Pole Barn site Prep

[Sympler]

Hello All, I am having a 20x50x12 Pole Barn built. It will be used as storage/ workshop and size is due to set back and location. I have to handle the site prep work, im going to have 4" of gravel 2" foam and 4" concrete. With that said i figured 3" of concrete sticking out at the highest point for drainage purposes so i would only cut down 7" from the hightest corner( Didnt realise this till it was too late). So i dont do site work usually and i think i messed up, i began cutting the soil down for 24x54 so there 2' working space on each side but i used the driveway as my reference for grade which is about 15' away from the front of the pole barn. So ultimately i cut my site about a foot deeper than i should of, instead of being 7" below the highest point, i am about 19" so the question is, should i just put the dirt back and compact it with my small kubota tractor or do i need to get crushed stone and compact it to make that foot up? And unfortunately the builder is supposed to start building the 26th of February and the permits were approved yesterday so i didnt want to start till they were approved. Any help in this topic would be amazing!

 

[jack stand]

Build it back up with crushed stone. It sounds like you're trying to cut it close to your surrounding grade, a very common mistake from the inexperienced. I'd roughly want my finished slab 12" above the closest existing grade. Remember that the only area's where this is important are entry doors where very little gravel will solve this. There is no easy inexpensive cure for a building set too low.

 

[NUTTSGT]

I'd do stone/gravel in layers, compacting as you go. I'd also make it higher than the driveway like jack stand mentioned.

 

[carlaisle]

Rent a vibratory roller to compact the crusher run/fill. What is underneath the slab is more important than the slab itself.

P.S. Every slab will be jealous of the extra foot of compacted base yours is going to have.

 

[justler]

1ft of stone wont have a large additional cost. Just add it and compact your gravel in lifts (Some say 6", some at 1ft) with a ride on vibratory roller like stated above (Don't do a walk behind plate compactor or remote control compactor). I wouldn't put the dirt back as it's no longer compacted/undisturbed and you may have problems later.

For my site I had the opposite of needing to lift the entire site since it was on aslope (5ft on most extreme side, 2ft in center over 60ft. We did a pad mix, I compacted every 1ft and it's super hard. Did 57s I think it was under the 6" pad non-compacted since the base was solid.

We also set the pad a few inches higher than the rough grade and on the finish grade made a little swale toward the top end of the building to direct water around.