Can I build a backyard home in Fife?
Since 2023, Washington law lets most city lots hold up to two more homes. Fife writes its own rules on top. Here’s what the code says, in plain English — and a free report on what may fit on your lot.
What Fife allows.
The headline standards. Tap any one for the full wording and the code section.
ADUs per lot2Full wording
2 — 'Up to two ADUs are permitted on a legal lot of record, if the lot meets the minimum development standards for the zone'; one attached ADU on a lot below the minimum lot size; duplex, triplex and townhome structures are limited to one ADU (FMC 19.80.030(A)).
Max size1,000 sq ftFull wording
1,000 sq ft — 'Each individual ADU shall be no larger than 1,000 square feet' (FMC 19.80.030(C)); an attached ADU inside existing legally permitted space may be larger, if still smaller than the principal residence, with director approval (FMC 19.80.030(H)). No exclusions stated.
Max height24 ftFull wording
24 ft, or the zone limit if lower — an ADU must 'be equal to or less than the height of the applicable zoning designation, or 24 feet, whichever is smaller' (FMC 19.80.040(A)(1)); the LDR limit is 30 ft or 2 stories (FMC 19.51.010).
Front setback20 ft in LDR (same as the house)Full wording
Same as principal: 20 ft in LDR, plus 20 ft of driveway between a garage or carport and the front line (FMC 19.80.030(E); 19.51.010).
Side setback10 ft in LDR, one side may be 5 ft (same as the house)Full wording
Same as principal: 10 ft interior yard in LDR, one side may be 5 ft (FMC 19.80.030(E); 19.51.010; 19.68.020(B)); 5 ft abutting an alley used as sole access.
Rear setback10 ft (same as the house); 5 ft at an alley used for accessFull wording
Same as principal: 10 ft — Fife treats every non-front lot line as an 'interior yard' (FMC 19.06.395; 19.51.010); 5 ft abutting an alley used as sole access. No ADU-specific alley lot-line rule found.
Lot coverage40% for structures in LDRFull wording
40% for structures in LDR (FMC 19.51.010); green area factor 40%.
Parking1 per ADU, on top of the house’s; none near major transitFull wording
1 space per ADU in addition to the primary residence's parking (FMC 19.56.040 table); none for ADUs within one-quarter mile walking distance of a major transit stop unless on-street parking is infeasible (FMC 19.56.020(D)). RCW 36.70A.681(2)(a)(i) bars requiring parking within one-half mile.
Where a city figure reads stricter than the state floor (RCW 36.70A.681), the floor may control — the report flags it for your parcel.
Living there, selling it, plans, time and fees.
Each answer is the code’s own wording, with the section it comes from. “Not published yet” means the city hasn’t posted a figure — the report asks the city, not the internet.
Are backyard homes allowed?
Yes — 'Accessory dwelling unit (see Chapter 19.80 FMC)' is an accessory use in the LDR district (FMC 19.14.030(A)); ADUs may be attached or detached, and legally permitted detached accessory structures may be converted (FMC 19.80.020(E), 19.80.030(A)–(B); Ord. 2140, 2025).
Minimum lot size
Two ADUs need a lot that meets the zone minimum; a smaller legal lot gets one attached ADU (FMC 19.80.030(A)). LDR minimum lot area: 7,200 sq ft (FMC 19.51.010). See Notes for a conflicting rule in FMC 19.68.020(A)(2).
Do you have to live there?
No — Chapter 19.80 FMC (Ord. 2140, 2025) contains no owner-occupancy requirement; former FMC 19.80.020(A) was repealed by Ord. 2140.
Can it be sold on its own?
Yes — a property with an ADU 'shall not be subdivided but may be segregated in ownership from the principal dwelling unit, such as condoization' (FMC 19.80.020(D)).
Pre-approved plans
None found
How long the city takes
Not published
Impact fees
An ADU counts as one-half of a single-family residence for school, traffic and park impact fees and for water and sewer general facility charges (FMC 19.80.060).
Plans Fife has already approved.
A pre-approved plan skips the design review: Fife has already checked the drawings, so the permit review is about your lot.
Loading the plans…
Pictures are the official pages’ own. A pre-approved plan is not a permit: the city still reviews your site.
The code is half the answer. Your parcel is the other half.
Lines and easements
Where the lot lines really are, which setbacks apply on each side, and whether a utility or access easement takes the corner you had in mind.
Critical areas and slope
Steep slopes, wetlands and streams come with buffers that no citywide number shows. The report reads the county’s maps for your parcel.
Sewer, septic, water, trees
Whether sewer reaches the lot or it’s on septic, where the water service is, and which trees a city protects — the things that decide where a unit can actually go.
What Fife allows, what could fit on your lot, and a planning cost range. If something won’t fit, the report says so — and shows what might.
Where this page comes from.
Read from the Fife municipal code and the city’s own pages on November 5, 2026. The same table feeds the HousUp report, so the report and this page never disagree. Cities amend their codes; before you design anything, confirm the current wording with the city.
8 sources, read November 5, 2026
- www.zoneomics.com/code/fife-WA/chapter_27 (FMC 19.80)
- www.zoneomics.com/code/fife-WA/chapter_18 (FMC 19.51.010)
- www.zoneomics.com/code/fife-WA/chapter_20 (FMC 19.56)
- www.zoneomics.com/code/fife-WA/chapter_4 (FMC 19.14)
- www.zoneomics.com/code/fife-WA/chapter_23 (FMC 19.68.020)
- www.zoneomics.com/code/fife-WA/chapter_2 (FMC 19.06.395)
- official code https://ecode360.com/FI4442
- RCW 36.70A.681 — the state floor for accessory dwelling units
Find out what your property could become.
Type your address. Within a few hours: what Fife allows, what could fit, and a planning cost range. Free, no obligation.