{"id":30144,"date":"2026-08-09T14:32:33","date_gmt":"2026-08-09T14:32:33","guid":{"rendered":"https:\/\/ark7.com\/blog\/?p=30144"},"modified":"2026-08-09T14:32:35","modified_gmt":"2026-08-09T14:32:35","slug":"adu-builders-washington","status":"publish","type":"post","link":"https:\/\/ark7.com\/blog\/learn\/cities\/adu-builders-washington\/","title":{"rendered":"10 Best ADU Builders in Washington &#8211; 2026"},"content":{"rendered":"\n<p>Washington\u2019s ADU rules are broad at the state level, but their practical effect depends heavily on location. In many cities and counties planning under the Growth Management Act, qualifying residential lots within urban growth areas may support up to two accessory dwelling units. That does not mean every property receives the same treatment, however. Jurisdictional planning status and the exact location of a parcel can determine which standards apply, so homeowners in nearby areas may encounter very different requirements.<\/p>\n\n\n\n<p>For those who want residential real estate exposure without managing an ADU project,<a href=\"https:\/\/ark7.com\/\"> Ark7<\/a> provides fractional interests in professionally managed rental-property series. Certain shares may start at $20, subject to offering availability and investor eligibility.<\/p>\n\n\n\n<p>This guide examines 10 ADU builders working across Washington, drawing on publicly available company information, advertised pricing, service descriptions, and project portfolios reviewed in 2026. Because many project totals and cost estimates come directly from the companies themselves, verify contractor licensing through Washington Labor &amp; Industries and confirm current pricing and project details before signing a contract.<\/p>\n\n\n\n<div class=\"bg-blue-grey-1 padding-32px border-radius-12px margin-20px-t margin-20px-b\">\t \n  <div class=\"bg-white text-center padding-20px-v border-radius-8px\">\t \n    <h3 class=\"margin-auto display-block\">New to passive real estate investing?<\/h3>\t \n    <a class=\"margin-auto a7-button\" href=\"https:\/\/ark7.com\/?tc=K8L9N\" target=\"_blank\" rel=\"noopener\">Explore Ark7 Opportunities<\/a>\t \n  <\/div>\t \n<\/div>\n<div class=\"ark7-property-list padding-20px-v margin-20px-t margin-20px-b\" data-tags=\"SEOWidgetFeatured\" data-tc=\"K8L9N\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Key Takeaways<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Washington law requires many cities and counties planning under the Growth Management Act to allow up to two ADUs on qualifying residential lots within urban growth areas, subject to local and site-specific requirements.<\/li>\n\n\n\n<li>HB 1337 took effect July 23, 2023, with local implementation requirements tied to jurisdictions&#8217; periodic Growth Management Act updates.<\/li>\n\n\n\n<li>Covered jurisdictions generally may not impose an owner-occupancy requirement, subject to exceptions such as certain short-term rentals and applicable local rules.<\/li>\n\n\n\n<li>Washington law can permit ADUs to be sold independently of the principal unit in applicable jurisdictions.<\/li>\n\n\n\n<li>Published builder pricing runs from a $119,900 starting plan price to more than $600,000 for custom detached units. Starting prices typically exclude site work, utilities, and permits.<\/li>\n\n\n\n<li>For 2026, Seattle SDCI applied a 6.5% inflationary increase to most fees, while construction and master-use permit fees increased 18% year over year.<\/li>\n\n\n\n<li><a href=\"https:\/\/ark7.com\/\">Ark7<\/a> offers shares in certain rental-property series starting as low as $20, subject to offering availability and eligibility.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>How This List Was Compiled<\/strong><\/h2>\n\n\n\n<p>This list was assembled from publicly available company information rather than a scoring model, and no ranking is implied by the order below. Companies were compared on ADU-specific experience, cost transparency, service breadth, publicly visible credentials, and market differentiation. Project counts, pricing, and experience figures are company-reported and labeled as such throughout. Verify contractor registration, bond, and insurance directly through Washington Labor &amp; Industries using the exact legal business name before contracting.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Washington ADU Rules to Understand First<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Who is covered<\/strong>: Many cities and counties fully planning under the Growth Management Act must allow up to two ADUs on residential lots that permit single-family homes, within urban growth areas. Local requirements still vary by jurisdiction and site.<\/li>\n\n\n\n<li><strong>When it took effect<\/strong>: HB 1337 took effect July 23, 2023. Local governments had implementation deadlines tied to their periodic comprehensive-plan updates, which is why adoption happened at different times across the state.<\/li>\n\n\n\n<li><strong>Owner-occupancy<\/strong>: In covered jurisdictions, owner-occupancy generally may not be required, though exceptions apply, including where the ADU is used as a short-term rental.<\/li>\n\n\n\n<li><strong>Separate ownership<\/strong>: Washington law can permit ADUs to be sold independently of the principal unit in applicable jurisdictions.<\/li>\n\n\n\n<li><strong>Preapproved plans<\/strong>: Some jurisdictions use tools such as expedited review, consolidated permits, preapproved plans, or modified development charges. Programs vary considerably and change.<\/li>\n\n\n\n<li><strong>Value expectations<\/strong>: An ADU may increase a property&#8217;s value, but the effect varies substantially by location, size, design, rental potential, and market conditions.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>10 ADU Companies Operating in Washington for 2026<\/strong><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>1. Giant Builders (Published Cost Breakdowns)<\/strong><\/h3>\n\n\n\n<p><strong>Service Area:<\/strong> Seattle metro area<\/p>\n\n\n\n<p><strong>Type:<\/strong> Design-Build<\/p>\n\n\n\n<p><strong>Pricing:<\/strong> Company-published estimates of roughly $257,985 to $275,184 for standard DADUs<\/p>\n\n\n\n<p><strong>Project Count:<\/strong> More than 100 completed ADU projects, per company materials<\/p>\n\n\n\n<p>Giant Builders advertises costs it says run 20% to 25% below market averages. We could not independently verify that comparison, since it depends on comparable scopes, specifications, square footage, and geography.<\/p>\n\n\n\n<p><strong>What Sets Giant Builders Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Free online ADU cost calculator<\/li>\n\n\n\n<li>Permit handling for Seattle SDCI and King County<\/li>\n\n\n\n<li>Company-stated five-year warranty on construction work<\/li>\n\n\n\n<li>Note that the company&#8217;s calculator states an incorrect HB 1337 effective date of July 2025; the law took effect July 23, 2023<\/li>\n\n\n\n<li>Verify the exact legal business name, contractor registration, bond, and insurance directly through Washington L&amp;I, as we were unable to confirm the registration number published on its website<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>2. Puget Sound ADU Builders (Condoization Services)<\/strong><\/h3>\n\n\n\n<p><strong>Location:<\/strong> 2226 Eastlake Ave E, Seattle, WA 98102<\/p>\n\n\n\n<p><strong>Type:<\/strong> Full-Service Design-Build<\/p>\n\n\n\n<p><strong>Experience:<\/strong> Company states more than 25 years of design and ADU construction experience<\/p>\n\n\n\n<p><strong>Ownership:<\/strong> Women-owned<\/p>\n\n\n\n<p>The company offers condoization services intended to help qualifying properties establish separately owned units, subject to applicable local, title, and condominium requirements. Separate sale is a legal and planning process rather than something automatically available.<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Full service from feasibility assessment through construction completion<\/li>\n\n\n\n<li>Custom architectural and interior design services included<\/li>\n\n\n\n<li>Certifications including ADA-compliant, NAHB, and Master Builders Association<\/li>\n\n\n\n<li>Financing guidance across HELOC, construction loans, and cash-out refinance<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>3. CAST Architecture (Preapproved Cedar Cottage)<\/strong><\/h3>\n\n\n\n<p><strong>Location:<\/strong> 115 North 36th Street, Seattle, WA 98103<\/p>\n\n\n\n<p><strong>Type:<\/strong> Architecture Firm<\/p>\n\n\n\n<p><strong>Portfolio:<\/strong> Company says it has designed more than 80 backyard cottages and ADUs<\/p>\n\n\n\n<p>CAST&#8217;s Cedar Cottage model is pre-approved in Seattle and Kirkland, which can reduce approval timelines. Award-recognized designs include the Widner Cottage and Lichtenstein Studio.<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>In-house architect on every project<\/li>\n\n\n\n<li>Pre-approved plans that expedite Seattle and Kirkland permitting<\/li>\n\n\n\n<li>Award-recognized portfolio<\/li>\n\n\n\n<li>Specialization in backyard cottage design<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>4. Cascadia ADU (Four-County Coverage)<\/strong><\/h3>\n\n\n\n<p><strong>Location:<\/strong> 901 1st Street, Snohomish, WA 98290<\/p>\n\n\n\n<p><strong>Type:<\/strong> Design-Build<\/p>\n\n\n\n<p><strong>Service Area:<\/strong> King, Snohomish, Skagit, and Chelan counties<\/p>\n\n\n\n<p><strong>Experience:<\/strong> Company states its ADU work began more than 10 years ago<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Multi-county service area providing flexibility north of Seattle<\/li>\n\n\n\n<li>Full-service design, permitting, and construction<\/li>\n\n\n\n<li>Eco-friendly building practices<\/li>\n\n\n\n<li>A third-party directory reports an 8 to 10 week figure for this company, but that does not appear on its current primary website and would describe a construction phase rather than total duration. Ask for a documented end-to-end schedule.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>5. Coates Design Architects (Sustainable Architecture)<\/strong><\/h3>\n\n\n\n<p><strong>Location:<\/strong> 900 Winslow Way East, Bainbridge Island, WA 98110<\/p>\n\n\n\n<p><strong>Type:<\/strong> Architecture Firm<\/p>\n\n\n\n<p><strong>Pricing and Timeline:<\/strong> Request current figures directly<\/p>\n\n\n\n<p>Based on Bainbridge Island, Coates Design works on ADUs with an emphasis on sustainable architecture, including a documented Bainbridge Island ADU project.<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Eco-friendly and sustainable design expertise<\/li>\n\n\n\n<li>Full architectural services from concept through construction<\/li>\n\n\n\n<li>Experience across ADU types<\/li>\n\n\n\n<li>Timeline and project cost figures circulating on third-party directories were not substantiated by the company&#8217;s own materials<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>6. True Built Home (Lowest Published Entry Price)<\/strong><\/h3>\n\n\n\n<p><strong>Location:<\/strong> 3403 North Proctor Street, Tacoma, WA 98407<\/p>\n\n\n\n<p><strong>Type:<\/strong> Plan-Based Builder<\/p>\n\n\n\n<p><strong>Starting Price:<\/strong> Chehalis ADU plan starting at $119,900<\/p>\n\n\n\n<p><strong>Service Area:<\/strong> Washington and Oregon<\/p>\n\n\n\n<p>Homeowners should verify what site work, utilities, permits, land preparation, and jurisdiction-specific costs are excluded, since a starting plan price is not equivalent to an all-in project cost.<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Lowest published starting price identified in this review<\/li>\n\n\n\n<li>Multiple customizable pre-designed floor plans<\/li>\n\n\n\n<li>Predictable, published pricing model<\/li>\n\n\n\n<li>Dual-state coverage across Washington and Oregon<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>7. Chapman Projects (Long Operating History)<\/strong><\/h3>\n\n\n\n<p><strong>Location:<\/strong> 4225 335th Place Southeast, Fall City, WA 98024<\/p>\n\n\n\n<p><strong>Type:<\/strong> General Contractor<\/p>\n\n\n\n<p><strong>Experience:<\/strong> Company reports more than 20 years in business<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Two decades of construction experience<\/li>\n\n\n\n<li>Eco-friendly building practices<\/li>\n\n\n\n<li>Serves broader King County beyond Seattle proper<\/li>\n\n\n\n<li>Professional references from design partners<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>8. Ballard Backyard Cottages (Seattle Specialist)<\/strong><\/h3>\n\n\n\n<p><strong>Location:<\/strong> 4142 2nd Avenue Northwest, Seattle, WA 98107<\/p>\n\n\n\n<p><strong>Type:<\/strong> DADU Specialist<\/p>\n\n\n\n<p>Ballard Backyard Cottages advertises full-service DADU and ADU design, permitting, and construction focused on the Seattle market.<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Central Seattle location and local permitting knowledge<\/li>\n\n\n\n<li>Custom builds, conversions, and prefab cabin options<\/li>\n\n\n\n<li>Guidance through the permitting process<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>9. Tenhulzen Remodeling (Eastside Coverage)<\/strong><\/h3>\n\n\n\n<p><strong>Service Area:<\/strong> Woodinville and Seattle&#8217;s Greater Eastside<\/p>\n\n\n\n<p><strong>Type:<\/strong> Design-Build<\/p>\n\n\n\n<p><strong>Locations:<\/strong> 14701 148th Ave NE and 17280 Woodinville Redmond Rd NE, Woodinville, WA<\/p>\n\n\n\n<p>Formerly Tenhulzen Residential, the company rebranded to Tenhulzen Remodeling. It offers both pre-approved plans for speed and custom designs for personalization.<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Dual approach: pre-approved plans or full custom designs<\/li>\n\n\n\n<li>Accommodates a range of budget levels<\/li>\n\n\n\n<li>Established Eastside presence<\/li>\n\n\n\n<li>Focus on added property value<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>10. Seattle ADU Builders (Published Price Points)<\/strong><\/h3>\n\n\n\n<p><strong>Service Area:<\/strong> Seattle and King County<\/p>\n\n\n\n<p><strong>Type:<\/strong> Full-Service ADU Contractor<\/p>\n\n\n\n<p><strong>Pricing:<\/strong> Starting around $450,000 for detached ADUs, $300,000 for attached ADUs, and $200,000 for garage conversions<\/p>\n\n\n\n<p><strong>What Sets It Apart:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Licensed contractor with published price points<\/li>\n\n\n\n<li>Seattle and King County specialization<\/li>\n\n\n\n<li>Full design-build capability across all three ADU types<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>How to Choose the Right ADU Builder<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>By whether you need an architect or a contractor<\/strong>: CAST and Coates Design are architecture firms delivering design and permitting; the remainder deliver construction, with several offering both.<\/li>\n\n\n\n<li><strong>By published price transparency<\/strong>: True Built Home and Seattle ADU Builders publish starting figures, Giant Builders publishes a calculator, and several others quote only on request.<\/li>\n\n\n\n<li><strong>By region<\/strong>: Seattle proper is served by Puget Sound ADU Builders, CAST, Ballard, and Seattle ADU Builders; the Eastside by Tenhulzen; north Puget Sound by Cascadia; the South Sound by True Built Home; Bainbridge and the peninsula by Coates; and outer King County by Chapman.<\/li>\n\n\n\n<li><strong>By preapproved plan access<\/strong>: CAST&#8217;s Cedar Cottage is pre-approved in Seattle and Kirkland, and Tenhulzen offers pre-approved plan options, which can shorten review where the program applies.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Questions to Ask Any Washington ADU Builder<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Does my jurisdiction plan under the Growth Management Act, and is my parcel inside an urban growth area?<\/li>\n\n\n\n<li>Is your Washington L&amp;I contractor registration active under your exact legal business name, with current bond and insurance?<\/li>\n\n\n\n<li>Are your published project counts company-reported or independently verifiable?<\/li>\n\n\n\n<li>Does your quoted timeline cover the construction phase only or design through final inspection?<\/li>\n\n\n\n<li>What does a published starting price exclude?<\/li>\n\n\n\n<li>What warranty do you provide, and how long does it run after completion?<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Financing an ADU in Washington<\/strong><\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Home equity options<\/strong>: HELOCs are the most common route, using existing home equity with interest-only payments on amounts drawn.<\/li>\n\n\n\n<li><strong>Construction lending<\/strong>: Construction loans convert to permanent financing upon completion.<\/li>\n\n\n\n<li><strong>Personal loans<\/strong>: Suitable for smaller conversion projects where equity is limited.<\/li>\n\n\n\n<li><strong>Cash investment<\/strong>: Eliminates interest costs but ties up capital.<\/li>\n\n\n\n<li><strong>Permit fee planning<\/strong>: For 2026, Seattle SDCI applied a 6.5% inflationary increase to most fees, while construction permit and master use permit fees increased 18% year over year. One Seattle-area builder estimates typical permit costs of $20,000 to $40,000 depending on scope, which is a builder estimate rather than an official city fee range.<\/li>\n\n\n\n<li><strong>Cost benchmarks<\/strong>: Builder-published estimates place new detached ADUs at $300,000 to $600,000 and above, attached ADUs at $200,000 to $400,000, garage conversions at $80,000 to $250,000, and basement conversions at $100,000 to $350,000, with new DADU construction commonly cited at $400 to $650 per square foot.<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Comparing ADUs and Fractional Real Estate<\/strong><\/h2>\n\n\n\n<p>Building an ADU is a hands-on approach that requires significant upfront capital, construction management, and ongoing landlord responsibilities. Rental-market conditions also vary considerably across Washington.<\/p>\n\n\n\n<p><strong>ADU considerations:<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Some builders estimate that certain Seattle DADUs may rent for roughly $1,500 to $3,500 per month depending on size and neighborhood, and one builder estimates a 6 to 12 year payback for some projects. These are marketing figures rather than independent benchmarks.<\/li>\n\n\n\n<li>Actual payback varies considerably with project cost, rent, financing, vacancy, taxes, insurance, maintenance, and management.<\/li>\n\n\n\n<li>An ADU may increase a property&#8217;s value, but the effect varies substantially and should be confirmed with a local appraiser rather than assumed.<\/li>\n\n\n\n<li>Evaluate local rents, vacancy, expenses, and financing for your specific area rather than relying on statewide figures.<\/li>\n\n\n\n<li>Any rent-to-cost figure should be stated as an illustrative gross estimate, calculated as annual rent divided by total project cost before expenses, not as a return on investment.<\/li>\n<\/ul>\n\n\n\n<p><strong>How fractional investing compares:<\/strong><\/p>\n\n\n\n<p>For those who prefer fractional real estate exposure rather than developing and managing an ADU directly,<a href=\"https:\/\/ark7.com\/\"> Ark7<\/a> is another model to consider:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Shares in certain rental-property series starting as low as $20 per share, subject to offering availability and eligibility<\/li>\n\n\n\n<li>Eligible properties may make monthly cash distributions when available, subject to property performance, expenses, reserves, and offering terms<\/li>\n\n\n\n<li>Professional property selection and management<\/li>\n\n\n\n<li>Exposure across multiple markets rather than a single local property<\/li>\n\n\n\n<li>No construction timelines or permitting to manage<\/li>\n\n\n\n<li>Potential access to secondary trading, subject to holding periods, legal and state restrictions, platform availability, and market liquidity. Liquidity is not guaranteed.<\/li>\n\n\n\n<li><a href=\"https:\/\/ark7.com\/ira\">Ark7 IRA options<\/a> support Traditional and Roth accounts, subject to IRA rules, custodian fees, and individual circumstances<\/li>\n<\/ul>\n\n\n\n<p>Returns and distributions are not guaranteed, and these are speculative securities involving substantial risk, including illiquidity, lack of diversification, and complete loss of capital.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Conclusion<\/strong><\/h2>\n\n\n\n<p>Washington&#8217;s ADU rules have opened real capacity in many jurisdictions, but the state framework applies through local implementation rather than uniformly. What your parcel allows depends on whether your jurisdiction plans under the Growth Management Act, whether you sit inside an urban growth area, and what local standards your city or county has adopted.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Why Washington Stands Out for ADU Projects<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>State-level framework<\/strong>: Many GMA-planning jurisdictions must allow up to two ADUs on qualifying residential lots within urban growth areas.<\/li>\n\n\n\n<li><strong>Limited owner-occupancy mandates<\/strong>: Covered jurisdictions generally may not require owner occupancy, subject to short-term rental and local exceptions.<\/li>\n\n\n\n<li><strong>Separate ownership pathway<\/strong>: Washington law can permit ADUs to be sold independently of the principal unit in applicable jurisdictions.<\/li>\n\n\n\n<li><strong>Pre-approved plan programs<\/strong>: Some jurisdictions offer permit-ready plans that can streamline review.<\/li>\n\n\n\n<li><strong>Deep builder market<\/strong>: Architecture-led firms, design-build contractors, and plan-based builders all compete locally.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Investor Tips for Washington ADU Projects<\/strong><\/h3>\n\n\n\n<p>Confirm with your city or county planning department what applies to your specific parcel before commissioning design, since the state framework reaches jurisdictions differently. Verify contractor registration, bond, and insurance directly through Labor &amp; Industries using the exact legal business name, and treat a license number printed on a company website as a starting point rather than proof. Ask what a published starting price excludes, because site work, utilities, and permits frequently sit outside it. When modeling returns, separate gross rent from net income and build projections from current comparable listings in your neighborhood rather than statewide ranges.<\/p>\n\n\n\n<p>For those who prefer residential real estate exposure without a construction project,<a href=\"https:\/\/ark7.com\/\"> Ark7<\/a> offers shares in rental-property series starting at $20, subject to offering availability and eligibility.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Frequently Asked Questions<\/strong><\/h2>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Does Washington&#8217;s two-ADU rule apply to my property?<\/strong><\/h3>\n\n\n\n<p>Not automatically. Washington law requires many cities and counties planning under the Growth Management Act to allow up to two ADUs on qualifying residential lots within urban growth areas, subject to local and site-specific requirements. Whether your parcel is covered depends on your jurisdiction&#8217;s planning status and whether the property sits inside an urban growth area. Confirm with your local planning department rather than assuming statewide application.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>When did the current rules actually take effect?<\/strong><\/h3>\n\n\n\n<p>HB 1337 took effect July 23, 2023. Local governments had implementation deadlines tied to their periodic comprehensive-plan updates, which is why adoption happened at different times across the state and why some builder materials cite different dates. If a company&#8217;s published summary gives a different effective date, treat its other regulatory claims with corresponding caution.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Can I be required to live on the property?<\/strong><\/h3>\n\n\n\n<p>In covered jurisdictions, owner-occupancy generally may not be required. Exceptions apply, including where the ADU is used as a short-term rental, and rural or non-covered properties may operate under different local rules. Confirm your jurisdiction&#8217;s current requirements before planning around a rental strategy that assumes you will live elsewhere.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>How do I verify a Washington contractor before hiring?<\/strong><\/h3>\n\n\n\n<p>Search the Washington Labor &amp; Industries contractor database using the exact legal business name, not just a trade name or a number printed on a website. Confirm active registration status, current bond, and liability coverage, and note the date you checked. Similar business names and registration numbers can produce misleading search results, so match the entity carefully before signing anything.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>Are there incentives or grants for building an ADU in Washington?<\/strong><\/h3>\n\n\n\n<p>Some jurisdictions use tools such as expedited review, consolidated permits, preapproved plans, or modified development charges. Programs vary considerably by city and county and change over time, so check directly with your local planning department rather than assuming an incentive applies. Many homeowners finance construction through HELOCs, cash-out refinances, or construction loans, with rates and eligibility varying by borrower.<\/p>\n\n\n\n<p><em>Neither Ark7 nor Ark7 Properties is a broker-dealer or an investment adviser. Dalmore Group LLC, a registered broker-dealer and member FINRA\/SIPC, located at 525 Green Place, Woodmere, NY 11598, is the broker-dealer of record for Ark7, an issuer direct offering. Neither Ark7 nor Dalmore makes recommendations or provides advice about investments, and nothing here should be construed as a recommendation for any security. An investment in an offering constitutes an investment in a particular series and not in Ark7 or any of the underlying assets. Investments on the Ark7 platform are speculative and involve substantial risks, including illiquidity, lack of diversification, and complete loss of capital. Cash distributions are not guaranteed and are subject to property performance, expenses, reserves, and offering terms. Past performance is no guarantee of future results. This article is for informational purposes only.<\/em><\/p>\n\n\n\n<div class=\"bg-blue-grey-1 padding-32px border-radius-12px margin-20px-t margin-20px-b\">\t \n  <div class=\"bg-white text-center padding-20px-v border-radius-8px\">\t \n    <h3 class=\"margin-auto display-block\">New to passive real estate investing?<\/h3>\t \n    <a class=\"margin-auto a7-button\" href=\"https:\/\/ark7.com\/?tc=K8L9N\" target=\"_blank\" rel=\"noopener\">Explore Ark7 Opportunities<\/a>\t \n  <\/div>\t \n<\/div>\n<div class=\"ark7-property-list padding-20px-v margin-20px-t margin-20px-b\" data-tags=\"SEOWidgetFeatured\" data-tc=\"K8L9N\"><\/div>\n","protected":false},"excerpt":{"rendered":"<p>Washington\u2019s ADU rules are broad at the state level, but their practical effect depends heavily on location. In many cities and counties planning under the Growth Management Act, qualifying residential lots within urban growth areas may support up to two accessory dwelling units. That does not mean every property receives the same treatment, however. Jurisdictional &hellip;<\/p>\n<p class=\"read-more\"> <a class=\"\" href=\"https:\/\/ark7.com\/blog\/learn\/cities\/adu-builders-washington\/\"> <span class=\"screen-reader-text\">10 Best ADU Builders in Washington &#8211; 2026<\/span> Read More \u00bb<\/a><\/p>\n","protected":false},"author":22,"featured_media":3369,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_mi_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[167],"tags":[],"class_list":["post-30144","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cities"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v21.5 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>10 Best ADU Builders in Washington - 2026 - Ark7<\/title>\n<meta name=\"description\" content=\"Discover the 10 best ADU builders in Washington for 2026. 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