Conduit penetration through pre-fab building wall

[philly]

I have a new installation where I need to get new conduits (3-2" & 2-1") from an outside location to inside of an existing pre-fabricate electrical building. The conduits are being routed underground in PVC conduits over to the existing building.

The existing pre-fabricated building walls are approximately 3" thick.

My thought was to stub-up PVC conduits at exterior of building wall and transition to go up the exterior of wall with rigid conduit and then use LB conduit fittings to penetrate the wall. New conduit fittings will be installed with appropriate fire barrier caulk or puddy. Once inside the building the conduits would continue as rigid conduits overhead inside of the building.

Interested to hear any feedback or other suggestions for transitioning UG conduits to penetrate through existing building.

Thanks

 

[drktmplr12]

might want to consider if the structure is pre-tensioned, or x-ray before core drilling to ensure you don't damage any tendons, if there are any.

 

[mull982]

might want to consider if the structure is pre-tensioned, or x-ray before core drilling to ensure you don't damage any tendons, if there are any.

Thanks. To me smaller individual conduit penetrations are less damaging to structural integrity than a larger cutout for cable tray opening.

Is core drilling usually the preferred method for drilling through a steel prefab wall?

 

[drktmplr12]

Thanks. To me smaller individual conduit penetrations are less damaging to structural integrity than a larger cutout for cable tray opening.

Is core drilling usually the preferred method for drilling through a steel prefab wall?

The implication is that the prefabricated building is steel panels fastened to a steel superstructure, and not pre-cast, pre-tensioned concrete. We call it a pole barn down here. If yes, you should have no issues with drilling holes or creating openings in any of the sheet metal walls as they are not designed to carry load. i would not drill any holes into beams or columns.