Gravel Base for Foundation Slab Question

[clofgreen]

Can you have too much gravel base under the slab? I'm looking at about six inches of gravel to get the level up to where it needs to be. The other option is to bring in a load of sand and build up the hole that way.

[Mingy]

place a layer of geotextile (the woolly kind) and make sure you pack the gravel down well every time you put a couple inches of gravel. I'd want to make sure the gravel will stay put on the sides - so that may mean making the gravel 6" or so wider than the concrete base.

[Neil2]

The thickness itself is not a problem as long as you compact it well as you go. As mingy notes, two inch lifts with hand compaction will do.

[Mingy]

I find hand compacting a *lot* of work.

Of course, I have my own compactor so I might be biased ...

[benguilford]

Ha! Mingy you are biased, but it's the good kind of biased, the kind that saves your back!

Would you believe I actually hired a vibrating plate compactor for my tiny 1.5m x 1.8m foundation? Split the cost with the neighbor so he could do his too, $25 for peace of mind knowing I had a well compacted base for the slab to rest on. Worth it.