Laying tile

[EatenByLimestone]

The house is getting resided. Project creep necessitated that the 42” wide by 30” deep entry be redone too. After I broke out the 3” of concrete (I thought it was only going to be 1/2”! I kept moving up in hammer size.) I put in 3/4” ply down to level and then the 1st layer of Hardybacker.

I noticed that the floor tips back toward the house ever so slightly when we got a hard rain last week. I’d like to correct that before covering everything up and forgetting about it until something exciting happens.

Gutters will soon be installed and that will effectively increase the overhang by 5-6” so it might not be an issue, but water being pushed back at the house is bad practice.

I will be laying another layer of Hardie down to cover a piece of trim I forgot about when I put the first layer down. Should I fix the slope with some thin set before I put the new Hardie down, or should I put the Hardie directly down on the old one, then add more thin set (thicker in back, thinner in front) under the tiles themselves?

All my previous tile work has been inside and I didn’t care if there was a little pitch to the tiles.

[Snipe Hunter]

I don't understand. You are using tile backer outside?

[EatenByLimestone]

Hardie Backer. It’s waterproof, or at least supposed to be.

[EatenByLimestone]

Is there something different or better that I should be using?

[mad_planter]

Is there something different or better that I should be using?

I don't think Hardi backer is meant to be used that way;  And did you say you put plywood down?  This is outside in the weather? I would think you'd want to put concrete back down and tile on that.

[brnhornt]

I don't think Hardi backer is meant to be used that way;  And did you say you put plywood down?  This is outside in the weather?  I would think you'd want to put concrete back down and tile on that.

Caveat, I'm no expert, but I agree.  I personally would rip up the Hari and plywood.  Clean the existing concrete, put down a bonding primer, pour a "pad" to the thickness and slope you need.  Install Schluter Dita (or other decoupling membrane) and then tile on top of that.

[Snipe Hunter]

Yea... no plywood outside. Asking for trouble and fast.

I guess it depends on the sub-surface. If it's concrete, I clean the concrete and tile over it.  Not a fan of Hardie Backer only because I think it's harder to work with than Durock. I do use something like Red Guard, it acts as a decoupler and helps prevent cracks. But so does Hardie Backer or Durock. Sidewalks, porches and patios tend to settle  downwards toward the house because of the disturbed soil near the foundation. So do HVAC condensers.

I'd either replace the concrete or use a primer and a topping compound and re slope it downward away from the foundation like it was when installed... but it still might settle again. Maybe even mud-jack if it made sense.

It's a good idea to use an epoxy grout and a polymer modified thinset outside or in any wet location. You can also use a latex additive to the grout to help prevent water getting under your tile. The epoxy works better. Try to find a slower setting epoxy. I made the mistake of using a pro-fast setting and I wasn't fast enough to use it without making a mess of things.

[Snipe Hunter]

Wish I had progress pics of this but this is 2x2x3/4" porcelain tiles over concrete, just Redguard on the concrete. The steps were really bad. The last tile job was awful and a lot of water got below the tiles and the steps so loose tiles and cracked concrete from ice. The steps had settled about 2" on one side and 1 " on the other side and negative slope. I power washed what was left of it and built forms and poured a topping compound on both steps to correct the slopes. I dug below and around each side and poured concrete to the frost line for better support. Hope that shores it up. The steps only had a 12" deep foundation/footing below.




Some of these tiled popped right off, some took a lot of work. Used a Harbor Fright air chistle... 1" A lot of work but worth the effort and a HV diamond grinder wheel on an angle grinder to smooth out the stubborn grout.

[Cabinet Monkey]

Hardie Backer.  It’s waterproof, or at least supposed to be.

NO -  IT IS NOT !  



:no




It is water resistant       That is something all together different.

Reg. ol HardieBacker ain't approved by anyone for use outside.
HardieBacker 500 is approved IF you live in the Sunbelt or along the Pacific Coast.  Anywhere else.....NOPE !  incld. NY.
If in you use 500 outside you've got to also use waterproofing membrane and proper flashing detail too. Which you ain't got.
Thinset is not suitable for fixing slope regardless or type or brand  
 


Sorry to be that guy but:

YOU SHOULD DEMO EVERTHING YOU'VE INSTALLED AND TRASH IT !


FORGET ABOUT HARDI ANYTHING FOR OUTSIDE.




Now, you can start to remedy your slope problem at the source.  Make the porch STRUCTURE slope away from the house BEFORE you add any type of subfloor or finish floor.  Which should not involve HardieBacker.

[EatenByLimestone]

This is why I posted. Tiling isn’t my thing. I wish I could post pictures. This isnt a deck. It’s part of the floor structure of the house. My front door is set back in from the outside wall by 30”.