Quick question on ground prep before slab poor

[JBAUTO]

Hey guys i have a 24x24 garage attached to my house. I am taking the floor out as we speak as it was cracked due to not being packed down and not having any rebar or mesh.

Now the fill under it is sand.

What should i do. Im doing in floor heating and will be doing this ontop of the recommened fill.

thick vapor barrier and then my 2" thick foam then wire mesh with the pex attached to it.

I have read best bet would be crushed stone compacted down then some earth compacted down then a thin layer of sand under the vapor barrier ext

Any advise thanks alot.

 

[Ord]

I am interested in this too, I am at the same point. The builders here are telling me to use only clear crushed stone (no fines) so that there is no chance of settling or shifting.

 

[gatchel]

2B stone (or #57, same thing) is usually what's used as a base under concrete around here.

 

[Zeke]

It really depends on the soil condition below the sand. Wet sand is not a bad base for concrete over certain soils. If you don't know and can't get a soils report, then to be safe you can try and compact a blend of aggregates. For stable soil that is undisturbed, most concrete contractors would spread sand, place the barrier and tie the steel. The problem with sand is that it gets roughed up with all the foot traffic. But, the bottom of your slab doesn't need to be perfect, it will lay on whatever you place it on.

 

[Motown 454]

I work construction, and was grading on the interstate and found a section of sand. I was going to remove it and put in dense grade materal. The engineer was near so I asked and he told me sand is good to build on if its contained it will keep its strength. He was a smart kid .

 

[JBAUTO]

So im guessing the best bet would be to wet the sand there now and compact the **** out of it?

 

[ddawg16]

Code here is....

Solid base....it can be rock if you want...but needs to be compacted.....translation, new construction needs to be compacted...but if you pulled your old foundation off it....it's already compacted....

Depending on how rough it is...maybe a then layer of sand....

Vapor barrier

2" of sand......

but sense you are doing the pex....I guess the sand would be under the vapor barrier...the foam...then pex....rebar...

Make sure the vapor barrier goes down at the edges. You want any water that seeps onto the plastic to have a way down to the ground.

 

[JBAUTO]

So basicly im creating like a giant bag so that water wont go up into the foam. Perfect

So im going to compact the **** out of this sand and level it and then proced witht eh build.

Thanks alot guys

 

[Bib Overalls]

Around here compacted "builder's sand" is commonly used under slabs like the one you described.

 

[JBAUTO]

Perfect guys thanks alot. ill post up some pics of the work