slate tile on patio,in freezing climate?
well i’ve been tossing around doing a slate patio,my plan is to run a 4″ concrete slab,maybe ditra [i’ll leave that for another time] then slate.i live in wichita ,ks.in the winter we get pretty cold and wet.extreme of zero to -5 is as cold as we get.
so i go to a wholesaler,no problem ,but you will need to seal it probably every fall for a few years.
talk to a flooring store, same story.
so tonight i look at home depots new load of slate ,looks really good. flat on the bottom and pretty flat and tight on the top. so i tell the lady i’ll take a pallet of it. she’s goes into a speil of no way can you use this on a patio around here ,it’s going to freeze and flake and crack etc.if you were in cali ,works great.
now i always take hd advice with a whole lot of skeptisam,but usally it’s something like “yeah you can run your whole house with 1 12/2 wire” or crazy stuff that you leave wondering where they got that.
so whats your input on this?
p.s i already know not to use building bricks for a patio,cause they flake off!!!! larry
if a man speaks in the forest,and there’s not a woman to hear him,is he still wrong?
Replies
I'm watching this with interest, as I'm about to do the same thing, only difference is it'll be under a roof inside a screen porch, but definitely freezing and exposed to the elements to a degree. I'm putting a drain in the middle of the floor so the homeowner can sweep the rainwater off the floor when it gets a big storm. I did slate several years ago in an unheated enclosed porch, and it's been fine.
Steve
Edited 10/6/2008 11:41 pm by mmoogie
The first thing you have to determine is if the 'slate' you're being sold is really slate. Most inexpensive tile sold as 'rustic slate' in big box stores is not; it is geologic shale, which looks similar but absorbs water big time. This, of course, will cause it to crack and flake as soon as it freezes.
True slate, on the other hand, is very dense and will not absorb water; that's why it makes such a good roofing material.
Simple test to determine if the stuff is slate or shale: take a tile and put it in a pan of water for a few hours, then remove it. Shale will leave the water muddy, and will take several days to dry out. Slate will dry quickly and not leave anything in the water.
If you've got real slate, it will stand up to the weather with no problem, but it's still a good idea to slope the slab ¼" per foot for drainage.
You don't need the Ditra if you're going direct on a slab.
Dinosaur
How now, Mighty Sauron, that thou art not brought
low by this? For thine evil pales before that which
foolish men call Justice....
the reason i have mentioned ditra is,if the concrete cracks,and it will it, might not follow through to the tile. i will rebar this patio on 2' squares,so that should hold it together. so you don't think i did any membrain between the two?
i've got some slate soaking now to do your test. we'll see thanks larryif a man speaks in the forest,and there's not a woman to hear him,is he still wrong?
Try accurately weighing the slate before and after soaking it. You'll be able to tell how much water it absorbs. Frost proof ceramic tile is less than 1%. Check something like the Datile website for their specs on outdoor tile.
Yeah, all concrete cracks...but there are cracks and then there are c-r-a-c-k-s.
Obviously, you want to prepare the gravel bed for this slab properly, or all the rebar in the world isn't gonna help. But if you do that well, all you're likely to see in years to come is hairlines. A hairline crack in a slab shouldn't telegraph through, especially something tough like slate. Slate is more likely to flake than to crack like a terra-cotta tile might.
But if it makes you feel better, go with the Ditra. It certainly won't hurt anything except yer budget (and that not much; about $2/sf).
Dinosaur
How now, Mighty Sauron, that thou art not broughtlow by this? For thine evil pales before that whichfoolish men call Justice....
You should have no problem whatsoever, Here in MN I have been on numerous projects where slate was used extensively for outdoor patios with no callbacks. Your best bet is to make sure it is installed properly and you are pitching the water away with no areas where it can pool and settle into cracks, freeze and pop the slate.
Dinosaur gave you some excellent advice.
I did the same thing, concrete pool patio, Ditra, then slate. What I recommend is buy a whole lot more boxes than you need.
When you open the boxes, balance each piece on three fingertips and rap the edge of the slate with your metal trowel.
If it rings, it's a tight piece. If it thuds, set it aside, as it's more "shale" than "slate", in terms of being loosely layered versus having a tight grain.
I have 1800 sqft on this patio and have lost three tiles in I can't even think...maybe five or six years of freeze/thaw? The tiles I lost, one literally disintegrated, the other two sort of split in the middle of the thickness of the tile. The grout held them in place, but when you walked on them after a rain you could hear a "squish" sound as the film of water in between the layers was compressed.
Lost those three tiles over the first winter, the rest have been fine over the past four or five.
I've never sealed it, nor will I ever.
Were I to do it again, I'd buy the thicker 1-1/4" slate (or granite) pavers from build direct. I've bought several containers of stone from them over the years and they're an easy company to work with.
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your deck looks great,i love the look of slate.
so tell me why you would go with the pavers? i had build direct bookmarked for there pavers and was thinking about going that way.biggest problem is buying in that large of quanity.
if you were doing pavers would you lay over the cement or do the base gravel/sand deal?
your definitly colder than i am,why are you against sealing? thanks larryif a man speaks in the forest,and there's not a woman to hear him,is he still wrong?
Thicker, tighter grain, more durable, etc.Around the pool I just prefer a hardscape, so I set them on a slab so I can grout or mortar the joints. Personal preference I guess.For a patio, I'd dry set them over compacted stone dust. I did that with about 1500 sq ft of bluestone patio I have in my back yard.I'll be using the flamed granite pavers for my driveway apron near my house. Hopefully nest year. That'll be over a slab.Sealing? I just don't see a need for it.I've bought large quantities from build direct, used what I needed, then resold the unused for more than I paid.
nice pool ...
when's the Fest?
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa
I already have a horseshoe pit for Calvin. And a plenty big beer fridge for you and me, Jeff.Hey, if I host one, I might even show up for it!
sign me up!
Jeff Buck Construction
Artistry In Carpentry
Pittsburgh Pa