Â
Â
If you want a backyard home under 800 square feet, three United Signature plans cover the main choices: the Main St ADU at 550 square feet with one bedroom, the Country Cottage at 785 square feet with two bedrooms, and Cedar Groove at 800 square feet with two bedrooms and a dedicated laundry room. The right one depends on who will live there, how much yard you want to keep, and whether you need a second bedroom or simply a well-planned single-bedroom home.
All three are detached, single-story units, which keeps them easy to live in, simpler to permit than taller designs, and comfortable for older residents. Each plan has its own page in the ADU plan collection with drawings and current pricing. This article compares them side by side so you can narrow the list before you look at the details.
Â
The Three Plans at a Glance
Main St ADU, 550 square feet: one bedroom with a walk-in closet, open living and kitchen area, pantry with stacked laundry, simple gable roof.
The Country Cottage, 785 square feet: two bedrooms placed on opposite ends of the home, open great room, full bathroom with tub and shower, classic cottage exterior.
Cedar Groove, 800 square feet: two bedrooms, open great room with an island kitchen and dining area, separate laundry room, mechanical space, front porch and rear patio. Also available in a version with a garage.
Main St ADU: The Most Home in the Smallest Footprint
The Main St ADU is built around one idea: a single bedroom that feels like a real bedroom, not a sleeping alcove. The living area and kitchen share one bright open space, and storage is designed into the plan from the start instead of being squeezed in later. A walk-in closet and a pantry that also holds a stacked washer and dryer keep everyday items out of the main room.
Who the Main St Plan Fits Best
A single occupant or a couple, a long-term rental aimed at one or two tenants, or a parent who wants independence close to family without maintaining a larger home. It is also the plan most likely to fit on a smaller lot or alongside a large existing house, where floor area and lot coverage limits leave less room.
What to Keep in Mind
One bedroom limits flexibility. If you might need a guest room, a home office or space for a caregiver later, compare it carefully with the two-bedroom plans before deciding.
Â
The Country Cottage: Two Private Bedrooms in a Classic Shape
The Country Cottage adds a second bedroom without making the home feel like a corridor of doors. The two bedrooms sit on opposite sides of the central great room, so each has its own quiet end of the house. That arrangement works especially well for two adults sharing the unit, such as roommates, a parent with a live-in helper, or a couple who each want a separate room for sleep or work.
The exterior is deliberately traditional, with lap siding, trim details and a cottage profile that sits comfortably next to Craftsman and older Seattle-area homes. The bathroom includes a tub and shower, which matters to families with young children and to tenants who expect one.
The Country Cottage’s Ideal Household
Shared households where privacy between bedrooms is a priority, owners whose main house has a traditional style, and rental owners targeting tenants who need two rooms.
Cedar Groove: Two Bedrooms with More Everyday Function
Cedar Groove is only slightly larger than the Country Cottage, but it uses the space differently. The kitchen has an island for prep and casual meals, the dining area is defined within the great room, and laundry gets its own room instead of sharing a closet. A separate mechanical space keeps the water heater and equipment out of living areas, and the front porch and rear patio extend the home outdoors.
When Cedar Groove Is the Right Call
Small families, long-term tenants who cook at home, and anyone who plans to live in the unit full time rather than use it occasionally. The extra function makes Cedar Groove feel closer to a small house than to a guest suite.
The Garage Version
Cedar Groove is also offered in a version with a garage. On lots where you are losing an existing garage to make room for the ADU, or where covered parking and storage matter, this variant solves two needs in one structure. It needs a wider footprint, so check it against your lot early.
Â
Comparing What Matters Day to Day
Bedrooms and Privacy
Main St has one bedroom. The Country Cottage separates its two bedrooms across the house for privacy. Cedar Groove offers two bedrooms in a layout that favors a central, family-style living area.
Kitchen and Dining
Main St and the Country Cottage combine the kitchen with the living room. Cedar Groove adds an island and a defined dining zone, which makes a real difference if the occupant cooks every day.
Laundry and Storage
Main St tucks stacked laundry into its pantry. Cedar Groove gives laundry a separate room. In every plan, built-in storage is part of the design, because small homes become cluttered quickly without it.
Outdoor Living
Cedar Groove’s porch and patio are designed into the plan. For the other two, outdoor space is shaped by how the unit sits on your lot, and a small patio or deck can be added during site design.
How Lot and Code Shape the Choice
On most residential lots in the Seattle area, the current rules allow ADUs of up to 1,000 square feet, so all three plans fit within typical size limits. What usually decides the choice is the lot itself: rear yard depth, setbacks, lot coverage, existing trees, and how much of the yard you want to keep. A 550-square-foot plan leaves noticeably more garden than an 800-square-foot one. In Seattle, our guide to Seattle ADU and DADU rules explains which limits apply, and HB 1337 by city covers the rest of the region.
Single-story plans also avoid many of the privacy and shading questions that come with taller backyard buildings, which can make conversations with neighbors easier.
Choosing Between Them
Choose Main St if one bedroom is enough and keeping yard space or fitting a tight lot matters most.
Choose the Country Cottage if two adults will share the home and each needs a private bedroom, or if a traditional exterior matters.
Choose Cedar Groove if the unit will be a full-time home where cooking, laundry and outdoor space get daily use, or if you need the garage version.
From Plan to Your Backyard
Every plan is a starting point. Finishes, window placement, exterior colors and some layout details can be adjusted to your lot and goals during design. The three plans also belong to different size categories in our packages, so browsing the compact ADU category and the full set of ADU and DADU packages is a quick way to see what is included with each. When you are ready to check your own lot, request a free lot feasibility report.
FAQ
Can a 550-square-foot ADU feel comfortable for two people?
Yes, if storage is planned carefully. The Main St layout uses a walk-in closet, pantry and built-ins so the open living space stays usable for two.
Is a two-bedroom ADU worth the extra square footage?
It depends on use. For rentals aimed at roommates or families, and for households that need a home office or caregiver room, a second bedroom adds flexibility and appeal.
Can I change the layout of a pre-designed ADU plan?
Many details can be adjusted, such as finishes, windows and some interior arrangements. Larger structural changes may require additional design and engineering time.
Do these plans come with a garage?
Cedar Groove is available in a version with a garage. Main St and the Country Cottage are designed as standalone homes.
Where can I see current pricing for each plan?
Each plan has its own page in the ADU plan collection with current pricing details. Pricing depends on the lot, finishes and site work, so a site visit and design are needed for a final number.