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HI Asks: New construction 100% full Panel?

9420 Views 125 Replies 40 Participants Last post by  CraigV
Ok... HI is going to ask a question again.

New Construction, reasonably current code as they had all AFCI's and new Energy stuff....I was doing the final walkthrough inspection...

Question: Can you have an main panelboard that has NO room for expansion on day one?

The Panel was FULL of AFCI's, two Tandem Breakers, and a handfull of wafer (thin double) breakers. There were no open slots. There were no slots that could be converted to wafers becasue they were all AFCI's.

If you wanted to add a single breaker, you would have to add another pannelboard, move two AFCI's to that Panel to make room for it's breaker, and then put the new circuit in the new pannelbaord.

I thought there was a rule that you had to have SOME room for expansion... (remember I don't do code, I leave that to the experts...YOU)

thoughts, comments? (references?)
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· I own stock in FotoMat!
39,048 Posts
90.8 Wiring Planning.
(A) Future Expansion and Convenience. Plans and specifications that provide ample space in raceways, spare raceways, and additional spaces allow for future increases in electric power and communications circuits. Distribution centers located in readily accessible locations provide convenience and safety of operation.

That's all the NEC has to say. AFAIK, if you can rearrange existing circuits to be able to install a subpanel, then it's legal (provided the service is capable of supplying the additional loads).

· Electrical Simpleton
3,343 Posts
I'll add one to 480's...

90.1 Purpose.

(B) Adequacy. This Code contains provisions that are considered necessary for safety. Compliance therewith and proper maintenance results in an installation that is essentially free from hazard but not necessarily efficient, convenient, or adequate for good service or future expansion of
electrical use.

Informational Note: Hazards often occur because of over-loading of wiring systems by methods or usage not in con-formity with this Code. This occurs because initial wiring did not provide for increases in the use of electricity. An initial adequate installation and reasonable provisions for system changes provide for future increases in the use of electricity.


· felonious smile.
15,896 Posts
It still adds up to 40 ckts even if it's a 32/40 panel, doesn't it?

· Registered
8,253 Posts
I thought there was a rule that you had to have SOME room for expansion... (remember I don't do code, I leave that to the experts...YOU)

Although it's good practice, it is not required to leave any unused bus space.

I always install full 40 space resi panels and generally have about 10-15 left open. Sometimes however, they end up stuffed full. Some houses just have more stuff :thumbsup:

· RIP 1959-2015
39,532 Posts
Ok, not required to leave any space...but good practice if you can...

Makes adding that new circuit really expensive....

Oh Well...
Looks like the guy that did the job had a poor game plan and ended up making a mess.

What is the total number of circuits?

· Registered
4,174 Posts
You can't always plan for future expansion.

Should we be required to install pull boxes and pipe to the attic and the crawl spaces? I know that would be a good idea but sooner or later someone is going to end up spending the money. Where would this end?

With the EC getting raped by the GC on a new build, you can better believe it won't be the EC. When every penny counts on those types of jobs, if an EC can save $20 on a panel, you better believe they are going to.

New construction is cutthroat and that's why I don't do it.

But, since the cheap EC installed a 24 circuit panel and now the HO wants to remodel, I can make a killing by selling an upgrade. :thumbup:
1 - 20 of 126 Posts
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