I live in PA, we have fairly bad winters. A potential client is wanting me to build them a patio about 10′ off the ground where it will meet the living level of the house. The HO wants stamped concrete, however, i have been learning more and more that it can be a maint nightmare over a few years and that in our weather it may not hold up very well. Not being knowledgable I can’t say for sure. the HO is open to other suggestions other than stamped concrete. But,….anyone got any good alternatives? Regardless of the alternative there will have to be at least a 4″ thick concrete base since this will be raised off the ground. Would pavers look right, flagstone?
Next question, regardless of alternatives or if stamped concrete, can it be sealed somehow to prevent water seeping thru to the below area which is to become a finished off basement?
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why is stamped concrete any different from regular concrete in maintance.
I wondered that myself to be honest with you. I don't know. I was told you need to seal it every year or two to help preserve its beauty so that it doesn't turn out to be ugly and dingy like concrete tends to become as time wears on. I was also told that the indentations left by the stamping process act like cracks for water to get into and freeze.If at first you don't succeed, try using a hammer next time...everything needs some extra persuasion from time to time. -ME
This deck will be exposed to the elements, right? I've done interior stamped concrete floors over TJIs and ply subfloor that were only 1.5" thick, but of course indoors there isn't the issue of water percolating through the concrete and damaging the subfloor and framing. Even a 4" slab would still render the framing below liable to moisture damage. Putting a poly barrier doesn't help much either, because that will trap atmospheric moisture against the subfloor.
It should be noted that stamped concrete generally stands up well to winter conditions unless it is exposed to lots of salt (ditto for regular concrete). I find it easier to remove snow from stamped concrete because its sealed surface often prevents the snow from sticking - often it can be swept off with a push broom. Plenty of stamped driveways around here.
You mention there was to be usable space below the deck. The only deck membrane I know of that's approved for use over living spaces is vinyl - the ones with trade names like DuraDek. It's pretty cost-effective if the look is acceptable, just frame and apply 3/4" plywood and the Duradek guys do the rest.
The other way it can be done is roll roofing or EPDM over plwood decking, then lay 2x6 sleepers that in turn carry cedar or other decking. I've seen this done on tar roofs where the sleepers were laid right onto the hot tar so they would be stuck down firmly.
I'd expect the Duradek solution to be a whole bunch lighter than 4" of concrete, and therefore supportable by a much less expensive structure. It seems like a no-brainer that concrete 10 ft. above grade is a bad idea here.
-- J.S.
the below area which is to become a finished off basement?
Basement as in "attached to the house's basemnt" or "basement to the outside deck"?
What the term "basement" suggests to me is to design this like a roof deck. So, the weather plane will be what ever it is (roll, single ply, membrane, whatever). The walking surface can then be whatever you want it to be (within reason).
Might actually be a neat effect to make, say, 4'x4' or 6'x6' stamped concrete "pavers" as the walking surface for the deck. The edge details will be the key (along with getting downspouts or scuppers or both, to get the rain off the 'roof').
Now, I've heard some tales of woe about stamped concrete. None from concrete guys, though. The "stamping" is done as part of the finishing process, usually just after raising the cream. The flexible stamp pads should not make surface cracks unless somebody has been ham-fisted with either accelerator or retardant (which is mixed in with the finished tint).
Now, the stamp is making a sort of "control" joint-like feature in the face of the concrete. If the concrete flexes enough to crack, the cracks will 'want' to follow those patterns. That should be no different than any other concrete finish in your region. "Should be" bing the operative phrase.
my driveway is stamp, now there are small, very small stress cracks from forcing the satmo into the concrete but they are no issue. less than a millimeter deep. cosmetic only
less than a millimeter deep. cosmetic only
In other words, same as if you had broom finished, or done a 'float only,' not so?
There does appear to be a minimum thickness, but that seems to be about the same as a minimum thickness concrete slab in any event (that 5/8 - 3/4" thick skim coat with nothing but shredded FG just waon't cut it <g>).Occupational hazard of my occupation not being around (sorry Bubba)
Speaking from the experience of currently _having_ a stamped concrete porch elevated 10' above grade, and from having personally built the structure and formed the pour, there's no reason stamped concrete wouldn't work well. Resealing is as easy or easier than water sealing a wood deck--wash it and roll on the sealer. I did it after 5 years, and it looked new. 2 years is a good interval.
The indentations are generally for short lengths and not deep and part of a pattern meant to disguise any lines, so they should not cause an unplanned control joint (the concrete will do that on its own based on stresses other than the indents) and almost certainly will not cause a crack that's prone to freeze thaw conditions.
If I wanted to argue against it, my two arguments would be that the sealed surface can get really slick when wet, and the structure for such a porch is not insignificant, as someone else pointed out.
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What is the supporting structure under your deck? And is there living space below?Lignum est bonum.
The deck is framed in structural steel supported by the concrete columns and spans about 10' in width. No living space beneath. If there was, it'd need a separate roof.
When I say basement under the patio structure I'm referring to it being the basement of the patio structure. It has no access to the main basement of the house nor does the HO want any. There is to be one entry door to this basement area and it's from the outside.
My steel contractor contacted me today. HE hasn't a clue as to how to prevent water from getting into this basement area. He suggested somehow incorporating EPDM or whatever, but that's it. So my dillema at present is how to keep water OUT of this area. If at first you don't succeed, try using a hammer next time...everything needs some extra persuasion from time to time. -ME
So my dillema at present is how to keep water OUT of this area
Hmm. Like Cloud said, what you need here is actually two things. You need a waterproof roof, and then the finished concrete walking surface.
What that suggests to me is some sort of single-ply roof, with a grid of sleepers over that to support the walking surface. The walking surface could be a very large sort of "paver" to fit. I'd just be leary of any permanently-applied walking surface over the w/p roof plane.Occupational hazard of my occupation not being around (sorry Bubba)
What you can do is have it done like Cloud's deck. Stamped concrete supported by structural steel with galvanised steel Q-deck that will stay in place after the pour. The Q-deck will act as the horizontal part of the form as well as preventing moisture getting through to the space below. The two challenges will be (a) attaching a slab edge form to the steel decking, and (b) finishing a slab where the edge is not accessible from outside the form.
This one will require engineering and it won't be cheap. Get a firm commitment from the client first.Lignum est bonum.
Wille, we've got a 14' wide wraparound stamped concrete deck up on our lake property. It's went through one winter and it come out looking fine. I think we had one or two stone pops.
It was saw cut and it's holding up fine. I wouldn't worry about those decorator cracks causing stress cracks. Just saw cut it into the right size pieces and you'll be all set.
I would worry alot more if I was driving a truck on it.
blue
Thanks for helping not worry too much about the stress cracks :) No truck will be driven on it, so you're right, it'd be more worth worrying about if it was. If at first you don't succeed, try using a hammer next time...everything needs some extra persuasion from time to time. -ME