Crushed rock or plumbing rough-ins first?
New construction, Superior Walls & slab on grade (daylight on 3 sides, against an upslope bank).
After leveling and compaction, the excavator will provide 8″ of crushed stone leveled and compacted for both the Superior Walls (first), then the slab that will be poured to them.
It would be easiest for all if I just bury a few 4″ pipes under the walls to connect to after the walls are up, but I am concerned that when the plumber trenches for his rough-ins, I will get dirt mixed in with my clean rock. Since the rock will serve as capillary break and drainage plane—which will also serve as passive radon collection—will the dirt mixed in be an issue?
On the other hand, my excavator will be standing by with nothing to do were the rough-ins to be done in the soil first. Plus I would have to get the surveyor out twice because he will have to put in pins at the corners for the walls.
Thanks for your help.
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My suggestion is to not try to save time and follow the procedure .
Have the pins set first .
Plumber is next , he can string the walls . Perform the slab rough , test , get inspection . His job becomes much more difficult if he has to move stone to perform the rough . Besides that bedding in the piping properly becomes much more difficult with stone in the mix , granular soil or sandy soil is much easier to do a proper job with .
Then bring in your stone and let the excavator and mason do their thing . Doing this right and in order is much more important than being concerned with people's wants and needs . You'll have no worries with stone mixing with soil , and a poorly installed job because you tries to make better time . It is what it is and variations cause problems .
In my area the plumbers would be pretty ticked off if they didn't have some crushed stone for bedding pipes. If you have sandy soil it wouldn't matter much, but clay soils are tough. We have used 3/4" clean stone as pipe bedding for at least 30 years without a failure.
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Having a bit available is a different story than having to move it along with any soil Rick . Granted if you live in an area where there is an abundance of clay and terrible material rock is a better choice . Having to move a stone soil mix to perform a slab rough however makes the job take 3xs as long and much more difficult .
Rough -in my way is done in sand .... sand and stone bobcated as needed from piles out of the way.