Building an ADU in Idaho — from zero
One homeowner, no permits yet, and Idaho's brand-new ADU law.
I'm building an accessory dwelling unit on my own property in Post Falls, and documenting every step of it here. The research, the costs, the surprises. See the live build tracker →
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September 3, 2026
Does an ADU need its own water and sewer connection? Post Falls' answer changed.
In July the city told me an ADU has to share the main house's water and sewer. In August Tisha Gallop, a city permit tech, told me that isn't true. Separating runs about $11,000, and there's a cheaper way I didn't know about.
September 1, 2026
The young man who knocked on my door selling pest control
A young man in his mid-twenties knocked on my door selling pest control. He wants to own a home, and he's thinking about leaving Idaho to afford one. Same math my own sons are doing.
August 6, 2026
Does an ADU need its own gas and electric meter? I called Avista.
Avista quoted about $1,000 to $2,000 to trench for electric and nothing for gas. Then I asked about my other lot in the same city and almost none of it applied.
August 4, 2026
The arguments against more housing, including nine I can't answer
I've been making the case for building more homes in Kootenai County. So I wrote down every serious argument against it, including the ones I lose. Nine of the twenty-two are still open.
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