Concrete Decking

choda_boy_04

I am planning on building a new deck this spring. I plan on doing a 2"-3" slab of exposed agregate concrete for the decking. I am drilling piles to go well below the frostline, I am also going to be framming it with a 3-ply 2x10 or 12 beam (depending on what the code book has to say) with 12"oc 2x10 joists, Then I am going to sheet it with 2plys of 3/4 TIG plywood. So the structure isn't in question, my question I want to create separatation between the plywood and the concrete, so when the wood expands and contracts because it will since I live in a northern climate with freeze thaw cycles. I was wondering if using a ditra mat would work or if there is a cheaper alternative to using ditra?

Thanks

Cody

Termite

I think Ditra would be pretty much essential to keep the wood's movement (inevitable) from destroying your slab.

fixahome

Have you thought about using pan deck in place of the plywood? I have poured several elevated slabs and have always used pan deck over the frame, you could probably use fewer joist also

Knucklez

i like your idea of slab on a deck. sounds strange, but concrete can be beautiful. you might consider some of the techniques that the concrete countertop guys use to create custom impressions, different colours, exposed aggregate etc. lots of tools and stuff available on ebay.

from HD you can get driveway wire remesh (6" squares FLAT not rolled up), 3/8" rebar and probably some fiber in the mix is the way to go to ensure a nice looking & stable finish.

you probably don't want to go thinner than 2.5" because you need the rebar in the middle of the concrete but far enough away from the surface to avoid 'ghosting'.

please show pictures of your project when its done, i'd be very interested in seeing your final product.

Knucklez