1 Bedroom ADU Floor plans

1 Bedroom ADU Floor Plans

50+ One Bedroom Floor Plans From 500 to 900 Sq Ft.

Pick a plan that fits your family needs and property.

One bedroom ADU floor plans come in many layouts. Most prefabs will be I shaped or L shaped. But you can maximize your backyard potential with a custom shape.

The best ADU Floor Plan meets all family needs and reflects the shape of your main house and property line. Your new ADU should look like it has always been there. It should also maximize the space – take as much of your backyard as you are willing to dedicate to the new living area.

What are the benefits of 1 bedroom ADU floor plans?

Technically, the house this size may even be considered a tiny home. It may be a good fit for either a young family or a retiree who wants to be close to her grandkids. No compromises on bathroom, kitchen or living room space expected.

What ADU floor plan will make the most of your backyard?

Hint: the ones that fit your backyard like a lost piece of a puzzle.

Case study: One bedroom ADU Floor Plan

One of our 1 bedroom ADU plans: 600 sq ft with one bathroom


The homeowners were looking to maximize the size of the ADU. Even though it would have been possible to crane in a modular unit, the size of it would have been ~400 sq ft. While with a custom design, we were able to fit 600 sq ft one bedroom ADU.

  • Designed for grandma
  • With space for favorite furniture
  • Easy in cleaning and maintenance
  • Matching the look and style of main house


The size of this ADU was determined by the distance to the property line, distance to the walls of the main house, property lines and public utility easement.

The shape was driven by the pie shape of the lot.

1 bedroom 1 bathroom floor plans
Currently in construction


A bigger bathroom accommodates the necessary area for a wheelchair turnaround if it is ever needed, has a spacious “walk-in” shower. 

The living room has vaulted ceilings  with a bay window looking into the backyard. 


From 300 Sq Ft to 600 Sq Ft - see what fits in each floor plan size

Popular 1 Bedroom ADU Floor Plans

400 sq ft ADU Floor Plan

Reasonable size for a small I shape one bedroom dwelling unit. The bathroom has enough space for a tub. The size of the kitchen can be adjusted according to your needs.

ADU Floor Plans 500 sq ft

This L shape one bedroom one bathroom house can be cosily tucked into the corner of the backyard – leaving privacy for the residents of both – main house and ADU.

600 sq ft ADU Floor Plan

This one bedroom one bathroom can be executed in an T shaped or L shape layout depending on the space in your backyard. The layout is usually governed by access and privacy considerations.

Whichever ADU floor plan you select, you will not pass a final inspection without these features

Essentials for any of our 1 bedroom ADU floor plans


Type of insulation is called out in your Title 24 report provided by your energy consultant or HERS rater.

Kitchen Appliances

All ADU floor plans should show sink, cooktop, hood and fridge. These items are essential for anyone living permanently in the ADU.

Fire and CO2 Alarm

Smoke and carbon monoxide alarms are required on the wall or ceiling outside of each sleeping area. 

HVAC and Ventilation

Ductless mini splits are an accepted way to heat and cool your ADU. Energy Recovery Ventilators are an energy-efficient way to maintain indoor air quality.

Water Heater (Heat Pump)

As California goes all electric, think about the sizing of your pump – it depends on the number of people living in the ADU.

Address Numbers

ADUs are often required to have two sets of a minimum of 4 inch high house numbers – with one on ADU and an extra that is seen from the public road.

1 bedroom ADU sounds overwhelming?

We make it easy to get started


Create property site plan

Let us answer three questions together: 1. How big can you build? 2. How much of a backyard can you dedicate to new living space? 3. How much can you afford to spend on construction.


Select the best 1 bedroom ADU floor plan

We do not like to invent wheels or bicycles. Let us get started with the plan that fits most of your requirements and then tweak it to make it shine in your backyard.


Assign the team

The success of a construction project hinges on how well the team communicates. You have a contractor you like? Bring her on board. We are happy to support you with the design, engineering and construction – when needed.


Gather Necessary Documents

Let us start with the best information available. What do you already have? Title report. Floor plan or site plan of your main house. Survey. Soil report. All these documents are a great foundation for your future successful construction project. Pun intended.


Compile the permit plan set

The number of pages in your plan set can differ from 8 to 140 (no kidding). It all depends on property specifics and city (or county) requirements. The better prepared your first submission is, the faster you get your permits. 


Respond to Plan Checker comments

Do you know that the most frequent reason it takes such a long time to pull permits is the number of weeks that passed between the day the city had given plan check comments and the day your team responded to them?

Three pillars of a well designed home

What you need to consider for your 1 bedroom ADU?


From traditional slab and pier options to hybrid foundations that use helical screw piles – the final choice needs to be evaluated on the basis of backyard access, feasibility, budget and house designs.


California is going all electric. This means your water heater will be electric. So will your HVAC heat pump and cooktop. You will be required to put some solar panels on the roof as well. All this needs a 200A + electric panel. 

Natural Light

We love indoor-outdoor seamless flow and having lots of natural light. It often comes at the expense of energy efficiency. You can compensate for it with better quality windows with a lower U factor.