M-400: 1 Bedroom 400 SF ADU

Area 400 SF
25' x 16'
1 Bedroom
1 Full Kitchen
1 Full Bathroom
1 Laundry
1 Closet
can be 100% customizable to your needs

All Features and Highlights Included

model overview
Area 400 SF
25' x 16'
1 Bedroom
1 Full Kitchen
1 Full Bathroom
1 Laundry
1 Closet
FLOOR plan M-400 / 25' x 16'
M-400: 1 Bedroom 400 SF ADUFloor Plan
100% Customizable
  • Adjust ADU size & shape
  • Choose any exterior & interior finishes
  • Set room configurations
  • Customize kitchen & bathroom
  • Include accessibility features / ADA compliance
  • Add, remove & move windows & doors
  • Incorporate any storage solutions
  • Integrate patio, deck, garage or loft
  • Choose your own customization
  • And more customization options to fit your unique needs!
Best Suited For
  • Family Comfort
  • Senior Living
  • Prime Rental
  • Solo Rental
  • Short-Term Rental
  • Game Space
  • Craft or Hobby Room
  • Space for Kids
FLOOR plan M-400 / 25' x 16'
M-400: 1 Bedroom 400 SF ADUFloor Plan
Full Kitchen
  • Functional solid wood cabinetry
  • Premium materials throughout
  • Soft-closing cabinets and drawers
  • Durable stone countertops
  • Optimized kitchen triangle for efficiency
Complete Bathroom
  • Full-size shower/tub combination
  • Waterproof, easy-to-clean materials
  • Low water consumption fixtures
  • Effective moisture control
  • Functional vanity with storage
Efficient Appliances
  • Energy-efficient heat pump
  • Dishwasher, 24"
  • Slide-in range, 30"
  • Refrigerator, 30"
  • Microwave hood, 30"
Functional Amenities
  • Spacious storage solutions
  • Energy-saving LED lighting
  • Dedicated laundry area
  • Adjustable climate control
  • Zero-threshold interior for accessibility

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ADU Models and Designs

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S-250
S-250
Area 259 SF
18'6" x 14'
1 Cozy Studio Space
Full Kitchen
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S-300
S-300
Area 301 SF
21'6 x 14'
1 Cozy Studio Space
Full Kitchen
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S-380
S-380
Area 380 SF
20' x 20'
1 Cozy Studio Space
Full Kitchen
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S-400
S-400
Area 400 SF
20' x 20'
1 Cozy Studio Space
Full Kitchen
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S-470
S-470
Area 473 SF
21' x 22'6''
1 Cozy Studio Space
Full Kitchen
More
M-300
M-300
Area 298 SF
13'6 x 27'6
1 bedroom
Full Kitchen
More
M-330
M-330
Area 330 SF
20'x 16'6
1 Bedroom
Full Kitchen
More
M-370
M-370
Area 370 SF
19' x 19'6
1 bedroom
Full Kitchen
More
M-400
M-400
Area 400 SF
25' x 16'
1 Bedroom
Full Kitchen
More
M-500
M-500
Area 500 SF
25' x 20'
1 Bedroom
Full Kitchen
More
M-520
M-520
Area 520 SF
20' x 26'
1 Bedroom
Full Kitchen
More
M-550
M-550
Area 550 SF
26'x 23'6''
1 Bedroom
Full Kitchen
More
M-600
M-600
Area 600 SF
25'x24'
1 bedroom
Full Kitchen
More
M-800
M-800
Area 799 SF
42' x 25'
1 Bedroom
Full Kitchen
More
L-465
L-465
Area 459 SF
25'6'' x 18'
2 Bedrooms
Full Kitchen
More
L-545
L-545
Area 543 SF
26' x 23'
2 Bedrooms
Full Kitchen
More
L-580-2
L-580-2
Area 580 SF
11'6x25'
2 bedroom
More
L-650B
L-650B
Area 646 SF
27'6" x 27'
2 bedroom
Full Kitchen
More
L-650A
L-650A
Area 650SF
24'6 x 26'6
2 bedroom
Full Kitchen
More
L-690
L-690
Area 690 SF
20' x 34'6
2 Bedrooms
Full Kitchen
More
L-749B
L-749B
Area 749 SF
21'6'' x 36'6''
2 bedroom
Full Kitchen
More
L-749A
L-749A
Area 753 SF
25' x 35'
2 Bedrooms
Full Kitchen
More
L-760
L-760
Area 757 SF
28' x 27'
2 Bedrooms
Full Kitchen
More
L-800-2
L-800-2
Area 800 SF
22' x 18'6
2 bedroom
More
L-900
L-900
Area 896 SF
32' x 28'
2 Bedrooms
Full Kitchen
More
L-920
L-920
Area 913 SF
41'6 x 22'
2 Bedrooms
Full Kitchen
More
L-1080
L-1080
Area 1080 SF
45'x24'
2 bedroom
Full Kitchen
More
XL-749
XL-749
Area 743 SF
31' x 28'6
3 Bedrooms
Full Kitchen
More
XL-1100
XL-1100
Area 1000 SF
40' X 25'
3 Bedrooms
Full Kitchen
More
XL-1200
XL-1200
Area 1200 SF
40' x 30'
3 Bedrooms
Full Kitchen
More

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    Energy Efficiency and Sustainability
    Mold-Free Interior
    Waterproof
    Interior Surfaces
    33%
    Water Consumption Cut
    40%
    More Effective Insulation
    100%
    Resistant to Pests, Mold & Rot
    20%
    Lower Bills More Efficient HVAC
    60%
    Greater Energy Efficiency
    80%
    More Cost-Effective Lighting
    Toxic-Free Materials
    50%
    Less Noise With Solid Materials
    4xFaster
    Preparation Process
    0
    Supply Chain Disruptions
    Lifetime Warranty
    on Select Materials

    400 SQ. FT. ADU

    Small but totally independent second houses are a trend nowadays. Lots of modern homeowners construct them because of their versatility, convenience, and ability to increase property value. For such a house, even 400 sq. ft. with one bedroom can be enough. It may fulfill different practical purposes — a granny flat, a guest house, a home office, a personal mini-cinema, or an art studio. You can also use it to generate rental income. With efficient design, the right ADU floor plans, and some optional add-ons, you may give it a rather spacious feel and even turn it into a combined living area.

    In our article, we’ll talk in detail about the main characteristics, types, and advantages of 400-square-foot ADUs.

    Types of 400 Square-Foot ADUs

    Firstly, let’s give a definition of an ADU (accessory dwelling unit). It’s a secondary home that shares the property with the main one.

    There are many ADU design types and variants. Usually, specialists divide them into several large categories:

    1. Attached. These accessory dwelling units have a connection with the main home — typically a wall or even a roof. Such an ADU floor plan is perfect for aging family members with specific needs;
    2. Detached. It’s a completely separate living area. A detached ADU can be a great living space for guests;
    3. Converted. This is an already-existing building (for example, a garage) turned into an accessory dwelling unit. It’s the cheapest and easiest ADU to create because its outer walls are already here. You’ll just need to make some modifications — change its space layout, install windows, inner walls, and the main entrance. However, getting a permit is necessary for it too;
    4. Junior. It’s a small dwelling unit whose size mustn’t exceed 500 sq. ft. In California, you can create it on your property, even if you already have an ADU of any other type.

    Also, ADUs can be prefab or stick-built. The first type is a living space constructed in a factory. It requires a minimal building process (or none at all). It’s faster, more convenient to make, and sometimes cheaper, but its floor plans are not customizable. The second type is a traditionally-constructed ADU. You can customize its drawings as you wish, change its bedroom type roof size, add some extra storage space, and so on.

    All those ADU types are completely habitable. Their floor plans can include a bedroom, a bathroom, a kitchen, and a living room.

    400 Square-Foot ADUs: the Biggest Advantages

    Tiny houses have multiple benefits in comparison to larger ones.

    The main ones are the following:

    • Faster completion and lower maintenance. The smaller a home is, the easier it is to create and maintain afterward;
    • Availability. Not only does the building itself have lower pricing, but all the payments connected to it are also significantly smaller — mortgage, temperature regulation, electricity, and so on. Moreover, in California, ADUs are smaller than 750 sq. ft. Aren’t subject to impact fees;
    • Fewer materials, decorations, and furniture, which is also can help you save lots of money;
    • The necessity to live a more active life. A tiny home may be comfortable and have a cozy interior, but its square footage is not large enough to spend the whole day inside it. So, you’ll need to go outdoors more often, which is a far healthier lifestyle.

    So, a 400-square-foot ADU floor plan can be an ideal option for you. It has plenty of advantages in comparison to larger houses. Also, despite its small size, it can have features such as a storage loft, clerestory windows, and many others.

    If you want to get this tiny home in your own backyard, contact us and order our services. A+ is a general contractor company that has all kinds of professionals, including designers, builders, and structural engineers. We can do every part of the construction process, from estimating the costs and making the ADU floor plan drawings to doing site work and interior design. By the way, we offer cost estimation completely for free in a very convenient file format!

    Frequently Asked Questions — FAQ

    What does a 400-square-foot space look like?

    If you’re unsure what this size resembles, you can imagine a large bedroom or a big garage. Such an ADU is comfortable, functional, and suitable for living. It can be a full-fledged housing unit whose floor plan includes a bathroom, a toilet, one bedroom, and a kitchen with a table and a seating area. But, of course, it isn’t very large.

    How much does it cost to build a 500-square-foot ADU in California?

    Typically, a modern 500-square-foot ADU costs around $150,000. Its price depends on the ADU floor plan, its type, location, additional features, and other details.

    What is the cheapest option for an ADU?

    The cheapest ADU design variant is a garage or room conversion. Its cost usually around $110,000. To convert a garage, attic, or basement into a living space, you won’t need to construct walls — you’ll only have to change its layout (make a bedroom, a kitchen, a bathroom, etc), add interior design, furniture, utilities, and decorative features.

    Is it worth it to build an ADU in California?

    Of course, it is! In addition to multiple functions that an ADU can fulfill (a granny flat, a home office, a guest house, etc.), it can significantly increase your property value. In most cases, property parcels with ADUs cost 20-30% more than without them.

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