[Tjsb]

I have 8 foot deep concreate walls (on the inside)for a garage,what and how should I fill it for the slab.

Thanks Tom

 

[Scuba_Dave]

How much are you filling?

 

[RippySkippy]

I get a product called "man sand" from a limestone quarry. It's nothing more than course sand screened from the stone crushing process. It doesn't bridge when filling tall spaces, doesn' require much packing...works well. I don't recall the price per ton...but it was cheaper than "normal sand"

 

[yesitsconcrete]

depends on how heavy the loads'll be that you're placing on the floor AND what the base material's like,,, my garage floor's 5" thick & has 8" graded aggregate base compacted in 2 4" lifts over ga clay,,, think some call gab crusher run, item 4, or even ' mansand ' :laughing:

if you're filling 8' between the ' concreate ' walls, be a good idea to go no more'n 8" lifts.

 

[jomama45]

My vote would be for 1.5" to 2" fractured stone , if you can easily find it locally. It's a little more expensive than pea stone, but performs much better. 2" fractured stone also fills more area per ton, although it may cost slightly more. If I remember correctly, most larger fractured stone is something like 95% to 97% compacted dumped directly out of the truck. I cant say I've poured on sand backfill in a garage, especially 8' worth, since the 1980's, when it was more acceptable. When you figure the time & water needed to "flood" sand to completly settle it, it's a waste IMO.

 

[Tjsb]

Im filling in 8 feet with pea gravel so far unless there's something better.

 

[Just Bill]

Pea gravel drains well but is a poor base for concrete, it does not compact well. As suggested above, crushed stone(crusher run), compacted makes the best base.