Concrete

TxBuilder · 09-30-2006, 09:36 PM

I am correct that dumping Quickcrete into a hole THEN pouring water on it is not good at all? The water is not going to pentrate and not form concrete correctly right?

Big no no?

Square Eye · 09-30-2006, 10:09 PM

With a steel post.. I've been guilty of doing that.
Even not adding water at all, just tamping the concrete in and leaving it.

Never had a failure.

If it's acceptable to tamp rock into a post hole, why not bagged concrete?
I believe that in a damp climate, like here in the spring and fall, the moisture will eventually penetrate and set the concrete.

Opinions vary.

If an engineer specifies concrete, you'd better mix it first.

TxBuilder · 09-30-2006, 10:44 PM

In question is wood 4x4 fence posts set 2' deep.

Square Eye · 09-30-2006, 10:56 PM

Concrete has a corrosive way of destroying wood. If you wrap the posts with a builder's paper (tar paper) first, you should be fine. Put rock in the bottom of the hole and adjust the depth with more or less rock. The rock will leave the bottom open to drain any moisture and is easy to work with. When you get the height right and the post aligned, then pour concrete in up about a foot, final adjustment, tamp, fill the hole in, tamp, top off the hole, tamp again. Recheck your plumb and alignment, move on.

Just be careful to not rip the paper while tamping. Trim off the excess paper when the post is set.