DADU feasibility · Ravenna & Bryant
Building a DADU in Ravenna & Bryant
Ravenna and Bryant combine large lots with heavy tree canopy — the trade is space to build against trees you may not be allowed to remove.
This profile is measured from City of Seattle open data across 7,789 parcels in Ravenna/Bryant — not estimated, and not the same numbers as any other neighborhood on this site.
Lot sizes in Ravenna & Bryant
Lots skew comfortably into the 3,200–7,200 band with a strong tail above 7,200. Physical fit is rarely the binding constraint here.
Parcel counts by lot size, Ravenna/Bryant. Source: King County parcels via Seattle's ADUniverse dataset.
53% of parcels here are under 5,000 sq ft and 47% are 5,000 sq ft or larger — a middling share among the 18 areas profiled here. Seattle repealed the old 3,200 sq ft minimum lot area for a DADU, so small lots are no longer excluded; they are simply governed by the floor-area budget instead.
What the ground looks like
Flat and stable ground, but a high share of peat settlement-prone soil and one of the higher canopy percentages in the city. Tree tiers under SMC 25.11 are the realistic risk to a Ravenna DADU, not slope.
Ravenna & Bryant against the median of the 18 Seattle areas profiled here. Hazard layers clipped to the neighborhood boundary; canopy is area-weighted by census block group.
What decides feasibility here, in order
Ranked by what this neighborhood's own measurements say — not a generic checklist.
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01
Side sewer, water and electrical capacity
44% of buildings here predate 1940 and 31% were built between 1940 and 1975. Older stock means older side sewers and smaller electrical services — the two utility findings that most often reset a DADU budget.
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02
Physical fit on a small lot
53% of parcels here are under 5,000 sq ft. Lot size no longer disqualifies a DADU, but on a tight lot the lot-wide FAR and lot-coverage budget — which ADU floor area now counts toward — usually binds before setbacks do.
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03
Protected trees
Tree canopy covers 30.1% of Ravenna & Bryant (Seattle median here: 26.9%). Seattle's tree code (SMC 25.11) protects trees by tier, and a Tier 2 tree with its root protection area falling across your rear yard can move or shrink a cottage even on a large lot.
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04
Liquefaction and soil conditions
8.7% of Ravenna & Bryant sits on mapped liquefaction-prone soils (Seattle median here: 8.7%). This rarely stops a project, but it changes foundation design and belongs in the budget before you price a build.
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05
Slope and landslide-prone ground
3% of Ravenna & Bryant is mapped as steep slope (40% or greater) and 0% as potential landslide area, against Seattle medians of 7.7% and 4.4% across the areas profiled here. Land inside an Environmentally Critical Area under SMC 25.09 triggers additional review and, in practice, a geotechnical report before design.
Zoning and utilities
Zoning mix
- SF 50006,595 parcels
- LR3230 parcels
- LR1215 parcels
- LR2155 parcels
- RSL137 parcels
86.4% of parcels are Neighborhood Residential or Residential Small Lot; 9.1% are Lowrise. Zone labels reflect the parcel dataset's legacy single-family categories, which map into today's Neighborhood Residential zone under Ordinance 127376.
Housing age
- Before 194044%
- 1940 – 197531%
- After 197523%
Largely pre-war and early post-war. Expect to verify side sewer condition, and expect at least one significant tree in the rear yard to enter the conversation.
Ravenna & Bryant DADU questions
Can I build a DADU in Ravenna & Bryant?
In almost all cases the zoning allows it. 86.4% of parcels in Ravenna & Bryant sit in Neighborhood Residential or Residential Small Lot zoning, where detached accessory dwelling units are permitted, and Seattle removed both the old minimum-lot-size test and the owner-occupancy requirement. The real question is whether a compliant cottage physically fits your lot and whether utilities can serve it.
How big can a DADU be in Ravenna & Bryant?
The citywide caps apply: 1,000 sq ft of gross floor area for an ADU with up to two bedrooms, or 1,200 sq ft with three or more. On top of that, your lot has a single FAR and lot-coverage budget shared with the existing house — which is what actually limits most projects. 47% of Ravenna & Bryant parcels are 5,000 sq ft or larger, so whether you reach the cap depends heavily on which block you are on.
What is most likely to block a DADU in Ravenna & Bryant?
Side sewer, water and electrical capacity — 44% of buildings here predate 1940 and 31% were built between 1940 and 1975. Older stock means older side sewers and smaller electrical services — the two utility findings that most often reset a DADU budget.
Do I need a feasibility study before designing a DADU in Ravenna & Bryant?
You are not required to have one. But the checks that decide feasibility — setbacks against the existing house, FAR headroom, tree tiers, mapped critical areas, side sewer condition, and construction access — are all cheaper to answer before you commit to an architect or a plan set than after. In Ravenna & Bryant specifically, start with the trees — at 30.1% canopy, an arborist's read on tier and root protection area often determines where a cottage can sit.
Next step
Run these checks on your own Ravenna & Bryant lot.
This page tells you what Ravenna & Bryant looks like as a whole. The Seattle DADU Pro Guide walks your specific address through the same review — setbacks and FAR headroom, tree tiers, mapped critical areas, side sewer and panel capacity, the permit roadmap, and a scoring template you fill in yourself.