Dry Columbia Basin sagebrush steppe with basalt cliffs above a wide river and green irrigated vineyard rows at its edge.
Benton County, Washington Tri-Cities & Walla Walla

Barndominium Builders in Kennewick, Washington

Kennewick is one of the Tri-Cities, and most of it is built out in subdivisions, so a barndominium usually lands on one of the larger residential parcels or just past the limits on Benton County land. Inside the city, three offices shape the project: the Building Safety Division permits the house, the zoning code decides how big the lot must be and whether a horse can share it, and the Water Division supplies drinking water drawn from the Columbia River. Richland and Pasco run their own permit counters, so the parcel number matters more than the mailing address. We handle the whole path, from a custom plan sized to the setbacks through site preparation, the permit set and a turnkey build. Owners who want to raise the frame with their own crew can start from barndominium kits in steel or as pole barn homes instead. Kennewick publishes its own snow load and frost depth, so footings and roof framing are drawn to those numbers from the first sketch. Send the parcel through the survey and we will check the zone, the utility connections and whether the lot carries an irrigation assessment before anything is priced.

Kennewick at a glance

Principal county
Benton County
Building permit
City building department
Land use
City zoning, inside an urban growth area
Wastewater
Public sewer
Water
Public water system

Barndominium Kits and Pole Barn Homes in Kennewick

A kit suits an owner who wants to raise the shell with their own crew. A pole barn home sets its frame on posts and trusses (the engineering term is post-frame construction) and suits a wide, simple layout with a shop bay under the same roof; a metal building home uses a bolted steel frame. Which one fits your parcel comes down to the zoning, the site and the design values the local building office publishes, covered below.

Building a Barndominium in Kennewick: Permits, Zoning, Septic and Water

On rural land the zoning, septic and water answers often come before the building answer. Here is who decides each part in Kennewick, taken from the office or document that publishes it. Rules change, so check them again against your parcel before anything is drawn.

Who issues the building permit City building department

City of Kennewick Building Safety Division

Inside the city limits, Kennewick's Building Safety Division reviews plans and inspects new houses. A new single-family home can go over the counter, where the City says a complete submittal is usually turned around within 15 business days, or through an express option for new single-family homes that promises permits in two to three business days for a convenience fee. Land outside the limits is permitted by Benton County.

Source: 6.4 Residential Building Permits, City of Kennewick (go2kennewick.com)

Who decides the land use Inside an urban growth area

City of Kennewick Community Planning Department

Title 18 of the Kennewick Municipal Code gives every parcel in the city a zone with its own permitted uses and site standards. In the low-density RS zone the minimum lot is 8,000 square feet, and farm animals such as horses, cows and sheep are allowed only on lots of at least 30,000 square feet, at no more than one animal per half acre. Unincorporated land outside the city follows Benton County zoning instead.

Source: Chapter 18.12 Zone Districts and Standards, Kennewick Municipal Code (library.municode.com)

Sewer or septic Public sewer

City of Kennewick Utility Services Division; Benton-Franklin Health District off the sewer

Kennewick's Utility Services Division runs sewer collection and the wastewater treatment plant, which returns treated water to the Columbia River. City lots connect to that system. A parcel beyond the sewer needs an on-site septic permit from the Benton-Franklin Health District, the county health office for Benton County.

Source: Sewer/Wastewater, City of Kennewick (go2kennewick.com)

Where the water comes from Public water system

City of Kennewick Water Division

Kennewick's drinking water comes from the Columbia River and two Ranney collector wells beside it. The City's latest water quality report says the river treatment plant produced 42 percent of the water customers used in 2025 and the collector wells the other 58 percent. Land outside the city system usually means a private well, and the permit then needs evidence of an adequate water supply, often a well report.

Source: Water Quality Report (Consumer Confidence Report), City of Kennewick (go2kennewick.com)

Kennewick design criteria
The Building Safety Division's climatic and geographic design criteria (revised 17 September 2024) list a 20 psf roof and ground snow load, a 24-inch frost line depth, a 110 mph design wind speed and Seismic Design Category C, and require ice shield underlayment on roofs because of occasional severe conditions.

Source: Climatic and Geographic Design Criteria, City of Kennewick Building Safety Division (go2kennewick.com)

Kennewick Irrigation District
The Kennewick Irrigation District diverts Yakima River water at Prosser Dam and serves over 20,200 acres within a 55,000-acre boundary. Built for farms, it now serves mostly residential customers, and many lots in and around Kennewick carry its irrigation service and assessment.

Source: About KID, Kennewick Irrigation District (kid.org)

Building on land near Kennewick

Start with the zone: an 8,000 square foot RS lot takes a house, but a wide shop bay or a pole barn beside it needs one of the larger parcels, and animals need 30,000 square feet. The City's standard setback sheet also governs the shop: accessory buildings sit at least 5 feet from side and rear lines, 10 feet from existing structures, and a roll-up door wider than 6 feet facing the street pushes the front setback to 20 feet. Ask whether the lot has irrigation district water for landscaping, since that water is not for drinking. Plan footings to the 24-inch frost line. For genuine acreage, look at unincorporated ground on our Benton County page, where the county's rural zones and a private well change the checklist.

Other places in this part of Washington

Have land in or near Kennewick? Tell us about the parcel and what you want on it, and we will check it against the local rules before anything is drawn.

Building in Kennewick: questions

Start the survey
How much does it cost to build a barndominium in Kennewick?
The building is only part of the number. On a Kennewick lot the site work, the sewer and water connections, footings set to the 24-inch frost line and any irrigation district assessment all land in the budget, and the choice between a kit you assemble and a turnkey build moves it most of all. We price against the actual parcel rather than a flat rate. Our barndominium cost guide lays out sourced ranges and what pushes a build here up or down.
Do I need a building permit for a barndominium in Kennewick?
Yes. A barndominium you live in is a new single-family home, so inside the city it goes through the Building Safety Division's residential permit process, either over the counter or through the express option. If the parcel is outside the city limits, Benton County issues the permit, and Richland and Pasco each have their own offices. Send the parcel through the survey and we will confirm which one applies.
Can I keep horses and a shop on a Kennewick lot?
Only on the right lot. Kennewick's RS zone allows farm animals such as horses on lots of at least 30,000 square feet, with no more than one animal per half acre, and the shop must still meet the accessory-building setbacks. A combined house and shop under one roof often fits a lot better than two buildings, which is where our custom plans begin.
Does Kennewick land come with city water or a well?
Inside the city service area it is city water, treated from the Columbia River or drawn from collector wells beside it. Irrigation district water, where a lot has it, is raw river water for landscaping only. Outside the city system a home usually relies on a private well, and the building permit needs proof of an adequate water supply before it is issued.

Other places near Kennewick

Nearby places with their own pages. Across a city limit or a county line the permit office, the zoning, the septic program and the water rules can change, so each is covered separately.

Building in Kennewick?

Start with the survey. Tell us where the land is and what you want on it, and we will come back with which offices decide it, what the zoning allows, and a plan to fit.