Hey all! Anyone out there ever poured an overhead concrete deck? I lived at a place out in WA that had one but I can’t remember what the bracing below looked like. I know you can use ICF’s that are made to go between garage floor and basement ceiling but this is just an outdoor deck so the ICF’s wouldn’t be useful other than not having to build forms. Anyone with any experience with this? Your words of wisdom would be greatly appreciated! Thanks.
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why concrete?
No words of wisdom, but interest.
(I'm looking at doing an glassed-in 2nd story passive solar collector sun room which would have a concrete deck under tile to absorb/radiate heat to the surrounding living spaces. The ICF forms wouldn't be ideal for this project, so we're loooking at corrugated steel form deck. But I've never worked with it, so I guess I'm piggy-backing on your post.)
what's the scoop on your project? span? location? motivation?
k
My brother did it. It was supported by block walls and a couple of concrete columns. He formed it with plywood underneath and removed all the plywood afterwards. Commercially I've seen them use corrugated steel under it that is left on. But there is still considerable bracing that is removed.
It would have to be engineered, wouldn't it?
More than one.
And more than one way to do them.
Engineer is highly recommended, reinforcing requirements need someone who knows what they are doing!!
I have used "Pan deck" which looks like corrugated metal roofing but is a heavier gauge. Suppliers have span tables and bracing guides available for small projects, large decks get an engineer to spec out bracing for you .
(actually I have also used metal roofing with bracing for small decks, simple 3' wide walk ways.)
Also can be done with plywood forms and bracing, Or with forming lumber and lots of bracing.
Commercially available support scaffolding can be rented to support the forms when being poured. Most large concrete supply houses have info on the supports and bracing requirements. Some pics of that style scaffolding are posted below. Plywood deck was laid on top of the scaffolding "I" beams
One thing to remember is that you have to build a camber into the forms because the concrete will settle after it is set and the forms are removed.
Another is that this is not a job to be taken lightly. A collapse of the forms is not a pretty site and can , if workers are on the deck at the time, be very dangerous. Several tons of wet concrete in the wrong place isn't a wonderful way to spend a day.
Here is a pic of one deck being formed on a winery .
Hey thanks for your reply! I'm gonna check out Pan Deck and make some phone calls. This particular project is in the design phase and we're just brainstorming. It's a residential job and very modern. We're all excited about the possibility but it may end up being too expensive. Your projects looked awesome. Thanks again.
Some good replies and good advice. My question is does it have to be poured? Precast has always been more economical on my concrete projects (lots of factors come into play there such as using the same forms lots of times, material prices and the fact I have two very large precast co.'s very close to me). It may not work for smaller projects, but there are lots of different precast options. It has been great on my projects to have the precast co. take care of everything and go from a poured in place foundation to finish work in a week and a half on a 30,000 SF building.
I had an engineer prepare cast-in-place plans for my 30' span (very high load). Proved incredibly expensive compared to the bar joists/steel decking/unreinforced concrete slab I used.
PAHS Designer/Builder- Bury it!
Must have been a serious wind blowing the string when that wall was built. < G >
"Doubt is not a pleasant condition, but certainty is absurd."
~ Voltaire
LOL... We are on top of what passes for a mountain here. At least it blew the string the same on both walls.
Otherwise, placing those bar joists would have been interesting. PAHS Designer/Builder- Bury it!
Now with that bit of additional information, again, why pour ceement?
You want a raised overhead concrete deck with out the high cost of supports framing, etc? Read this link:
http://forums.taunton.com/tp-breaktime/messages?msg=91581.1
It'll give you whatever design characteristic of ceement you desire. All but the weight.
Cool project! I'll keep it in mind. I don't think this particular project is the right for trying something new. I'm actually a sub on the job and the general won't go for it. There is too much money involved and reputation and all that. We're here in Minnesota also. I'm wondering how your system would hold up in 20 below zero weather. I'm wondering what it will look like in 5 years. How thick is the concrete/mortar? I'd be worried about flaking and cracking. Maybe on a less serious job or with a real penny pinching, adventurous client.
But of course! I dropped 100 grand on that project in Western Michigan as a simple experiment.
Something new? To you maybe. Before you blow off new technology of which you simply are unaware, maybe a phone call to the manufacturer would - could - provide a touch of education...
As to your question, 3/4" thick.
Hey I was just relaying some concerns/questions in my head. I'm a new contractor and just trying to provide quality work for folks. Maybe I'm a little bashful about something new, but you seem a little defensive. Sorry if I somehow offended you. As I've said already- thanks for your reply to my post and nice looking project.
I embedded links to the products used. Those links provide a means to contact the manufacturer. May I suggest educating yourself before dismissing something that possibly could make you stand out from your competition.
Note on the website there are training sessions. In sunny California.
Call the company and have them send you their information on the Miraflex II deck system. And the independent lab's testing report. While you're at it, ask whom carries the products in your area and a phone number for the regional rep. He will answer any question you may have. Including pricing. Here's a brief description:
http://www.miracote.com/index.php?href=productdetail&id=9
Edited 4/11/2008 11:28 am ET by peteshlagor
I've been doing a bit of research into systems similar to the miracote. They are more common than I thought. We are going to be doing a concrete deck overlaying a finished area and the debate will be a system like miracote or an overlay system from someone like Scoffield or Elitecrete or a membrane....Lots of choices. Indicently, our concrete sub will do a concrete deck with only posts supporting the ends: no beams or walls. He builds a temp deck and pours the slab with the proper reinforcement, then pulls all the shoring out. It's a pretty impressive system and comparable to trex pricing. We haven't had the opportunity to sell one yet but I'm hoping for one soon. Bob's next test date: 12/10/07
You're absolutely correct. There are many firms. And some of the work being done by some with these products are incredible! And fairly priced.
Have you looked into precast, prestressed concrete members? We used them for our garage floor (wanted a shop underneath). Set in place, poured a slab over top, and if I wanted, I could probably do something to the underside as well to pretty it up. Cost about 5K for the precast for a 30x24 area.
5k installed? that's not bad.
k