Accessory Dwelling Unit

An accessory dwelling unit is a small home built on the same property as your primary residence. The ADUs contain one or two bedrooms with a separate kitchen and bathroom. You can use existing space in your home, like the basement, or build an entirely different structure in the backyard of your property.

ADUs have multiple purposes, including extra space for family, office space, or a rental unit to generate more income. Regardless of the type of ADU you choose, the decision creates affordable housing options for families and outside renters.

When constructing an ADU on your property, you must consider several factors, including the design, your budget, and the purpose of the unit. Before you begin your project, it is important that you look into the state and local zone regulations for this type of project. This helps ensure you receive the necessary permits to proceed with your project.

For a successful project, you will need our expert guidance at Orange County Home Remodeling. We have the knowledge and expertise you need to design and install an ADU in your Orange County, CA, home.

What is an Accessory Dwelling Unit?

An ADU is an additional living space to rent or host a family in your home. You can construct an ADU using the already available space in the home or a separate building within the home. The exterior of an ADU looks like a tiny version of the main house. This is because most homeowners want to match the outlook of their main house with the ADU.

Remodeling a space in your home, like a garage or basement, is the easiest way to construct an ADU. However, for maximum privacy and more living space, you may need to build another structure in the backyard.

California has enacted several laws to support the development of ADUs. With the help of the state's ADU program, many homeowners can convert their backyards and garages into living spaces for family members or tenants. Another objective of the ADU program is to ensure the proper use of urban spaces.

Types of Accessory Dwelling Units

ADUs come in different shapes and sizes. Often, these structures are classified into three different categories:

  • Detached ADU. This type of ADU could transform your backyard into a different unit.
  • Attached ADU. With an attached ADU, you just create an attachment to the primary home.
  • Conversion. A conversion ADU, or junior accessory dwelling unit, is made by converting your garage, basement, or bedroom into a separate dwelling unit.

Some of the common types of ADUs you can build in your Orange County home include:

Basement ADU

A basement ADU and a refinished basement are different things. Your basement will be classified as an ADU if it has separate plumbing and ventilation for a kitchen and bath. If you already have a basement in your home, converting it into an ADU would be sensible. Basements often have the correct dimensions for an additional housing unit but are not always utilized to their full potential.

If you want to build an ADU in your basement, ensure a separate entrance that does not go through your main living room. Additionally, you may need to install new walls, floors, and ceilings to ensure the place is livable.

Another consideration you must make when converting your basement into a rental-space ADU is the height requirements. If your unfinished basement has a low head height, you can dig down into the floor to meet your needs. With a basement ADFU, you must consider proper lighting and the utilization of natural light. You can do this by installing large windows.

Basement ADUs make suitable rental spaces with more privacy than street-level apartments. Since the basement is a pre-existing structure, you can profit significantly from renting the space.

Backyard Cottage ADU

A backyard cottage is a detached living space with the appearance and feel of a house. This type of ADU may be suitable for you if you have a large backyard. With a cottage ADU, you must have separate water, electricity, and sewage for the additional unit. Cottage ADUs are an excellent option for independent living spaces.

Some considerations you should make when building a backyard cottage on your property include the appearance and location. You want to maintain the aesthetics of your home with a well-designed ADFU unit. Therefore, you will require a professional remodeling expert to help you match the appearance of the cottage to your primary residence. Another consideration for a cottage ADU is its location. Placing the unit against the lot line is a wise idea. However, you must be mindful of the height restrictions.

The main benefit of a cottage ADU is increased privacy. Since the cottage is a separate unit, you can install additional privacy features like a small fence. Due to the increased space and privacy, a cottage ADU will fetch you more rental income.

Garage Apartment

Most apartments in California have a detached garage with living space on top. You can convert the garage space into a rental or office ADU. If you have a two-vehicle garage, adding living space on top of it can be a good investment.

The garage layout makes converting it into an ample living space easy. You can separate the ADU from your main living area by creating a separate entrance on either side of the garage.

Other Spaces

You can use any home space when creating an accessory dwelling unit. If you have an extra room or space, you can convert it into a rental area. The most important consideration with the attached ADU is access. You will need to have a different entryway for the tenants. When you convert a space in your house to an ADU, you must create fire- and sound-proof separations. The attached ADU is a good option for compact spaces, and there is less need for separation.

Benefits of Accessory Dwelling Units

The following are some benefits you will accrue from adding an ADU to your property:

Extra Income

Adding an accessory dwelling unit is a great investment if you are a homeowner looking for extra income. Renting the unit to a family or other renters will give you the extra income you need. If you want to rent out your ADU, you must ensure it has a separate entrance, kitchen, and washroom.

This ensures the unit is a separate living area from your main house. The amount you receive from renting an ADU is more than you would earn from investing in a new property. With a new property, you must pay high land rates and increased water and electricity connectivity costs.

You can easily tap electricity and water from your main system for accessory dwelling units.

Increase in Property Value

In addition to receiving passive income from your accessory dwelling unit, building the ADU increases your property value. By converting your basement or garage into a separate living space, your home could be highly valued. You can use this investment as a selling point.

Most buyers are willing to pay more for a property with an ADU. This is because of the convenience and additional income that come with it.

Additional Space for Family and Guests

An ADU makes a lot of sense when you host family or friends for a prolonged period. The accessory dwelling unit is a convenient option to ensure comfort and privacy for you and your guests.

Low-Cost for Caretakers and Senior Family Members

Building an ADU is a great way to keep elderly parents and grandparents close to you and in a comfortable space. Assisted living can be costly. Therefore, if you do some remodeling to your home and add a separate entrance for these individuals, you can take care of them while saving on the cost of care.

Workout or Home Office Space

Building an ADU can be a perfect way to create ample office space if you live in an urban area or work from home. Separating from your primary home will make the ADU feel like a faraway and peaceful place to do your work. Additionally, you can save on renting office space in a busy and noisy city.

Permits Needed when Building an ADU in Orange County

Building an ADU in California has been a highly complex process in the past few years. However, the less strict zone controls and the reduced permitting process have streamlined the process and made it easier for many homeowners. However, you cannot wake up one day and decide to build an ADU. There are still some rules that you must follow. Some of the permits you will need to build an ADU include the following:

Building Permit

You will need a building permit before adding a habitable space to your property. However, the permit is only issued when you comply with your city's height and space restrictions. Applying for a building permit requires submitting a detailed plan of your project drawn to scale.

If you work with a remodeling company for your ADU, they will help you prepare the application materials necessary for your building plan. Additionally, you may need plumbing, electrical, and mechanical permits. Before applying for a building permit, familiarize yourself with the local ADU building requirements.

In addition to securing a building permit, you may also require permits for the following:

  • ADU location. If residential uses are allowed, you can have an accessory dwelling unit on your property. This means that you must have an existing single-family or multi-family home.
  • Minimum lot size. There is no minimum home size restriction for individuals who want to build an ADU.
  • Site-specific conditions. If building your accessory dwelling unit will affect your neighbors, you will require an easement permit. This will be a requirement for individuals who build their ADUs near utility easements.
  • Address assignment requests. You must submit an address assignment request to ensure that your ADU has a separate address from the accessory dwelling unit on the lot.

Factors to Consider When Building an ADU on Your Property

Building an accessory dwelling unit may be the right option if you are looking to create a separate space for a family, a workspace, or a rental opportunity. Although ADUs have endless benefits, building one could be complicated, given the different zoning restrictions. The following tips will guide you in building your unit:

  • Ensure that your Property is Suitable for an Accessory Dwelling Unit

Before you start building an ADU, you must ensure that the specific plan can be successfully built on your property. Additionally, you must ensure that your property meets the zoning regulations. This helps ensure you quickly receive the required permits to continue your project.

  • Build the ADU on your Property

When you are searching for investment properties, you must pay a premium for the land. However, the land premium is priced into the existing land for an ADU. With the high land costs in Orange County, building a rental unit on your property will be more profitable.

  • Utilize a Standardized Plan

Utilizing a standardized plan when building your ADU offers selection, cost savings, and planning benefits. Additionally, these plans can be customized to meet your city's requirements.

  • Consider an Attached ADU

Most homeowners think of ADUs as detached units or garage conversions. However, an ADU can be a unit attached to your primary home. Building an attached ADU helps save on yard space and increases the unit's square footage. Additionally, you can save on solar costs associated with detached units in California.

  • Evaluate the Benefits of Building an ADU

Building an ADU is an intelligent decision. With the additional income you receive from renting the unit, you will be able to pay for your mortgage.

  • Research Before Starting the Project

While building an ADU may seem easy, you must ensure you are well-versed in different regulations. Before you start your projects, you should not have pending liens or pre-sale inspection steps. When you want to convert an existing space, like a garage or bedroom, into an ADU, you should look into the permits you need to move forward.

  • Consider your Budget

For any home remodeling project, the budget is a critical aspect. When making a plan, you must ensure that the money allocated for the project is enough to make the specific design.

  • The desired Privacy Level

An ADU can have different functions, including office space and a rental unit. Most ADUs are permanent structures with a real foundation and utility connections. If your main aim for building the ADU is for rental purposes, you must consider the level of privacy you need for yourself and your family.

The privacy issues may be manageable if you rent the ADU to a family member. However, if your unit is open to rental by outsiders, you must consider additional features like landscaping and fencing to maintain your privacy.

  • Utility Connections

Like your primary residence, an ADU will require water and electricity. You can save on installing new systems by finding a contractor to tap the electricity and moisture from your primary residence. The only exception will be the septic tank. Sometimes, your existing septic tank may be unable to hold another waste source. Therefore, you may need to upgrade the septic system or build a small one for the ADU unit.

  • Cost of Building an Accessory Dwelling Unit in California

The cost to build an ADU in your home varies depending on the type of ADU you want. Detached ADUs, like a cottage apartment, may cost more than a basement apartment. This is because you begin construction on the unit at the foundation. Your construction cost for an ADU will cover the materials and labor needed to build the unit. These items include:

  • Flatwork and foundation.
  • Excavation.
  • Roofing.
  • Flashing and gutters.
  • Plumbing.
  • Electrical connections.
  • Flooring.
  • Fireplace.
  • Septic.

How many Accessory Dwelling Units Can I Have?

The number of ADUs you can have in your home varies depending on the existing structures. If your family is constructed for a single family, you can build:

  • One detached ADU.
  • One attached ADU.
  • One junior accessory dwelling unit.

However, before you construct the junior accessory dwelling unit or a detached ADU, the unit must meet the size requirements for single-family living.

Find an Expert Home Remodeling Service Near Me

Adding an extra living space like a detached cottage or a small home is a popular home renovation project among property owners in California. An ADU creates a separate living space with the same utilities as a family home. These units can either be made from an existing space in the home or by creating different structures within the compound.

Due to the red-hot housing market and the increase in the price of land, ADUs have risen significantly. Building an ADU involves making a detailed plan and obtaining the necessary permits to begin the project.

ADUs provide numerous benefits for homeowners, including an additional income to help cover your mortgage. However, before deciding to make this home renovation, you must make several considerations, including the project's cost and privacy in your home.

At Orange County Home Remodeling, we offer a solution for all your home remodeling needs in Orange County, CA. Contact us at 657-660-3481 today to discuss your project.


Orange County Home Remodeling has a team of skilled contractors focused on one goal: providing superior designs, outstanding workmanship, and individualized customer service for the most outstanding home remodeling and renovation projects in the Orange County region. We are insured, licensed, and bonded, and with combined years of experience, you can trust us to do the job right the first time. Call us today at 657-660-3481 to get started on your home remodel project.

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