How thick should my footing be?

[black_edelweiss]

The frost level around here is 18"...i dug a 32" deep trench because it was on a slight slope and wanted the whole thing to be perfectly flat. Since my footing is 32" deep, how thick does my concrete need to be? I'll be laying a 8ft tall cinder block wall ontop of it, and building an A-frame on top of that. The width of the trench is about 18" and i'll be running two parallel 1/2" rebar 3" from the bottom.

[Don_P]

8" thick minimum, level on top. You can step it in 8" increments (the height of a row of block) if needed.

[black_edelweiss]

Thanks for the help. One more question- Since im pouring the footing with a concrete mixer by myself and not using a concrete truck, is it okay to pour one side at a time or do i have to pour the whole thing before it dries?

[ChugiakTinkerer]

If you're in an area subject to a building permit authority, you should check first with them as to whether a cold joint in your footing is okay.  A vertical cold joint is more problematic than a horizontal one, as it could potentially allow for a shifting between parts of what is supposed to be a continuous solid mass.  At the very least, you'll want to have rebar and a keyway at the joint, so that when you pour the second part of the footing it locks into the first part.

It would be far better to pour the footing in one go.  That means having all the materials and labor on hand to keep going until the job is done.  If you are concerned about the concrete starting to set, you could work your pour in both directions.  Start at one point of the footing, and alternate batches on either side of your starting point so that you advance the footing pour in both directions.  This ensures that when you make your final batch it won't be abutting the first pour which may have started to set.

[Don_P]

But... the house I'm working on I poured in at least 10 sections, leaving rebar protruding to latch onto and start the next pour.

[ericisagenius]

I would suggest getting a concrete truck, it will cost you but the pour would be perfect. Plus you don't have to worry about the details, etc Like Homer Simpson said "Can't someone else do it" -

[PEG688]

  If you stub out rebar like DonP says you are OK.
 
   BUT unless there's no way to get a mixer truck into the site , I can't fathom why you'd want to work that hard to pour your footings , or foundation , if indeed you'll be pouring a foundation.

But to each there own.


G-luck!

[Don_P]

Here's the op's build thread, looks like he is about done with the foundation;
http://countryplans.com/smf/index.php?topic=14426.0

[PEG688]

  OK , Thanks Don.  Haven't been around the forum lately .

[Don_P]

Good to see you back around PEG