Gravel for concrete?
#1
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Gravel for concrete?
I'll be pouring some footers for a deck soon. I know I need to have 4-6" of gravel under it, but I'm wondering what kind of gravel/rocks I can use?
I ask cause I have about 1000lbs of marble chips that I dug up and have nothing to do with. I know it's over kill, but can I use the marble chips for a base?
I ask cause I have about 1000lbs of marble chips that I dug up and have nothing to do with. I know it's over kill, but can I use the marble chips for a base?
#2
Basically any stone, exotic or not, that will create air gaps but maintain rigidity will work. I don't see a problem with marble chips. Their main purpose is to allow water to drain through and not puddle up in the hole.
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Ok I'm getting ready to do this, I dug the hole out tamped the dirt at the bottom with a 2x4, then added 5" of marble chips and tamped that, but no matter how much I tamp it it's still pretty loose. I'm just paranoid cause I've seen some stuff say to use a "compatible gravel". Is it possible the marble chips are too big?
#5
The chips, or gravel for that matter won't "compact". They are as compact as they will get when you pour them in the hole. You'll be pouring concrete in a sonotube with them anyway. That weight alone will compact anything.
#6
Most gravels will take compaction quite well, because of the uniform gradation of sizes. Meaning a blend of fines, medium and coarse particles to interlock with each other. Your chips lack the fines and medium particles, so as you've learned, they will not compact and take a set. Sprinkle in some sand if you want them to firm up before adding concrete, although doing so isn't really necessary. They aren't going any where.