105 MARTIN LUTHER KING JR WAY
Mann · LR2 · 999 sq ft lot
105 MARTIN LUTHER KING JR WAY (Mann, LR2): a backyard cottage is blocked at physical fit — rear-yard clear span is too narrow.
Where the screen stops
Stages are evaluated in a fixed order. A later constraint is only named as the reason once every earlier stage has resolved, so an unknown never gets reported as a failure.
- 1. legal capacityPasses
The verified LR2 rule set permits a detached accessory dwelling unit.
- 2. physical fitBlocked
The citywide screen rejected this lot: DADU blocked: widest clear span behind the house is 13 ft, below the 16 ft cottage width
- 3. financial plausibilityPasses
Under screening rule gap-dadu-financial@v1, modeled income covers modeled debt service at the favorable end of the assumed cost range.
- 4. affordable-program applicabilityNot evaluated
Public program applicability is evaluated only where the physical screen passes; physical fit is blocked for this parcel, so no program conclusion is asserted.
- 5. verification readinessPasses
Every screening input this artifact depends on is present; field verification is still required before relying on the result.
What blocks it: Rear-yard clear span is too narrow
The widest measured clear span in the retained-house envelope is below the 16-foot screening width for the reference cottage. Screen reason: DADU blocked: widest clear span behind the house is 13 ft, below the 16 ft cottage width Lot on record: 999 sqft, regular, no alley access.
- What would resolve this
- Verify rear-yard dimensions on a survey and test a narrower or lot-specific cottage plan.
- Capability this needs
- plan
Limitations of this screen
- Public-data screen only. It includes no site visit, survey, title review, or permit determination.
- Legal capacity comes from joined zone rules; physical fit comes from the citywide parcel screen. A parcel can pass one and not the other.
- The citywide physical screen covers the NR, RSL, LR, MR, HR, and legacy SF residential zone families. Outside them physical fit is reported as unknown, never as a physical failure.
- Current SMC 23.42.022 (Ord. 127375/127376, 2025) allows accessory dwelling units as a housing use in every zone where housing uses are allowed. The former 2023 lowrise principal-unit-type gate and 650-square-foot cap no longer apply; the current cap is 1,000 square feet.
- Detached ADUs are prohibited by the Shoreline Master Program. A parcel is blocked when any portion intersects the official Seattle Shoreline Environments overlay; mapped boundaries still require parcel-level confirmation with SDCI.
- Financial plausibility applies a published screening rule to explicit planning assumptions and a HUD SAFMR rent basis. It is not a bid, quote, appraisal, or forecast, and no Seattle cost calibration supports it.
- The financial stage varies only by ZIP-level one-bedroom HUD SAFMR. All parcels in the same SAFMR geography receive the same result under the citywide cost assumptions; this is not parcel-specific financial evidence.
- Financial geography patterns are rent-basis patterns, not observed construction-cost or project-outcome patterns. They must not be used to deprioritize investment in the neighborhoods they name.
- Public program applicability describes whether a listed program reaches this site. Household eligibility — income, ownership, occupancy, disability, financing — is never collected or inferred.
- The first detected blocker is the first blocking condition under the published stage and within-stage detection order, and attribution is withheld when an earlier stage is unknown. It is not a claim that other constraints matter less.
- Stages are evaluated independently wherever their inputs allow, so a later-stage blocker does not imply that earlier stages passed.
Provenance and reuse
Screen gap-dadu-v1.6 under plan family Backyard cottage / DADU screen, read from the warehouse on . Unlike a published gap brief, this page tracks the warehouse and will change when the underlying evaluation does — cite the screen version and date above alongside the URL.
This is a screen, not a permit determination, and no part of it has been reviewed by the City of Seattle. You are welcome to use it without asking us, and to disagree with it. The full citywide artifact and the methodology carry the rules, sources, and exclusions behind every statement here.