
Predesigned ADU plans to fast-track your build
Why use our plans to build your ADU?
Beautifully livable designs
Light, bright, and open proven floor plans with all the necessities for comfortable living, carefully designed, cost-effective to build, and sustainable and beautiful for years to come. We know these packages will streamline your build and result in a high quality living home.
Move-in sooner
Pre-designed plans typically save $15,000+ in additional design fees over custom designed ADUs and begin construction 6-9 months (or more) earlier.
Avoid pitfalls with Workbench expertise
We’re pre-development experts. We can be your guide on how to go from plans to completion and avoid many problems that could slow approval, increase costs, or worse, end in a finished build you don’t love.
A fit for most residential sites
Our designs come in a range of sizes to suit many lot sizes. We can guide you to the best way to take your goals and site pick the optimal plan. A few details about your site and a short conversation is typically what's needed to assess what can be built in your specific location.
Designed to be finished just the way you want
Unlike manufactured homes where options are limited to a few choices, our designs allow for you to finish the interiors to your taste and with the appliances and fixtures you want. Dimensions are kept as standard as possible so you have many styles and price points to choose from. We include finish planning guides and recommendations to help you make smart decisions without missing any details.
Options to fit your needs
Our plans our designed to allow you to mirror the these plans and in many cases alternates like sliding doors and skylights can be added. However, changes such as extending the unit’s measurements, adding or removing interior walls, or changing the number of rooms are considered custom designs and would incur additional time and cost.
Pre-designed may even be pre-approved
All our plan sets are designed to be approved in California. In some areas of California our pre-designed plans are also pre-approved by local planning departments allowing your project to skip the planning approval process and start constuction even faster.
We are working with many jurisdictions. If you are looking for pre-approved plans for your area please let us know. We’d be glad to help.
Avoid time-consuming phases and begin construction around 6 to 9 months sooner.
Pre-designed ADU plans starting at $3,500
What’s included in our designs?
Design Plans
Plans and elevations, materials, equipment, calculations all needed to acquire approval and building permits specific to your location.
Exterior Styling Guide
Thoughtfully chosen exterior styles and material guides allow you to match your ADU to your existing home style.
Interior Style & Planning Guides
All our plans come with a helpful interior finishes and appliance planning worksheet to help you and your builder coordinate whether you're DIYing it yourself or handing off the process entirely.
Featured Plans

MODEL WB625
WB625
Efficient, comfortable, light and bright. All the details for modern living carefully planned in 625 square feet.
Details
1 Bedroom | 1 Bathroom
625 sq ft | Footprint: 19’x35’
Recessed Entry w/ Covered Porch
Front Door / Back Door
Full Kitchen
Washer/Dryer
Built-In Storage
Full Bathroom
Central Living / Dining Space
One Bedroom with Closet
Square footage avoids increased permitting fees in most jurisdictions.
Flexible Exterior Styles
Our plans come with 3 roofline and exterior styles to fit your style.
California Modern
Beach Bungalow
Coastal Ranch

MODEL WB745
WB745
Flexible spaces and thoughtful storage and flow. All the details for modern living carefully planned in 745 square feet.
Details
1 Bedroom | 1 Bathroom + Flex Space/Den
745 sq ft | Footprint: 19’x35’
Recessed Entry w/ Covered Porch
Front Door / Back Door
Full Kitchen
Washer/Dryer
Built-In Storage
Full Bathroom
Central Living / Dining Space
One Bedroom with Closet
3 Flexible Exterior Styles
Flexible Exterior Styles
Our plans come with 3 roofline and exterior styles to fit your style.
California Modern
Beach Bungalow
Coastal Ranch
Get your build off to a great start.
To make sure we meet all the specifics of your build, we’ll need some details about your location and situation before preparing your pre-designed plans.
Typically we’ll respond with a few questions or schedule a brief call whichever you prefer. We’re glad to answer any questions you might have.
Enter Project details.
Answer a few site questions and determine best plans for your project.
Workbench prepares plans with your specifics.
Pay and download your pre-designed plan set and finish guides.
Developed in Santa Cruz
Workbench Built for good.
At Workbench we’re here to make an impact in California’s housing crisis. We’ve put our cumulative design/build experience into these plans and know they will valuable additions to your property and a pleasure to live in for years to come. Visit our main site to learn more about us and our services.