Today, ADU or Accessory Dwelling Unit is considered as one of the most sustainable and versatile housing solutions. Otherwise known as backyard cottages, in-law suites, or granny flats, ADUs provide you the chance to optimize your property’s potential, obtain additional income streams, and respond to housing shortages.

Here, we are going to learn more about ADU construction, its benefits, design restrictions, and the steps required in constructing your own ADU.

What are ADUs?

ADUs are considered secondary residential units that can be constructed on the same property as the existing residence. ADUs can either be standalone (built as a separate structure in the yard) or attached to a house, such as a garage or a basement. ADUs can vary based on their purpose, style, and size, making them a versatile solution for your various needs.

What are the Advantages of ADU construction?

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Choosing to build your own ADU, whether as a separate structure or as a stand-alone, can provide you with several benefits, the following are just some of them:

Your ADU can be rented out to provide you with an additional source of income. This extra income can be contributed to your investments or savings and can even be used for your mortgage payments.

Constructing an ADU can greatly help in boosting the market value of your property. This added value on your property can be an enticing selling point if you have plans of selling your property in the future.

Most often, ADUs do not require a lot of resources, at the same time, they only have a smaller carbon footprint than typical houses, making them eco-friendly and sustainable.

ADUs can also be used for accommodating adult children, aging parents, or even extended family members while enjoying independence and privacy.

In specific areas where there is a high population, ADUs can be the best solution for housing shortages. It can be a great housing option without requiring large-scale development.

Important Design Considerations for Your ADU

Before you start your journey on ADU construction, there are important factors to consider:

  • First, you need to figure out the main purpose of your ADU. Is it for your guests, relatives, or for your additional income? This can greatly influence the layout and design of your ADU.
  • You need to create a budget that incorporates the materials, labor, design fees, permits, and any other unexpected expenses.
  • Learn more about the building codes, local zoning laws, and permit requirements. Keep in mind that these regulations can likely differ depending on your location, so it is significant that compliance should be assured.
  • Be sure to select the appropriate style and size that fits your needs and property.
  • ADUs can either have a traditional, contemporary, or modern design. Its size can range from two-bedroom units to small studio rooms.
  • In addition, it is important to consider how you are going to connect your utilities, including sewage, electricity, and water, to your ADU. Is it going to be a shared or a separate connection? Keep in mind that this can affect the plans and the costs.

How to Start Your ADU Construction

The following steps can guide you in building your own ADU:

  • First, you should have a well-thought-out plan and be sure to secure approvals and essential permits from your local government.
  • You can either choose to do it yourself or hire a reliable contractor to do it on your behalf. Unless you have the expertise and experience, it is recommended that you should hire a contractor to do it for you. Prepare yourself for the construction process which could take a while.
  • Figure out where you will obtain funding for your project. Is it going to be from your loan, personal savings, partnership, or grants?
  • You can have the option to customize the interior design of your ADU to fit your intended purpose. This includes the furnishings, fixtures, appliances, flooring, etc.
  • Make sure that the sewage, electricity, and water connections are properly installed to satisfy the needs of your ADU.
  • Lastly, you should also consider if the ADU complements the landscape design and the entire property. This includes the outdoor living areas, walkways, parking, etc.

How Do You Choose the Best Contractor for Your ADU Construction?

Building an ADU or Accessory Dwelling Unit can be one of the most dramatic changes to your property. Nevertheless, your ADU project can only be successful if you know how to choose the best contractor.

With a myriad of options available, selecting the best contractor can be a challenging task. Fortunately, the following guidelines can help you choose the ideal contractor to ensure that your ADU project is a success.

Determine Your Project Needs

Before you start searching for a contractor, you need to clearly define the timeline, budget, and scope of your ADU project. Try to figure out whether you require a stand-alone ADU, a conversion, or a customized ADU. Having a well-thought-out plan can help you effectively communicate your requirements to your contractor.

Find Local Contractors

You can start by searching for local contractors who are experts in ADU construction. To do this, there are various resources that you can use, including local directories, online platforms, or recommendations from your neighbors, friends, co-workers, relatives, or real estate professionals. Try to choose contractors who have years of experience, a remarkable reputation, and a portfolio that matches your requirements.

Verify Licensing and Credentials

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Be sure that your potential contractor is bonded, insured, and licensed. It is also important to note that licensing requirements can vary depending on the location, so ensure that the contractor adheres to your local regulations.

Insurance is vital since it can provide protection for you and your contractor in the event of accidents or unexpected issues that could occur during construction.

Check References and Portfolios

It is crucial that you ask your contractor for portfolios of their prior ADU projects. This can help you review their work, including their style and craftsmanship.

In addition, you could also ask for references from their previous clients so that you can contact them and learn about their experiences with the contractor. This can give you some insights into the contractor’s budget and meeting deadlines, as well as determining customer satisfaction.

Conduct Interviews

After having a shortlist of prospective contractors, interview them one by one. During these meetings, you can talk about the details of your project, such as your preferred timeline, budget limitations, and most of all your vision. Observe if the contractor will listen attentively to your needs and discuss his approach to the project.

Ask for Detailed Quotes

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For each potential contractor, request a detailed quote for your ADU construction. This quote should consist of labor, materials, a breakdown of costs, and the expected timeline. Be cautious of contractors who refuse to give you a detailed estimate, since this could result in unforeseen costs down the road.


ADUs can provide you with sustainable and flexible solutions to your various housing requirements. Whether you want to accommodate your growing family, generate extra income, or simply add value to your property, ADU construction is the ideal investment. With a carefully thought-out plan, obliging local regulations, and implementing a unique design, you can improve the value and functionality of your property while making a great contribution to the community.

Cardinal Custom Construction can help you with your ADU construction. For more information, you can call us at 650-714-5103 or write to us at