ADU rules in Troutdale, OR — also called accessory dwelling unit regulations or granny flat ordinances — cover setbacks, owner-occupancy, parking, and permit requirements.
TDC 8.170 allows up to two accessory dwelling units per legal primary single-family dwelling — one must be an interior conversion or attached, and the other detached. Each ADU is capped at 800 square feet or 50% of the primary dwelling, whichever is smaller.
Under TDC 8.170(C), two ADUs per legal primary dwelling are allowed: one attached or interior, plus one detached. Attached or interior ADUs use a Type I procedure under TDC 6.900; detached ADUs require Type II review. TDC 8.170(D) caps each at 800 sq ft or 50% of the primary dwelling, whichever is smaller, except an interior-conversion ADU may occupy a full floor. Detached units must sit in the side or rear yard and cannot exceed the primary dwelling's height. ADUs follow the underlying zone's setbacks. Attached units must match the primary dwelling's paint and exterior materials. In the MU-3 district, TDC 8.230(B) limits ADUs to attached or interior only.
Building an ADU without the required Type I or Type II approval, or exceeding the 800 sq ft or 50% size cap, is a code violation. Community Development can issue stop-work orders, require corrections, or pursue abatement and civil penalties.
Troutdale, OR
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Troutdale, OR
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Troutdale, OR
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Troutdale, OR
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Troutdale, OR
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Troutdale, OR
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