Building permits, zoning and land rules in Kittitas County, Washington

Yes—unincorporated Kittitas County generally requires a separate permit for each regulated building or structure before construction, placement, alteration, repair, movement, conversion or demolition¹. Certain detached residential accessory structures of 200 square feet or less can be exempt when they are non-habitable and have no plumbing or mechanical systems, but an exempt structure must still meet setbacks and cannot sit in a floodway¹.

Kittitas County currently enforces the 2021 I-Codes with Washington State amendments¹¹. Permitted work ends with a final inspection before occupancy, and a new residence also requires a certificate of occupancy after required inspections and approvals^1,6. An owner may qualify for Washington's owner-builder contractor-registration exemption when working on their own property, but that exemption does not erase building, electrical, plumbing or septic requirements and does not cover work done to sell, demolish or lease the property⁸.

Kittitas County Community Development Services is the first stop for building permits, inspections, planning and zoning on unincorporated land². The office is at 411 N Ruby ST, Suite 2, Ellensburg WA 98926; call (509) 962-7506 or email cds@co.kittitas.wa.us². Completed building, planning and Fire Marshal applications and supporting documents can be uploaded through the county website².

Water availability and a Preliminary Site Analysis must be completed before a building-permit submittal¹¹. Published review estimates are 2 weeks for foundation-only review, 5 weeks for qualifying fast-track projects and 7 weeks for full review¹¹. County departments publish separate fee schedules: Community Development Services lists building and planning fees, Public Works lists its application fees, and Public Health lists on-site sewage fees¹². Ask each department for the current total for the project because charges vary by permit type, valuation and review method¹².

Unincorporated Kittitas County has zoning, with its official map maintained in county GIS; Ellensburg Urban Growth Area projects may also face joint city review and applicable city standards³. Inside Ellensburg, the city sets zoning; septic systems remain under Kittitas County Public Health^4,5.

Minimum lot size and setbacks depend on the zoning district; residential tables include 15-foot front and 20-foot rear setbacks, with exceptions³. Residential height is generally limited to 35 feet, with additional height possible for roofs pitched at least 4:12 and district or overlay exceptions³.

We could not confirm a universal minimum dwelling size; ask Community Development Services about the proposed home^2,7. Kittitas County recreational dry cabins must have 121–800 square feet of living space, with up to 200 additional square feet of attached garage or accessory area⁷. Dry cabins qualify only on remote sites without electrical power, as determined by the Building Official, and use is capped at 90 days annually⁷. Construction requires a permit including critical-areas approval, plus an Environmental Health permit for the required privy or composting toilet; factory-assembled structures are excluded⁷.

Kittitas County Public Health handles on-site sewage systems countywide; call 509-962-7515 or email environmentalhealth@co.kittitas.wa.us¹³. A Public Health environmental health specialist performs the parcel's site evaluation before design and installation permitting⁵. A licensed designer must prepare the design, although a homeowner may prepare one after the required pre-design meeting and may install the system⁵.

The installation permit lasts 1 year, and a 1-year renewal may be available if requested before expiration⁵. Public Health must inspect every installed system before final approval, and the drain field cannot be backfilled before that inspection⁵. Only about 1.9% of mapped soils are rated without severe limitations for a conventional septic drain field¹⁴. That statistic does not decide an individual parcel, so make the county site evaluation a purchase contingency before committing to a building location¹⁴.

In unincorporated Kittitas County, ordinary RV use is limited to 4 weeks out of any 6 weeks, subject to specified exceptions; the RV must remain licensed and highway-ready and disconnected from utilities when unused⁷. RV residence is allowed only under the primary-residence exception for manufactured/mobile-home communities existing before June 8, 2008⁷. Park models cannot be placed outside an established manufactured/mobile-home park unless permitted as a Special Care Dwelling, and require government-approved utilities during use⁷. Floodplain rules prohibit unattended RVs during flood season, November 15 through Memorial Day, and require road-ready units with quick-disconnect utilities¹⁵.

Tiny homes on wheels follow RV restrictions; stationary habitable structures with water or electricity under 200 square feet require building permits and must meet adopted-code room, fixture and life-safety standards⁷. Recreational dry cabins may be unheated, but propane- or oil-heated cabins must meet insulation requirements; sleeping lofts need code-compliant egress windows⁷. Wildland-Urban Interface requirements apply to dry cabins, with sprinkler exemptions requiring Fire Marshal approval⁷.

An ADU requires an administrative permit in an applicable zoning district, is limited to one per lot and 1,500 square feet, and cannot be a mobile home or RV³. County-road, right-of-way and county-parking-lot camping prohibitions address public property, with specified exceptions¹⁶.

1. Ask Community Development Services to identify the parcel's zoning district, overlays, setbacks and applicable building-permit path^2,3.
2. Establish water availability; a new well requires a Washington Department of Ecology permit, and the county monitors some wells for sealing, tagging and decommissioning⁹.
3. Obtain the Preliminary Site Analysis and complete the county septic site evaluation and design work before requesting an installation permit^5,11.
4. Apply to Public Works before creating new driveway access or working within a county right-of-way¹⁰.
5. If the site is in a flood hazard area, obtain a flood development permit before work begins¹⁵.
6. Submit the building application and related documents to Community Development Services, then follow the approved plans through required inspections^2,6.
7. Finish the septic and building inspections before occupancy and obtain the required certificate of occupancy for the new residence^1,5.

Start with parcel jurisdiction and zoning: incorporated municipalities may administer their own zoning, while county districts and overlays control standards on unincorporated land³. Confirm legal access early because Public Works approval is required before new driveway access or work in a county right-of-way¹⁰. A connection on a state-highway right-of-way instead requires written permission from the Washington Department of Transportation¹⁷.

Check flood mapping before choosing a building pad because development in an unincorporated flood hazard area requires a permit, and residential construction must be elevated 1 foot above base flood elevation¹⁵. Make septic feasibility a purchase contingency because only about 1.9% of mapped soils are rated without severe limitations for a conventional drain field¹⁴. Confirm the water source as well; a planned new well needs a Department of Ecology permit⁹. For a subdivision, utility lines serving and within it generally must be underground unless the county grants a waiver for impracticable site conditions¹⁸.