Can I build a backyard home in North Bend?
Since 2023, Washington law lets most city lots hold up to two more homes. North Bend 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 North Bend allows.
The headline standards. Tap any one for the full wording and the code section.
ADUs per lot2Full wording
2 — 'Principal residential units are permitted to have two ADUs.' (NBMC Table 18.10.050 row 1.52(a), Ord. 1825)
Max size1,000 sq ftFull wording
1,000 sq ft — 'ADUs shall not be larger than 1,000 square feet.' (NBMC Table 18.10.050 row 1.52(c)); the old 800 sq ft / 10%-of-lot cap and one-bedroom limit were deleted
Max height25 ftFull wording
25 ft — 'Detached ADUs shall not exceed 25 feet in height to the highest point of the ADU structure.' (NBMC Table 18.10.050 row 1.52(f)(iii)); accessory structures also 25 ft (NBMC 18.10.041(E))
Front setback20 ft in LDR (same as the house)Full wording
Same as principal: 20 ft in LDR (NBMC Table 18.10.040 row 4(a)); 'Detached ADUs shall meet the bulk and dimensional standards applicable to the principal unit' (Table 18.10.050 row 1.52(f)(ii))
Side setback5 ft minimum for a detached ADUFull wording
5 ft minimum for a detached ADU (NBMC Table 18.10.050 row 1.52(f)(ii)); LDR principal standard is 5 ft one side, 15 ft total (Table 18.10.040 row 6(a)); 10 ft on the street side of a corner lot (row 1.52(f)(iii))
Rear setbackNot confirmed yet — 10 ft or 25 ft; ask the cityFull wording
Not confirmed yet — ask the city. (NBMC row 1.52(f)(ii): detached ADUs 'shall meet the bulk and dimensional standards applicable to the principal unit and maintain a minimum five-foot side yard and 10-foot rear yard setbacks', while the LDR principal rear yard is 25 ft (Table 18.10.040 row 7(a)); unclear which governs. A DADU may sit at a lot line on a public alley not routinely plowed (row 1.52(f)(v)))
Lot coverage40% building coverage for a single-family lot with an ADU in LDRFull wording
40% building coverage for a single-family lot with an ADU in LDR (35% without) — 'LDR-4 35%/40% sfd/sfd w/ADU' (NBMC Table 18.10.040 row 9(a)); impervious surface 65% (row 10(a)); ADUs must meet both (Table 18.10.050 row 1.52(e))
Parking1 per ADUFull wording
1 per ADU — 'Residential accessory dwelling unit and rooming houses, similar uses | 1 per dwelling unit' (NBMC Table 18.16.090); ADUs must meet parking rules (row 1.52(g)). City staff say North Bend has no major transit stop (Feb. 5, 2025 staff report)
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 — 'An ADU may be attached ... or detached (i.e., incorporated in a garage or other outbuilding to the principal dwelling)' (NBMC Table 18.10.050 row 1.52(b), Ord. 1825); ADUs are 'P' in LDR, CLDR, MDR, HDR and NMU and some commercial zones (NBMC Table 18.10.030 row 1.52)
Minimum lot size
None for an ADU — 'ADUs do not require additional lot area other than that required for a single-family dwelling' (row 1.52(f)(iv)); the old 4,000 sq ft minimum was deleted. LDR new lots: 7,500 sq ft minimum, 8,000 sq ft average (NBMC Table 18.10.040 row 1(a))
Do you have to live there?
No — Ord. 1825 deleted 'The primary dwelling unit shall be owner-occupied' from NBMC Table 18.10.050 row 1.52
Can it be sold on its own?
Yes — 'ADUs may be sold as condominiums subject to preparation of a condominium map per Chapter 17.24 NBMC.' (NBMC Table 18.10.050 row 1.52(d), Ord. 1825)
Pre-approved plans
None found
How long the city takes
Not published
Impact fees
Transportation impact fees: new ADUs appear exempt (NBMC 17.38.040(A)(2) as quoted in the city's April 2025 draft; the city's fee consultant says North Bend 'currently exempts DADUs up to 1,000 SF from transportation impact fees'). A park impact fee exemption for ADUs was proposed in April 2025; adoption not confirmed. RCW 36.70A.681 caps any ADU impact fee at 50% of the principal unit's
Plans North Bend has already approved.
A pre-approved plan skips the design review: North Bend 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 North Bend 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 North Bend 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.
7 sources, read November 5, 2026
- www.zoneomics.com/code/north-bend-WA/chapter_5 (mirror of NBMC 18.10: Tables 18.10.030, 18.10.040, 18.10.041, Table 18.10.050 row 1.52, incl. Ord. 1825)
- www.zoneomics.com/code/north-bend-WA/chapter_10 (NBMC 18.16.090)
- northbendwa.gov/ArchiveCenter/ViewFile/Item/6871 (Ord. 1825)
- northbendwa.gov/ArchiveCenter/ViewFile/Item/6826 (Feb. 5, 2025 Planning Commission staff report)
- northbendwa.gov/ArchiveCenter/ViewFile/Item/6900 (April 16, 2025 impact-fee drafts)
- official code https://ecode360.com/NO4565 (not readable by automated tools)
- 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 North Bend allows, what could fit, and a planning cost range. Free, no obligation.