New-Construction ADU Wired From the Plans in Kalama, WA

A new accessory dwelling unit was going up on a wooded lot outside Kalama, and Newman Electric wired it from the architect’s plans. The ADU has its own panel, home runs through open framing, boxes in every room, and lighting feeds for the covered porch.

Why an ADU gets its own panel

An ADU is a separate living space, so it needs its own disconnect and its own place to reset a breaker without walking to the main house. Feeding it with a single feeder from the main service to a dedicated panel in the ADU keeps it that way.

It also makes the load calculation honest. Before the ADU feeder is sized, the main service has to be able to carry both buildings, and an ADU adds a second kitchen, water heater and heating system. Sizing that feeder correctly the first time is the core of wiring a detached building, whether it’s an ADU or a shop.

Rough-in from the plans

With the framing open and the house wrap on, the rough-in follows the plan sheet room by room:

1. Home runs from the new panel through the ceiling joists to each circuit’s first box
2. Device boxes set on the studs at the heights and spacing the plans call for
3. Lighting feeds pulled through the porch ceiling for the exterior fixtures
4. Every bored stud and joist kept within the drilling limits for its size

Getting it right at rough-in is the whole game on new construction. Once insulation and drywall go up, moving an outlet means cutting walls.

Permitting in Cowlitz County

Kalama electrical permits go through Washington L&I’s office in Kelso. A new dwelling unit means a rough-in inspection before cover and a final once the devices and fixtures are in. Our Kalama service area page has other jobs in town.

Building an ADU, a guest house, or a shop with living space in Cowlitz County? Call 360-828-7143 or send us the plan set before the framing goes up.