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1804.3 Backfill Organic Material???

G

Gardner

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Jan 17, 2020
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Chatlottesville, VA
So I caught a concrete sub for a builder today back filling a basement well with stone that is to be topped with structural concrete for a homes front porch. Unfortunately they back filled over organic material including a hay bale, multiple pieces of lumber and food waste bags. (I took a picture prior to backfilling). I am in virginia and building code section 1804.3 states the requirements for back filling which I believe is also the national code. The builder is saying it doesn't matter because the concrete is structural (containing rebar). Any input would be appreciated. I know it is not good practice, but is it against building code?
 
The issue is not with the porch slab support but rather with section 1804.3. I don't know but I've been told that slabs are usually not a structural element. Now let's suppose that the slab was designed by an engineer to span over a void (odds are slim that it was)....that still doesn't satisfy section 1804.3 So I would not accept any excuse and it is a code violation.

1804.3 Placement of backfill. The excavation outside the foundation shall be backfilled with soil that is free of organic material, construction debris, cobbles and boulders or with a controlled low-strength material (CLSM). The backfill shall be placed in lifts and compacted in a manner that does not damage the foundation or the waterproofing or dampproofing material.
Exception: CLSM need not be compacted.
 
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ICE said:
The issue is not with the porch slab support but rather with section 1804.3. I don't know but I've been told that slabs are usually not a structural element. Now let's suppose that the slab was designed by an engineer to span over a void (odds are slim that it was)....that still doesn't satisfy section 1804.3 So I would not accept any excuse and it is a code violation.

1804.3 Placement of backfill. The excavation outside the foundation shall be backfilled with soil that is free of organic material, construction debris, cobbles and boulders or with a controlled low-strength material (CLSM). The backfill shall be placed in lifts and compacted in a manner that does not damage the foundation or the waterproofing or dampproofing material.
Exception: CLSM need not be compacted.
Click to expand...

So how the porch is designed has no bearing on the failure to comply with section 1804.3. They are not code compliant and should remove the gravel backfill, remove all organic material, then reinstall the gravel?

They said they were just using the stone as a base and it wasn't even necessary. I almost said in jest that pouring it on plywood would be way cheaper. I decided to consult code instead and get others opinions. Thanks for the thoughts.
 
Gardner said:
So how the porch is designed has no bearing on the failure to comply with section 1804.3. They are not code compliant and should remove the gravel backfill, remove all organic material, then reinstall the gravel?

They said they were just using the stone as a base and it wasn't even necessary. I almost said in jest that pouring it on plywood would be way cheaper. I decided to consult code instead and get others opinions. Thanks for the thoughts.
Click to expand...

It is still a violation that needs to be corrected regardless of the type slab being poured. There is not exception in the code based on type slab above. Have him correct it and move on.
 
The lumber will attract termites. They need to get rid of all the organic material as required by code.

It's also best to make them do things right from the start. There's no telling what another sub might try to pull as the job goes along.
 
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Will it be an issue, probably not. Could it be an issue, definitely.

Have it removed. Contractor should do it right, irrespective if the risk is low.
 
I agree with the veterans, these contractors did a hack job and might very well be testing you. I would be very comfortable giving them grief.
Here's what our code says in British Columbia, I hope it indirectly helps you :)

9.12.1.1. Removal of Topsoil and Organic Matter
1) The topsoil and vegetable matter in all unexcavated areas under a building shall be removed.
2) In localities where termite infestation is known to be a problem, all stumps, roots and other wood debris shall be removed from the soil to a depth of not less than 300 mm(12") in unexcavated areas under a building.
3) The bottom of every excavation shall be free of all organic material.​
 
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