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

A new ADU was going up on a wooded lot outside Kalama, and we wired it from the architect’s plans. It has its own panel, circuits run through the open framing, boxes in every room, and wiring for the covered porch lights.

Why an ADU gets its own panel

An ADU is a separate place to live, so it needs its own shutoff and its own breakers. Nobody should have to walk to the main house to reset a breaker. We run one feeder from the main service to a separate panel in the ADU.

That also forces an honest load calculation. Before we size the feeder, we make sure the main service can carry both buildings. An ADU adds a second kitchen, water heater and heating system. Getting that feeder size right the first time is the main thing in 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, we followed the plans room by room:

1. Ran each circuit from the new panel through the ceiling joists to its first box
2. Set the boxes on the studs at the heights and spacing the plans call for
3. Pulled wire through the porch ceiling for the outside lights
4. Kept every hole in the studs and joists within the drilling limits for its size

On new construction, rough-in is when you get it right. Once insulation and drywall go up, moving an outlet means cutting walls.

Permits in Cowlitz County

Kalama electrical permits go through Washington L&I’s office in Kelso. A new home means a rough-in inspection before the walls close and a final once everything’s 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 framing.