Kitchen Tile

[countryhouse]

Hello everyone:


A few years ago the members here helped me with a bathroom radiant heat ceramic tile project.

Now I am doing the kitchen a similar way. I put 3/4" plywood (glued and screwed)on top of the tongue-and groove subfloor. Then I routed a 5/8" wide by 1/2" deep round-bottom groove in the plywood for the PEX with heat plates. I am about to put 1/4 HardieBacker on top of the plywood with thinset and the special hardieBacker screws. My question is, how soon can we walk on the HardieBacker after installing it with thinset and screws?

I am installing wood-look tiles from Lowes (Nott Gunstock 6x24). I need to pick a thinset for the tile. How would CBC Flexbond work with these tiles? I am putting down about 250 square feet of tiles and if I need to spend more for a good thinset I will.

I searched through previous posts on the 6x24 wood-look tiles and didn't come up with a consensus on trowel size. Would 1/2x1/2 be ok or is it too large?

Thanks

[cx]

Welcome back, Steve.

1. You first evaluated your joist structure to see if you qualified for a ceramic tile installation without improvement?

2. Your "tongue-and groove subfloor" was sawn boards or something else?

3. Your type of glue and method of application was......?

4. Your 3/4" second layer of subflooring was oriented perpendicular to the joists?

5. You don't need to wait at all after installing the Hardibacker to walk on it. You do recognize that your application isn't likely to thrill the manufacturer, though, right?

6. If you mean Custom Building Products (CBP) Flexbond, yes, that would be fine for your application. The bigger consideration is the flatness of both the tiles and the subfloor. You must have a very, very flat subfloor to facilitate easy installation of those large format tiles.

7. I would start with a much smaller notched trowel and check to see what kind of coverage I was getting on the back of my tiles and adjust as necessary.

My opinion; worth price charged.

[countryhouse]

Thanks for the reply.

1) My situation is an odd one. There is a concrete slab under the kitchen floor with a basement under it. Then they put 2x8 joists on top of the slab to make it level with the rest of the house (which uses 2x12 joists). The joists are shimmed every 3 or 4 feet to the slab, which means the floor is rock solid from a bending point of view. The only reason I added the 3/4" ply was to contain the radiant tubing. If I had routed out the tongue-and-groove it would have been weakened (1/2" deep grooves).

2) The tongue and groove subfloor was sawn boards about 5" wide, originally nailed down but I added 2" deck screws.

3) I used subfloor adhesive from caulk tubes and then also screwed down the plywood every 8" or so with deck screws.

4) Yes, the plywood was perpendicular to the joists and I made sure all seams didn't line up with any tongue-and-groove seams. Also, no Hardibacker seams will go over any plywood seams and the hardibacker has no 4-point corners.

5) What part of my application wouldn't thrill the manufacturer? The radiant heat part?

6) Yes, it is CBP Flexbond. I believe the floor is very flat, but I will check for sure before any tile installation.

7) What notch size should I start with? I have a 1/4 x 1/4 trowel.

[John Bridge]

Hi Steve,

1/4x1/4 or 1/4x3/8. 1/2x1/2 is probably too large.

I'll wait for CX to weigh in again, but we usually recommend a layer of plywood over plank sheathing . . . without the grooves. I'm a little shaky about your proposed installation.

[cx]

3. That's always a little problematic as you can end up with your top layer of subflooring spanning whatever gaps you have between your beads of adhesuve. Type of adhesive, speed with which you got the second layer fastened, how you weighted the second layer, etc., all have a bearing on that, but it's generally not a good idea at all.

5. No, they care not at all about the radiant heat, it's all those gaps in the plywood and the potential lack of a proper fastening schedule that the CBU manufacturer might find concerning. If you pre-fill all those gaps around your hydronics with an appropriate patching compound and let it set up, then cover the whole thing with the prescribed mortar bed, then install the CBU following the manufactuer's fastener schedule without poking any holes in the tubes, it might work out OK.

Keep in mind that the absolute minimum requirement for any tile installation over your board subflooring is a layer of nominal half-inch exterior glue plywood. You've got some plywood there, and it's not too far from some of the manufactured panels used for that sort of hydronic installation, and it's entirely up to you whether you think it's adequate. I think some of that is what JB is concerned about, too.

Maybe you could post some photos of what you've got?

My opinion; worth price charged.

[MAPEI - Technical Service]

If you're buying your tile at Lowes, you can buy the Porcelain Tile Mortar there as well. It should be suitable for your application (porcelain tile over backer board).

[countryhouse]

Here is a picture of the radiant tubes/heat plates installed:






Steve

[countryhouse]

I had previously asked about using CBP Flexbond for the wood-look tiles and the consensus was that it was OK to use.

What about the TEC TotalFlex Mortar? Since I am buying the tiles at Lowes I might as well buy the mortar there. I Emailed TEC, described my application, and they said it would work properly.

I am asking just in case someone had a negative experience with the TEC.

Thanks
Steve

[Davy]

Hi Steve, I've never used Tec but I'm sure someone here has. I'll bump you back to the top.

[countryhouse]

I am about to install tile in the kitchen and have a few questions for the great folks here on the forum.

A few background items:

The tile is 12x12 terra-cotta look porcelain from Lowes.

The substrate is 1/4 Hardiebacker board applied with screws and thinset.

The floor structure is rigid enough. It's also pretty level, not perfect but good.

I am going to use CBP Flexbond.

Now the questions:

1) I am thinking of using the Raimondi Leveling system. I have read threads on it and it seems to work good. Not being an expert on tile laying (I'm doing this for my house) but having done tiles before, do you think this system will help me with lippage? It's reasonably priced (compared to the other systems) and I am willing to use it.

2) Because of various issues (time, money, etc) the Hardiebacker was installed a few months ago and the family has been using the kitchen. There are some small localized stains and the surface doesn't appear as clean as it was new. Should I lightly sand the surface to ensure the Flexbond sticks properly?

Thanks everyone for sharing your knowledge and experience.

Steve

[cx]

This the same kitchen floor with the sawn board subfloor and hydronic heat, Steve?

1. Haven't used that system. If you'll use the Advanced Search feature you'll find some threads about it, though.

2. Without seeing your floor it's difficult to determine the condition of your CBU surface. A light scarification might be in order or just a good cleaning. Not sure just how Hardibacker will react to sanding, never tried it. You might wanna contact their tech services people on that question.

[countryhouse]

Yes, the same kitchen floor! Obviously it's taking a long time to complete. You have a good memory.

1) I guess the real question I need answered is not whether any particular leveling system is better than another, but do you guys think I have a reasonable chance to lay the floor without significant lippage without resorting to levling systenms?

2) Good Idea. I will contact Hardie tomorrow.

Steve

[countryhouse]

Well its been a while but I finally have the tiles laid.

The suggestion from the manufacturer was to clean the Hardiebacker board with a stiff nylon brush and a small amount of water. This cleaned up the HB board really well.

I used CBP Flexbond to adhere porcelain 12 x 12 terra-cotta look tiles from Lowes with 1/8" spacing.

I am looking for suggestions on the grout to use.

I would like a premixed grout.

In my bathroom, I used the SpectraLock epoxy grout, but it would cost too much for the large kitchen area (250 sq ft).

It would be nice to use a grout that doesn't need sealing.

I was looking at the Fusion Pro, but it seems to have some mixed reviews on the forum.

Thanks
Steve

[Houston Remodeler]

Fusion is all we use. Don't seem to have any of the problems mentioned.

[countryhouse]

I was hoping to hear that about the Fusion Pro.

That's what I'm going to use for the grout.

From what I have read in previous threads, the key is to "wipe as you go" instead of doing a large area and then going back to clean and shape it like with regular grout.

Did anyone have any problems with the odor/vapors? The manufacturer's data sheet says to provide "adequate ventilation". I am generally very resistant to chemical vapor effects but I would like to know. It's pretty cold here lately, and if I have to open windows it might get too cold for the Fusion Pro.

Thanks
Steve