Redmond ADU Permit Process

Frequently asked

• What is the current Redmond, WA ADU permit timeline?

  Median Redmond ADU permit issuance from clean submittal is 8–16 weeks in 2026. That breaks down as: intake + completeness check (5–10 business days), first review cycle (4–7 weeks across building, planning, side-sewer, addressing, drainage as applicable), corrections back to us (1–2 weeks), second review (2–4 weeks), then issuance. Pre-application meetings shave one full cycle on average. The fastest Redmond ADU we have closed in 2025 was 6.5 weeks on a catalog plan with a pre-app; the slowest was 22 weeks because of a side-sewer easement title issue — not a planning issue.

• What reviews are required for an ADU in Redmond?

  Standard Redmond ADU review touches building, planning (zoning, lot coverage, setbacks), addressing, side-sewer (or septic where applicable), water availability, drainage review (if impervious exceeds threshold), and energy review (IECC R406 worksheet). Critical-areas review triggers if your lot is mapped for steep slope, wetland, riparian, or landslide hazard. SEPA review is rare for a single ADU but possible if other land-use actions are pending on the same parcel. Each review runs in parallel, not sequentially, which is why pre-app meetings matter.

• What gets Redmond ADU permits rejected on first review?

  Top six Redmond reviewer redlines we see: (1) IECC R406 envelope worksheet missing or calculations not matching plan assemblies; (2) side-sewer not shown on site plan with slope and invert; (3) lot coverage math omits roof overhangs (count to drip line in Redmond); (4) Fire separation between primary and ADU walls insufficient when separation < 5 ft; (5) glazing U-factor or SHGC on schedule doesn't match window NFRC labels; (6) drainage report missing when impervious increase is over the threshold. We catch all six in our QA before submittal.

• Can I expedite the Redmond ADU permit?

  Redmond does not offer formal paid expedite for residential ADUs, but the practical accelerators are: catalog plans (reviewers see familiar details and move fast), complete drainage report at submittal, pre-app meeting on file, and using a contractor whose past submittals were clean. We track our own correction count per submittal; clean sets average 1.2 review cycles in Redmond versus the city-wide 1.8 average. Pre-app meetings are free and currently scheduling 3–4 weeks out — book one before drawings start.