I have been having similar thoughts regarding some sections of my house. Please note that I am not a professional -- so I am just sharing ideas -- not giving absolute advice on the proper way to do it.

I am not sure that you need to add the plywood. Assuming I understand your description correctly, you already have diagonal boards secured to the framing -- this was the "pre-plywood" way to create the stability typically afforded by plywood sheathing today. From what I can tell, most of the concrete backer-board manufacturers (Hardibacker, Wonderboard, etc) do not rate their products for exterior use.....but.....I have used backer-board in my exterior Koi pond structure for years now (as a substrate for tile) and I have had zero issues. A lot of these backer-boards are used for tile installs in bathroom and kitchens -- places that encounter a lot of water. My current plan for the front lower "skirt" on my house (I have decorative rock which is failing at that location) is to first apply a building wrap membrane over the sheathing, attach backer-board, and then tile and finally grout. That is my current plan -- subject to change as I learn more.

Again, I am not an expert, and I am being cautious here, but thus far my backer-board products have held up just fine outdoors as tile substrates.

 

I am needing to use something firm/structural like plywood because I am adding a layer of foam. It is true that hardibacker is not 'supposed' to be used outdoors, however the James Hardie brand does offer a cement siding that comes in 4/8 sheets and I was hoping I could put that on over the foam and then directly tile over that w/o using the lath step.

Ok you say you have a decorative rock that is 'failing'. Can you give details? We were thinking about using the stone veneer but don't know how well it would hold up. I can't understand what keeps it from getting moisture in the little crevices and freezing/busing in the winter? It makes no sense to me.

 

I know nothing about it but that never stopped me.
Why would you not just wire mesh and scratch coat like you would with a stone veneer?
No question about it working well with moisture.

 

why would I wire mesh and scratch coat if I don't have to? Why can't I mortar it directly onto the cement siding? That is m question. And if I do have to wiremesh/scratch coat, do I let it dry or put the tile on that while it is wet?

 

Like I said, know nothing. it was more a question for people who might know the best practice.:vs_cool:

I wonder what insulation value is of the foam board for showers that they tile right on.

 

I have never heard of tiling right on any type of foam board? will google that. didn't know there was such a thing!

 

https://www.schluter.com/schluter-us/en_US/Building-Panels/c/BP

this stuff?

 

yes..............

 

Don't rely on thin insulation board to give you ANY appreciable insulative qualities. Your insulation should be in the stud bays of the home. You won't likely have a good experience with normal porcelain tiles on the exterior unless you take good precautions like drip caps to keep water from infiltrating behind it, freezing and laying your wall over. The Kerdi panels are great, but expen$ive. Your substrate needs to be substantial, so the hardie siding panels could afford that.

How big of an area are you planning on covering? Can you post pictures of the area so we can see what you see?

 

I wouldn't think water would be any different on the wall as tile done on a deck out in the weather.

 

I can't get the pics to work, it is 16 ft wide and about 9ft tall thereabouts.

https://www.lowes.com/pd/Rmax-Therm...am-Board-Insulation-Common-1-in-x-4-ft-x-8-ft-Actual-1-in-x-4-ft-x-8-ft/3014057

what about this?

yes we have insulation in the stud bays. 13? I think.

I do see how water could get behind the tiles and freeze/expand, but I don't understand how that is different using stone veneer. Couldn't water get behind that too?

 

Even with stone veneer, we put cap blocks on it to thwart the intake of water into the vertical stones. With tile, even using a simple cap would keep that water from infiltrating. The difference in vertical and horizontal tile is the horizontal tile will bleed water off, where the vertical tile will allow the water to get behind them, bleed down, freeze and thaw.

FrillyLily, what are you hoping to accomplish by using insulation board?

 

Apparently it is done every day.

 

Good video. Mostly about balcony flooring, but some walls. Note, nowhere was there a vertical wall without a cap or other top protection. Even at 4:00 he emphasized the proper use of flashing.

 

I am hoping to add a little insulation value, cut drafts and maybe make my house a little quieter, we are on a busy street. Maybe it is not even worth the trouble? I don't think it would be that much money to do it and it would be worth it if it helped. But if it is not going to do anything much may not want to put the labor into it? The house is 70 ft long. one side is 22 ft long and then the other side is 42 ft long due to addition. about 1600 sq ft if I remember right.

 

Also the front of the house sits smack on the ground pretty much,I even dug some dirt away from the house that was over the siding and then added some big chunky rocks to hold back the soil. Re-painted, looks decent actually.

 

Window are the worst for insulation and sound.

 

My daughter had frost on the inside of her wall one winter. The mattress was up next to the wall I assume preventing heat from circulating around the wall. It was -15 out, kind of unusual here, bad year. But still our walls are cold. The windows have all been replaced and are new.

 

Were the windows properly flashed and insulated around the framing? Big leaks occur there most often. Can you feel cold air coming through the wall receptacles? Do your exterior doors seal well against their thresholds?

 

I owned a house next to a freeway that had single pane windows and someone had put new double glazed on the inside so there was about 3" between. work well for insulation and sound.

 

There is air coming in around the outlets. I went to the store and bought foam covers that go over the plug, then you screw the plate back on. That seemed to fix it. The house was built in the 40s and has been added onto several times. It had extensive termite damage as well. We treated for that, cleaned up the yard, and repaired all the bad wood. (completely re-built two exterior walls of one room).

Now we are considering these stack-n-tack panels. Any thoughts? Quoted $14 sq ft installed. But we will do it ourselves.
http://www.silverminestone.com/products/

 

On the windows, yes they were insulated, we have filled every nook and cranny in the house with either expanding foam or caulk. The previous owners filled cracks with walmart sacks (!?) and then drywalled over them. Looked great by the way, had no idea they were there by looking, found all this 'underneath' stuff as we went...layers of it.

 

I didn't see any cost factor on the silver mine stone site you linked to, so that would be the only concession I would have. It seems simple enough to install, and it seems as sturdy as you substrate, so make sure that is done well.