duct bank to underslab

[mshields]

I've got a service comming from a pad mounted transformer. Main electrical room is just inside the building. So I'm running a duct bank from the pad mount to under the building. Once I'm under the building I no longer need the duct bank right. But I'm wondering how this transition is typically done? Do I continue my PVC conduits in the duct bank until I get to the steal sweep? Do end the concrete encasement precisely at the building line and continue on with direct buried PVC?

Mike

 

[chris kennedy]

Once I'm under the building I no longer need the duct bank right.

Why would you think you need a concrete encased duct bank in the first place, POCO requirement? What type of service?

 

[mshields]

why duct bank?

why duct bank?

It's a 2000A, 480/277 service to the building which has an ambulatory surgery center residing in it. THey are the larest of two tenants anyway. Yes, it is the utilities requirement. But what I'd like to know is typically how such a transition is made.

Thanks

Mike

 

[luckylerado]

In our area we would only slurry the portion of the ductbank outside the building .

 

[RUWired]

. But what I'd like to know is typically how such a transition is made.

Thanks

Mike

Mike we usually use "stay form". It's like metal lath and comes in 2' high x 10' lengths. Lots of tie wire and rebar holds it in place. We use it when we have future duct banks comming out of man holes and when the ditch is way to wide. It could be a toss up of labor vrs. material. In your case if its not far into the building and the ditch is uniform, the amount of extra concrete may be less than material and labor to secure the load.

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