This detached backyard ADU fits 310 square feet of living space on one level, within a footprint of 21'-8" × 15'-9". There is no separate bedroom. The studio living and sleeping room, at 10'-2" × 13'-9", is the main space, and it is entered from the porch, so you step directly into the room where you sleep, sit and eat.
The kitchenette (8'-4" × 6'-0") and the bath (8'-4" × 4'-1") both open off the studio. The bath includes a stacked washer and dryer, which keeps laundry out of the living area. Every room is reached directly from the studio, so the plan has no hallways and little wasted floor. The plan has no garage.
Layout highlights
- Studio living and sleeping room measures 10'-2" × 13'-9" and serves as the main space.
- Kitchenette of 8'-4" × 6'-0" opens directly off the studio room.
- Bath with stacked laundry fits in 8'-4" × 4'-1" without a separate laundry closet.
- Overall footprint is 21'-8" × 15'-9" on a single level, with 310 sq ft of living space.
- Entry porch leads straight into the studio, with no hallways between rooms.
Room sizes
| Room | Size | Area |
|---|---|---|
| Studio Living/Sleeping | 10'-2" × 13'-9" | 140 sq ft |
| Kitchenette | 8'-4" × 6'-0" | 50 sq ft |
| Bath with Stacked Laundry | 8'-4" × 4'-1" | 34 sq ft |
Who this plan suits
This plan suits homeowners adding a rental, guest unit or home office in the backyard, or housing for a family member. It needs a lot with room for a 21'-8" × 15'-9" footprint plus the setbacks your local code requires.
How this plan was made
It was generated in AI Architectures Plan Studio from this one-line brief: “Detached backyard ADU (accessory dwelling unit) with about 300 sq ft of living space: studio (no separate bedroom), 1 bath, studio: one room for sleeping and living, kitchenette, bath, stacked laundry.” An AI architect drafted the room program, a layout solver placed every wall and door, and the plan was checked automatically for room sizes, circulation and daylight. The same project produced the PDF sheets, layered DXF, IFC model and 3D model you can download above.
Frequently asked questions
What are 300 sq ft ADU plans?
They describe a small accessory dwelling unit of about 300 square feet, built on the same lot as a main house. This version has 310 sq ft of living space as a studio with a kitchenette, one bath and stacked laundry.
What affects the lot and cost of building this ADU?
The 21'-8" × 15'-9" footprint must fit within your setbacks and any rules on separation from the main house. Cost depends mainly on your local permit requirements, utility connections to the main house, foundation type and finish choices.
Can I change this plan by chat?
Yes. You can describe changes in chat, such as moving rooms, changing the porch, or adjusting the layout for a narrower or wider lot. This plan has no garage, so garage side does not apply. The plan is updated to match your request.
How do I use the PDF, DXF and IFC files?
The PDF is for reviewing the layout and sharing it with a builder or permit office. The DXF opens in CAD software for drafting and editing, and the IFC imports into BIM tools for coordination. Have a local professional check the plans against your local code before you build.