Renton is a perfect place to build an ADU. Here are Renton's up-to-date ADU rules.

Understanding Renton, Washington's ADU rules and regulations for easy ADUs

Renton, Washington ADU Rules and Regulations | Cottage ADU

We're a team of architects, builders, and technologists committed to helping homeowners and pros build more and build better.

About Us | Cottage

Empower homeowners and pros to build more and build better.

Our mission

About Cottage

Room for more

We are owner-builders. Cottage is what we make it. We roll up our sleeves together, do whatever is required for our customers and business, and do it right.

Build like you own the place

In an opaque industry, we build trust with radical transparency. We offer this transparency. This commitment extends across our entire team, ensuring that every teammate, regardless of their role, is both a provider and recipient of clear, honest communication.

Transparency

We're taking an entirely new approach to an age-old industry. We aren't afraid to pave the path forward.

Breaking ground

We have an opportunity to remake the physical world we live in for the better. We operate with an optimism that there's no problem too hard for us to solve.

Optimistic leadership

Our core values

Cottage: Build your custom ADU in LA, San Diego, the Bay Area, and Seattle

Get competitive bids

We interview hundreds of Builders who operate in your neighborhood. Only 5% of Builders meet our standards.

Choose a general contractor to work with

We support you and your contractor to get your project across the finish line - on time, and on budget.

Build with the best

What makes a project eligible?

Upload your plans to Cottage

Already have plans? Get competitive bids from our trusted builders.

Bring your designs to life

Make room for more

The finished product

Join our team of architects, builders, and technologists in reimagining the residential construction industry.

Open positions

Join Our Team | Cottage

Perks & benefits

Build more, build better

Grow your business with Cottage's vetted clients and shovel-ready projects.

Build with Us

Tell us about your business, and we'll see if it's a good fit for us and your team.

Apply to join the Cottage Builder Network

We'll match you with high-intent clients in your service area.

Secure a project pipeline you can rely on

Cottage handles design & permitting, you build with exclusive tools to help manage your projects.

Focus on building

How it works

Are You a Contractor? Join Our Builder Network | Cottage

We set client expectations for project budget, timeline, and feasibility prior to introducing them to you.

Vetted Clients

We handle design development and permits while keeping you in the loop, allowing your team to focus on building.

We Design, You Build

We match you with a stream of qualified clients, as you manage in-progress construction.

Grow Your Business

We are proud to work with our network of quality builders to bring Cottage designs to life.

Why join the Cottage Builder Network?

Yes. Cottage specializes in designing custom Accessory Dwelling Units. Our company specializes in all types of custom ADUs: detached, garage conversions, and additions!

Do you only work on ADUs?

No! It is free to be part of the Cottage Builder Network and receive leads from Cottage.

Is there a cost to join?

<ul><li>We spend time learning everything we can about the homeowner’s expectations, project site, and unique conditions.</li><li>We learn the homeowner’s budget is adequate for the project they have in mind.</li><li>If a homeowner meets all of our criteria, we will move them forward to meet a contractor in our network.</li><li>We work with you to understand your company; we know where and how many projects you prefer to take on.</li>

What does Cottage do to qualify a project?

Fill out <a href='https://david045224.typeform.com/to/wRIAq1y9' target='_blank'>this form!</a> If your business works with ours, you’ll be building with Cottage in no time!

How do I get started?

What we look for

Work for yourself - from anywhere - on Cottage’s tech-forward architectural platform.

Are you an architect looking to <a href='https://start.cotta.ge/architect-partner-program' target='_blank'>get bids from the Cottage Builder Network?</a>

Design With Us

Tell us about your skills, experience, and goals to see if it's a fit.

Apply to Join

Onboard to our tech-first design platform and start working on projects at all stages.

Design with Cottage

We handle everything... so you can focus on building your client and architectural skill set.

Focus on Architecture

Are You an Architect/Designer? Join Our Design Studio | Cottage

We’ve worked with hundreds of homeowners on their custom ADU projects and have dozens of active construction projects at any given time. Our design process and standards are heavily informed by feedback from designers like you as we learn how to get better from every project we do together!

How many projects has Cottage done?

You’ll be the only designer on your projects - we trust your expertise and want you in the driver’s seat for design decisions! Our in-house architecture team is always available as a resource, and focuses on strategic initiatives for a better design process.

Will I be working on my projects with an in-house architect?

After submitting your application, process consists of two interviews. The first is a phone screen call with the Hiring Manager to discuss your experience and interest in Cottage. The second and final round is mock homeowner design call & portfolio review with two members of the Cottage team.

What does the interview process look like?

Yes. Your Cottage hours count towards NCARB AXP Requirements as A: Practice of Architecture. Our in-house Design Manager will sign off on your hours based on our standard hour distribution.

Does Cottage support AXP?

Yes, at no cost to you. Cottage equips all designers with a Cottage Google account and BIM 360/Revit, along with access to other software within our tech stack. Designers are responsible for providing their own computer.

Does Cottage provide software?

Yes. We want designers to celebrate the work they complete for Cottage homeowners.

Can I use Cottage work in my portfolio?

At this time, we are only able to work with US or Canadian residents with US citizenship or Visa eligibility to work as a freelancer.

Can international candidates apply?

Experienced, talented architectural designers

Looking for a fully-remote, fully-flexible work-for-yourself model

Tech-savvy and unafraid to challenge the industry status quo

Uncompromising in high quality output, and can hit this bar independently

Growth minded, looking to expand their business, skills and expertise

You run the meetings, you make the design decisions! Our process makes it easy for designers to work with homeowners.

Direct Homeowner Engagement

We’ve reimagined the residential design process with technology at the core. Spend more time on design and less time on busywork.

Design... Redesigned

See your projects go from schematic design to move-in ready in less than a year. Our platform is an unmatched opportunity for residential built work in your portfolio.

Designed to Build

The Design Studio is at the heart of every happy homeowner’s story. Great design is what brings Cottage projects to life.

Why join the Cottage Design Studio?

Featured, recently built ADUs including flex space, in-law unit, detached, rental income generating, office and hobby spaces.

Featured Cottage ADUs | Cottage

Featured ADU Projects by Cottage

Timeless, with a harmonious blend of ornate details and luxurious finishes for an elegant atmosphere.

Warm, earthy tones combining natural textures with rustic accents, for a serene ambiance.

Sleek and minimalist, borrows from European aesthetics for an uncluttered look.

Top-of-the-line finishes and appliances that elevate the look and feel of the interior space.

A smart mix of trusted finishes and appliances to curate a comfortable ambiance without blowing the budget.

From your bathroom tile to your kitchen cabinets, interior finishes give your ADU a distinct style and feel. Choose one of our curated finish packages as a starting point, or consult with a Cottage Designer to add an extra level of customization.

Interior Finish Packages

Design your custom ADU floor plan online and see a starting price.

Choosing your floor plan is simply a starting point to help guide our initial conversation. There will be plenty of opportunities to customize your layout, move around windows and doors, select your finishes, or even change your mind entirely.

It all starts with your floor plan

{bed} Bed | {bath} Bath | {size} sq. ft. ADU Floor Plan - {name} | Cottage

Price

Rooms

Shape

Size

ADU Floor Plans | Cottage

ADU Floor Plans

It all starts with a floor plan. Select from dozens of Cottage-designed plans as the jumping off point for your custom ADU.

Choose a floor plan

From fine-tuning the layout, to selecting materials, to adding your must-have features, you’ll work with your designer to tailor your ADU design.

Customize your design

We provide a curated list of finishes and appliances for you to customize the interior of your ADU. You’ll have plenty of options to choose from to meet your design and budget goals.

Select your finishes 

 Your property, budget, and design preferences are unique – so your ADU should be, too. You’ll work with a dedicated Cottage designer who will craft a custom architectural plan that checks all your boxes.

Custom Designed Just For You

Homeowners choose Cottage for their ADU. Get a trusted ADU contractor, custom design, zero-hassle process, and the best value ADU in Los Angeles, San Diego, San Francisco Bay Area, and Seattle.

Jumpstart the design process with a floor plan from our catalog of proven designs. Varying in size, shape, and layout, each blends space efficiency and comfort. You’ll be able to customize your design to achieve exactly what you want.

Find Your Floor Plan

Subtitle

Custom ADUs Made Simple

ADUs Made Simple

Seattle's New Way to ADU

With your exact location and project details in mind, we match you with a vetted contractor to take on your project. They’ll have extensive experience building near you, which means they know the finer points of ADU construction in your neighborhood.

Cottage: Custom ADUs in LA, San Diego, Bay Area, & Seattle

Cottage: Custom ADUs in the Bay Area

Cottage: Custom ADUs in Los Angeles

Cottage: Custom ADUs in San Diego

Cottage: Custom ADUs in Seattle

Discover what type of ADU is best suited for your property, goals, and budget.

Feasibility

Work with a Cottage Designer to develop custom architectural plans and select finishes for your ADU.

Design

We prepare your permit application and work directly with the city to expedite your permits.

Permitting

We pair you with a pre-vetted General Contractor and work together to bring your ADU plans to life.

Construction

We guide you through design, permitting, and construction with a vetted contractor. You get to be involved in the fun parts of design, while we handle the paperwork and heavy lifting.

Hassle-Free Process

100+ completed ADUs and counting

Already have a set of plans?

Attached ADU for Kathy’s aging parents

Backyard home for Rebeca’s son, Adrian

Detached ADU for Bob’s daughter

Backyard cottage for Jocelyn to age in place

We rigorously vet builders for quality, service, and value. We accept just 5% of contractor applicants.

Vetted contractors

Get multiple line-item bids, months earlier than working with an architect.

Multiple competitive bids

We track how contractors perform on timeline and budget. You get treated like a repeat customer.

Contractor performance tracking

Fair pricing from top contractors

Ready to get started?

We’ve reimagined the experience of building a custom ADU to save you time and money.

Design and build the smart way

Connect with vetted pros who have designed and built in your neighborhood. Local expertise saves you time and hassle. 

Local ADU Experts

Partner with a dedicated Designer to create a custom ADU that checks all your boxes.

Work 1:1 with a Designer

Visualize your ADU through 3D renderings, and fine-tune the details to land on the perfect design.

Design in 3D

Customize your interiors by choosing from our list of hand-picked finishes and appliances. 

Select from curated finishes

Modern design experience

From detached ADUs, to JADUs, to garage conversions, we’ve completed projects of all sizes and styles.

From garage conversions, to detached ADUs, to JADUs, we’ve completed projects of all sizes and styles.

From DADUs, to attached ADUs, to garage conversions, we’ve completed projects of all sizes and styles.

150+ completed projects

Understand what’s possible on your property and get budget guidance.

Design your custom ADU, then receive multiple bids for the build.

Design & Bid

Sit back as we handle documentation, engineering and permitting.

We support you and your contractor to get your project across the finish line.

Streamlined process

What our homeowners say

What our Bay Area homeowners say

What our LA homeowners say

What our SD homeowners say

What our Seattle homeowners say

At no cost to you, we scope the details up front to keep your project within budget

We've surveyed the market and negotiated competitive contractor pricing for you

We design for both elegance and efficiency, keeping build costs down

Best-in-Market Value

We rigorously review contractors for quality, communication, and pricing that's competitive in the market. You save the time and effort needed to vet builders yourself.

Vetted by industry experts

We've surveyed hundreds of contractors, and only 5% of applicants have met the quality standards we require to join our builder network. You’ll get a beautiful, well-constructed ADU within budget and on-time.

Best-in-class in your local market

All General Contractors hold an active contractor's license in good standing, Contractor's Bond, Commercial General liability insurance of $1 million, Worker's Compensation and Employer's Liability insurance of $1 million.

Licensed, bonded, and insured

Are you a contractor looking to <a href='/contractors' style='color: white'>partner with Cottage</a>?

We'll pair you with a trusted builder from our network. Each contractor is fully qualified, vetted, and ready to build your ADU.

We'll pair you with a licensed builder from our trusted network in the Bay Area. Each contractor is fully qualified, vetted, and ready to build your ADU.

We'll pair you with a licensed builder from our trusted network in Los Angeles. Each contractor is fully qualified, vetted, and ready to build your ADU.

Renton, Washington

Renton

Zoning

Number of units

Building size

Setbacks

Parking

Owner-occupancy

Want to learn more about ADU regulations in your area?