New home Foundation - Backfill

[cr1973]

After the footing and basement walls are poured, how long is the typical cure time before the contractor can go ahead and backfill around the walls?

Assume typical home construction practices...

 

[cvg]

depends on mix design and environmental factors which affect the strength gain of the concrete. Hard to make a recommendation without any information.

High temperatures will accelerate curing, but reduce the strength gain. Low tempereatures will slow down the curing. Admixtures such as flyash will also slow down the process. Many specs requre 7 - 10 days for retaining walls. Others require a minimum strength of 2,000 psi. You should evaluate all of the above to make a decision on your project. Also factor in your risk aversion to cracking the wall and then having to repair it if you hurry it.

 

[cr1973]

cvg, thanks for the info.

 

[oldestguy]

Congrats. New Home.

There is one thing that I find is the cause of more basement wall failures than anything. It's backfilling a basement without any house on it.

At least the deck ought to be there to provide some weight on it and perhaps a little lateral support.

In my case for houses I have built, that deck also has provision to brace the walls, such as with a 2 x 4 nailed under any joists resting on the concrete, or with plenty of anchor bolts.

The longer you can wait the better. These walls are not designed, but they seem to work.

Don't let that backfill get saturated from a big rain either.

Oh yes, if you have an attached garage, no jetting of that fill. The result can be a basement full of mud and
concrete. I once saw a job caved in and the contractor said he has done it for 25 years before and no problems. Well, he doesn't do it any more.