Porcelain tile cracked from cold
We have a 2-year-old home in Northern Michigan with a screened porch where we installed porcelain tile. We love the tile flooring. First winter in the house, no problem. But this past winter (probably colder overall) some minor cracking occurred. It’s near the edges of the porch where snow or moisture could have acculumulated, although we have deep eaves and are in the woods so very little snow blows in. The grout separated away from the tile, and there are cracks in 3 tiles, all of which are irregular shapes to go around posts and such.
My questions:
What’s the best way to go about repair?
Can we wait on repair as long as we keep moisture off the cracks?($$)
Is there a certain grout that might be best?
I have a feeling that the grout is what failed, allowing moisture under the tile, which caused the cracking. Can anyone confirm that?
Since only the irregularly shaped tiles cracked, should we cut all repair tiles in rectangular shapes to minimize this risk?
Thanks in advance.
Replies
What's the best way to go about repair?
Remove the cracked tiles with an air-chisel, clean off old thinset, reset.
Can we wait on repair as long as we keep moisture off the cracks?($$)
If they crack more will it make the repair more difficult? No. Will the cracks in those perimeter tiles cause cracks in other tiles? Only if you have new freeze-thaw cycles, which at this time of year is questionable. But you do want to keep water from seeping into the entire structure of your tile base, so yes, keep it dry until you repair and reseal it.
Is there a certain grout that might be best?
Polymerised sanded floor grout.
I have a feeling that the grout is what failed, allowing moisture under the tile, which caused the cracking. Can anyone confirm that?
From your description it was probably not the grout which failed, but the sealer. If the grout had been mixed with too much water or not properly slaked, the entire grout job would have disintegrated instead of only the area near the edge. You did apply sealer to the grout...?
The other possibility is that you didn't flash the edges of the floor properly; if that's so, draining rain or snow-melt could weep back under the floor through the edge.
Since only the irregularly shaped tiles cracked, should we cut all repair tiles in rectangular shapes to minimize this risk?
Yes, that would probably help. 'L' or 'U' shaped tiles custom-cut to accomodate posts are notoriously prone to cracking.
Finally, the question you didn't ask: Could frost heaving of my entire deck structure have anything to do with this? For which the answer is, yes. If your deck moves up and down with freeze-thaw cycle of the ground because the support posts do not have proper footings below the frost line, nothing you do on top of the deck will prevent that tile job from cracking.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
Dinosaur, thanks for that thorough response. The deck is set on 2'x2' concrete footings that extend well below the frost line. Weeping is probably not an issue as this area gets barely a mist of rain during a downpour. As far as sealing, I don't know, but I will check with our tile guy when he comes back to repair it. He's got a good reputation and we've had no problems with the bathroom tiles he set, so I'd assume he did that.
If the tiles that cracked were around the posts, and the space between the cracked tiles and the posts was grouted...It could be movement of the post (seasonal expansion/contraction) that is putting pressure on the grout which in turn is putting pressure on the cut tiles and thus causing the cracks.If that might be the case, then replace the cracked tiles but caulk the gap between the tiles and the posts instead grouting. The caulk will allow for a bit of post movement without affecting the tiles.This is a wood deck? That was tiled? Do you know what the tile was adhered to? Plywood, cement board, a transition membrane or some sort? The damage around the edges of the floor could be due to moisture or temperature, it depends on what the subfloor makeup is and how it was detailed during construction.Mongo
Edited 4/25/2008 11:58 am ET by Mongo
It could be movement of the post (seasonal expansion/contraction) that is putting pressure on the grout which in turn is putting pressure on the cut tiles and thus causing the cracks.
Good call, Mongo. I should have thought of that possibility, too.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
The caulk idea sounds good, Mongo. This is a screened porch with a plywood subfloor. I'm not a builder, don't know the lingo, but there was some sort of plastic gridlike stuff laid under the tile. :)Do you really think that the posts could be moving, given that the porch is set on such large/deep footings? Or are you talking about swelling of the wood with humidity? The porch is 10x17 and supported by three 2'x2' square concrete footings. I'd estimate that the footings are 10' tall, and dirt was backfilled onto them so only about 3' is now exposed above ground.
everything moves.
usually in more than one direction.
it's when two things move at different rates that U have potential problems.
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
I'm not a builder, don't know the lingo, but there was some sort of plastic gridlike stuff laid under the tile. :)
That's Ditra (or an off-brand imitation of it). It's a combination of waterproof membrane and bond-breaking interface. As Jeff Buck pointed out, it's the different expansion rates of different materials that causes things to go skrank. The Ditra has a stretchable fleece membrane bonded to the bottom of that plastic 'waffle', and that is what's actually glued to the subfloor. It 'disconnects' the tile from the wood just enough to allow each substance to expand and contract at its own rate without affecting the other.
What Mongo was talking about was swelling of the posts. If the tiles surrounding them were notched to fit and grout was forced tight into the space between the wood post and the cut tile, well, you can see what the the result would be.
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Hi Dinosaur
Have you tiled a few decks in the snowy Mt Tremblant area. I'm stockpiling some porcelain tile for my own deck. Of course my own house is last one to work on. It will be freestanding on either I joists or 2x10 with two layers 5/8 tongue and groove screwed and glued. I was contemplating using the schluter ditra that Holmer always uses but I want somebody other than him to recomend it. We have alot of snow and winter here but the ski hill next door is alot smaller!
What thin set have you used on an outside deck?
Are the Habs going to beat the Flyers?
Have a good day
Cliffy
I've done a couple, both with heated living space under them. I make a sort of mega-sandwich when I do these.
From the bottom up, it goes 1¼" ply subfloor; Blueskin¯ roofing membrane; thinset; ½" Durock¯ CBU screwed on 8" centers; thinset; Ditra¯; thinset; tile; grout; sealer.
The thinset between the membrane and the CBU is there only to fill any voids that might be left even after screwing it down on 8" centers; it has no adhesive value here because nothing sticks to the top side of Blueskin. I usually run a grid of laser-level shots to find any serious hollows or bumps and trowel the stuff on accordingly.
Although I hate working with the stuff, it's probably better to use an unmodified thinset all around on jobs like this where there are multiple impermeable layers to hold the moisture in: modified dries by evaporation; unmodified sets by chemical reaction. (Anyway, Schluter specifies unmodified.)
Whatever type you decide to go for, you'll use a lot of it. Figure triple normal consumption. The Ditra waffle eats up most of that. And Definitely use the Ditra anytime you've got a doubt. The stuff is magic. Homer? Who dat?
Habs/Flyers? My boy and his friends are counting Canadiens flags on all the cars they see (they got up to 500 on a round trip down to MTL for his birthday), but I gave up on the NHL when the Nordiques moved to Colorado....
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Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Thanks for the quick response. YOu sure put alot into the decks. At my house the underside is just an outdoor slab. The deck is about 30 inches up and I'm going to enclose the bootom to hide flowerpots in the off season etc. I never even thought of usiong Blueskin their.
Holmer is Mike Holmes. He uses ditra on everything he does except in the first few seasons but I don't respect his knowledge enough to value his opinion.
Do you think with the salary cap and all that bus that Quebec City would be able to keep an NHL team. I know Winnipeg and Hamilton are hopeful. Same deal in Boston with Canadians and Canadien fans. My nephew (from Ontario) is at MIT for grad school so he and his chums go to the two games at the Boston Garden. He told me that alot of Boston fans were incredibly rude to the Canadians, before during and after the anthem. It was an eye opener for them.
I think the Habs have met their match.
Have a good day
CLiffy
Bear in mind that particular Dagwood Sandwich recipe was for decks which were also roofs (over heated living space); that's why I used the Blueskin. But everything else was for the tile.
The one thing I didn't mention in that post is that you've got to flash the edges very carefully so that you don't have any way for water to weep in there. I think I may have mentioned it earlier in the thread, but Schluter makes a tile-mould/drip-edge/gutter system specifically for this type of application. It's pretty pricy, though; you might want to take a close look at how it's built, and then see if your local tin guy can custom bend you some colour-matched stock to do the same thing.
Do you think with the salary cap and all that bus that Quebec City would be able to keep an NHL team
Apparently not. But it was nice to have two teams to root for in this province: one for the Montréalers and the other for all the rest of us, LOL. The year the Nordiques went up against the Habs for the Stanley Cup was awesome. Reminded me of a Yankees-Mets 'subway series'; lots of friendly ribbing amongst friends rooting for opposite teams.
If that idiot coach hadn't pulled Hextal out of the net, we woulda taken 'em!! Last hockey game I ever watched....
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
Edited 5/1/2008 11:08 pm ET by Dinosaur
My deck won't be a roof really but I was thinking about how to flash the edge. It is going beside (but one floor lower) another little deck that has vinyl floor membrane and on the edges it has a little flashing similar to a drip edge. Then under the drip edge I have plain white fascia coil down to some perforated soffit. I was planning on doing something similar on this deck.
Thanks for your input.
If you ever meet John and Candy Gill in or around Tremblant say hello from Onaping. They are our former neighbours that moved over to ski all winter.
Have a good day
Cliffy