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City of Billings (MT)

Montana Authority Having Jurisdiction Solar permitting requirements
NEC Code Version2020
Fire Code Version2018 Building Code
Wet Stamps RequiredDigital Structural
Fire Setback Enforced1

Codes

NEC Code Version
2020
Fire Code Version
2018 Building Code
Code List

2021 INTERNATIONAL BUILDING CODE

2021 INTERNATIONAL EXISTING BUILDING CODE

2020 NATIONAL ELECTRICAL CODE

IEBC Accepted
1
ASCE Code Specification
ASCE 7-16

SolarAPP+ & submittal

Revision Required
1
New Planset Required For Module Swap
0

Stamps

Ee Stamp Required On SLD
No
Wet Stamps Required
Digital Structural
Structural Calculations Required
Yes
Stamp Location On Plans
Unspecified
Date On Stamps
Expiration Date

Fire setbacks

Fire Setback Enforced
1

Structural & loads

Wind Speed
110
Wind Notes

https://ascehazardtool.org/

Snow Load
30
Snow Load Notes

https://ascehazardtool.org/

Engineer's evaluation must always show and have a note that states no roof snow loads are reduced below 30 PSF per Administrative Rules of Montana 24.301.154(5).

Reducible Snow Load Allowed
0
Max Attachment Spacing
96
Structural Notes

Engineer's evaluation must always show and have a note that states no roof snow loads are reduced below 30 PSF per Administrative Rules of Montana 24.301.154(5).

Minimum Ground On Roof
#10

Electrical

AC Disconnect Required
No
Electrical Load Calcs Required
Derates
Allowed POI
Meter Adapter,PV Breaker,Line Side Taps,Load Side Taps
Supply Tap Neutral Ground Bond Required
1
Temperature Rating
90
De Rating Ampacity
0.91
BOS Restrictions

Standard

Battery / ESS

Unique Battery Placards Needed
0
ESS Notes

Standard ESS Requirements


When installing ESS in garage add note to site plan: "HEAT DETECTOR WILL BE INSTALLED IN THE GARAGE CONTAINING ESS IN COMPLIANCE WITH R328.7"


R328.4Locations.

Add note to Site plan where ESS shall be installed only in the following locations:

  1. BATTERY IS LOCATED IN DETATCHED GARAGES AND DETACHED ACCESSORY STRCUTURES.
  2. BATTERY IS LOCATED IN ATTACHED GARAGES SEPARATED FROM THE DWELLING UNIT LIVING SPACE IN ACCORDANCE WITH SECTION R302.6.
  3. BATTERY IS LOCATED ON OUTDOORS OR ON THE EXTERIOR SIDE OF EXTERIOR WALLS LOCATED NOT LESS THAN 3 FEET FROM DOORS AND WINDOWS DIRECTLY ENTERING THE DWELLING UNIT
  4. BATTERY IS LOCATED IN ENCLOSED UTILITY CLOSETS, BASEMENTS, STORAGE, OR UTILITY SPACES WITHING DEWLLING UNITS WITH FINISHED OR NON COMBUSTIBLE WALLS AND CEILINGS.
Separate ESS Disconnect Required
No
ESS Elevation Detail Required
No

Plan set

Plan Set Requirements

Photos of existing service required and sub panel (even if not using in POI)


Existing or new sub panel must be protected on either side, cannot do back to back lugs


-BOS Location

-MSP Label/Ratings

-Bussing or feeders of equipment that will be used for interconnection

Cover Page

Standard

Site

Standard

Roof Plan

Standard

Attachment Detail

Standard

Electrical Diagram

If there is any existing equipment such as sub panels, etc. These must be shown within the plans along with the conductor sizes called out

MPU

  • Upgrading service equipment requires an outdoor emergency disconnect
Label Page

PV 7 drop down for MONTANA

Include the label for energy storage systems specified by 706.15(C).

See label example

On Placard:

-Update "AC DISCONNECT" to "PV RAPID SHUTDOWN / AC DISCONNECT"

if AC disco acts as the ESS disconnect, changed label to

"PV RAPID SHUTDOWN / ESS DISCONNECT"

-Include "UTILITY DISCONNECT" with the MSP designator


IF UM IS EXTERIOR AND THE MSP OR MBE IS INSIDE, THE PLACARD MUST INCLUDE THE WORD INSIDE IN THE MSP OR MBE LEADER

Label Page Notes


Custom Placards Required
1
Placards Notes

Custom placards are required on every job inside the City of Billings

Non Standard Revision Requirements

Please cloud all changes

Ground mount

Ground Mount Fencing Required
No
Ground Mount Notes

Standard Ground Mount requirements

Setback Front Yard
10
Setback Back Yard
5
Setback Side Yard
5
Compiled from public records, 2026. Requirements change with code cycles and local amendments. Verify with the City of Billings (MT) building department before you rely on this, and treat it as a research head start, not a ruling. Getting quotes? Run them through the quote checker first.