have any experience with self-leveling backer board for flooring?

Mike
Yes. Self leveling cement. Mix it well with a heavy drill and make it viscous enough that it will pour and spread on its own. Clean and prime the subfloor to help adhesion. I used tape at the edges to ensure it doesn't run into voids at the walls. They're proud of the stuff and I think for good reason.

A friend would always pour bathroom floors in rentals to help prevent water damage from overflows etc.
 
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Yes. Self leveling cement. Mix it well with a heavy drill and make it viscous enough that it will pour and spread on its own. Clean and prime the subfloor to help adhesion. I used tape at the edges to ensure it doesn't run into voids at the walls. They're proud of the stuff and I think for good reason.

A friend would always pour bathroom floors in rentals to help prevent water damage from overflows etc.
Thanks

I was doing research on backing the floor tiles and this stuff seemed to keep popping up and seemed brilliant. I guess I'll go that route. I'll just stick some plumbers putty around the closet flange and silicon where the drywall meets the subfloor, etc.

Do you know if I need to leave an expansion gap like is recommended with the tile?

Mike
 

icyclefar

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Keep in mind that pour in floor leveler is not a suitable subfloor for tile. That is not to say you can not put tile on it, you can, but it is not structural so you need to make certain that you still have an adequate subfloor below.

Mud set concrete board (wonder board, hardy board, etc) is typically the way to go.
 
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I was under the impression tgat the henry levelpro 555 was a substitute for backer board.

Mike

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icyclefar

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I was under the impression tgat the henry levelpro 555 was a substitute for backer board.

Mike

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Nope

It offers no structural value, it is just a leveling compound.

It's own instructions specify a minimum underlayment of 3/4" tongue and groove plywood, however while good enough to level off of, I would still not put ceramic over that.

Mud set backer board over a minimum of 1/2" plywood is the way to go.
 

icyclefar

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If you have a strong deck (5/8" plywood or better) you can get away with 1/4" set in thinset. it will end up laying up to almost 1/2" with the thinset under it.

Screw down the deck before you begin and screw the backer board too. Make sure you tape and mud the seams.

I always cut and lay all the backer dry, mark the pcs then pull them all out, mix the thin set, then lay it all back in.
 

Fixxah

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If the house is old and has recessed medicine cabinets, beware of the inevitable pile of razor blades in the wall directly below the slot in the bottom of said cabinet.
 
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So despite following the directionsthe self leveling compound poured a little clumpy in some spots and did not perfectly level the floor, but its pretty close. Since I'm putting 1/2" cement board over it should I be overly concerned? I figure if I knock the few clumps off the top the slight imperfections should be made up by the thinset, no? Its a helluva lot better than it was? But not as perfect as I was hoping it would be.

Mike

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Skysoldier

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If the house is old and has recessed medicine cabinets, beware of the inevitable pile of razor blades in the wall directly below the slot in the bottom of said cabinet.
I once owned a three story, Victorian in Indiana when I was going in college. I used the upstairs medicine cabinet as a piggy bank. When I sold the house, I had to
go to the first floor and remove the baseboard. Hundreds of razor blades, an over a grand in quarters![smile]
 

calsdad

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So despite following the directionsthe self leveling compound poured a little clumpy in some spots and did not perfectly level the floor, but its pretty close. Since I'm putting 1/2" cement board over it should I be overly concerned? I figure if I knock the few clumps off the top the slight imperfections should be made up by the thinset, no? Its a helluva lot better than it was? But not as perfect as I was hoping it would be.

Mike

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I would be. Cement board isn't really a "structural" product. If there's high spots on the underlayment - and you put the cement board over it - you're creating pressure points on the cement board that may eventually lead to cracks.

Knocking the humps off and putting down thinset or something that "beds" the cement board evenly is a good idea IMHO.
 
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Ok. So I'll put a thinset bed down first, and lay the backerboard over that. I thought about trying another layer of self leveler but I dont have the space. Its a small 36 square foot bathroom.

Mike

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Thinset and 1/2" backer and some help from a buddy and its all in and level.

In hindsight I probably used the wrong kind of mixer for the levelquick. I bought a paddle mixer for the thinset and it worked awesome. I used a screw type mixer for joint compound on the levelquick and I guess it just didnt do the trick.

My milwaukee fuel brushless impact driver might be the best tool Ive ever bought as far as driving and removing screws goes.

As far as contractor advice goes... Im removing a 12 foot load bearing wall and doorway and replacing it with a beam between the kitchen/dining room. I am thinking of going the overbuilding route.

My idea is to use 2x 1.75x12" lvl beams with one side going straight to the foundation via twin jack studs and the other going to a lally column in a 2x2x2 footing via twin jack studs. I will hang the floor joists of this beam on joist hangers. The only thing being supported is a bedroom floor above, no other walls or roof.

Thoughts?

Eta: 10 foot joists on either side. So basically this beam will support a 21x12 foot floot above it, right down the middle.

I was considering 3 lvl beams but thought it may be overkill. My FILs cape house has an longer span with smaller beams and has been fine the last 25 years.

Mike



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