Porcelain tile outside over wooden deck porch

SEYON

I have just installed porcelin tiles over existing wooden porch deck using lightweight concrete board and used flexibond motar cement for exterior use and I am now being told that it probably will not hold up through the winter. I live in cincy oh.

gregzoll

Write back next year, but pictures will be nice.

Nestor_Kelebay

Wow. That porcelain tile is going to be slippery as anything once it gets wet or you have a layer of ice on it.

What you need to be concerned about is rain water in the fall getting in under the tile and freezing at night. As water freezes, it expands, and your mortar just can't stretch very far. The likely result would be that the expanding water would pop the tiles off.

Ron6519

A wooden porch deck is not a substrate you put tile over, in any climate. Any sort of research would have told you this.
Ron

BenH

Perhaps I'm misunderstanding him, but it seems he used hardibacker or somthing of the sort first ( if that is what he means by lightwieght concrete board )

To be honest, it probally wasn't the best idea........

But......... no one can tell you for sure if it's gonna "pop". More than likely thats all it will do. If you sealed the tile and grout well, it may not do anything at all.

However like someone else already pointed out, it will be VERY slick when wet.

Ron6519

I'm sorry, maybe I wasn't clear about this. The stated structure, is inappropriate for tile, even if it has a backer you would use as a component of a proper tile installation.
With 30 years in the remodeling field, I can say with little doubt this install will fail.
And you do not seal porcelain tile.
Ron

almypal

Ron states that it is innapropriate to tile a wooden porch with backerboard, but doesn't state why. I would like to hear why Ron if you happen to still be around! Unless Ron has a good reason that I have not thought of, I cant see why it should not be successful, as backerboard is a solid base for tile, together with the use of an uncoupling agent it would help to make sure any movement in the wood (covered by backer board subflooring) due to temperature fluctuations will not affect the tiles. Also, porcelain tile does not allow water to enter it, unlike ceramic tile. That is why it is used in swimming pools.

almypal

....Correction, porcelain is 0.5% porous

Renovator,LLC

Its not the tile itself that is the weak point in this application (assuming porcelain tile is used), but rather the grout. The grout may allow water to penetrate beneath the tile, then freeze/thaws cycles would probably cause failure.
Or maybe not. I talked to Schluter about an outside porch tile project (which didn't happen) here in New England, and they were confident that if you used their Ditra as an uncoupling membrane, failure shouldn't happen. I forgot to ask about the moisture-thru-the-grout scenario with their Ditra, which, imho, would result in the same failure.
Anyone have first hand photos of full weather-exposed tile work, tested by time in a freezing climate?

AtlanticWBConst.

Sadly, this project is doomed for the reasons stated. The deck itself is not a stable structure for the installation of tile. Add the harsh weather elements of the region and you a have a recipe for the tile failure.

Sorry.

__________________
- Build Well -

Ron6519

You don't tile a wood porch because it's a wood porch. Meant for sitting on and rocking. It's made of 2x4's or 2x6's usually placed wider then 16" on center with slat boards on top. Putting cement board (not a subflooring, by the way) over the top adds no structural support or integrity to the floor. Cement board needs to be put on a solid base ,it doesn't provide one. The porch floor will have too much bounce and thereby fail.
The OP didn't say he restructured the porch to specifications needed to achieve the necessary deflection rate, he just said he put, "lightweight concrete board" down. This was either a lack of understanding or cheap/ stupid. Either way it fails. And the time, effort and cost will go into a dumpster within a year or so.
Wasting time, "sealing " porcelain tile is idiotic.
Ron

almypal

Thanks Ron and others!

Very good point about likely bounce / movement. However, this particular porch doesn't have "slat boards" but has exterior grade plywood 3/4" thick as the flooring (it is no different to the interior of the house which can be tiled once cementitious backerboard is layed -apart from interior grade instead of exterior grade plywood being used inside). Of course it is different in that it is subject to weather.

However, I could back up even further. The actual original problem was this: The exterior porch plywood was likely originally skimmed with a levelling compound and then painted with grey porch paint. The oil based porch paint showed thin hair line cracks. I made an original attempt at fixing this by lightly sanding and priming, then covering with two coats of latex based porch paint (which I though would have enough give to allow for slight movement). Looked great for a few months, then the hairline cracks re-appeared (at random accross the surface) THAT'S when we got into discussions about porcelain tiling with the client.

Obviously it would be great if anyone could suggest a quick fix, where we don't have to resort to tiling.
In the meantime I found a site where they have tiled a porch with porcelain tiles (it is at harborfarm.com)



Outdoor Porch

On the second floor is a flat roof over a porch and covered tractor entry. Equipped with in-floor heating, it is tiled with H.F.’s RH Series through-bodied porcelain in a natural stone-type finish of a greenish-gray color. Because it has no glaze, moisture cannot get between the body of the tile and the glaze. The V-cap edge, however, is of H.F.’s BG Series stoneware tile in Sea Green.

Incidentally, doesn't subflooring include anything under the finished surface.

Thanks again!

ccarlisle

The crux of the matter of why you don't tile outdoor structures made of wood is because the substrate expands and contracts at greater rates than tile and mortar do, so cracking is inevitable. Cracking leads to water penetration and tile failure. Ditra and other antifracture membrances are meant to minimize this phenomenon and are successful INDOORS but don't have a chance against sun, rain and freezing etc.

I think I read somewhere that Ditra can withstand substrate movement of 0.1%. Outdoor wood expands about 1-2% depending.

Flexibond is an organic adhesive, isn't it? What some call a mastic. I don't care much for what the sales literature says but organic emulsions (i.e mastics) re-emulsify under water and very wet conditions. They break down. Result = tile failure. No pro I know uses mastics near wet conditions except for the odd replacement of a tile in a backsplash, maybe. Nowhere else...

Sealing grout only prevents staining, not water penetration. And porcelain tile doesn't 'seal'...can't. Oh ya...and the cbu will just be a water-sponge. One frost and "ALL GONE"

The 'veterans' who have posted here are right.

Tjim01

.....So what's the best options for such a project? I have a wrap-around porch I'm interested in covering. I know there are composite planks made for this purpose - but a bit pricey. Any other options??

Bud Cline