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Shell ADU

Your ADU journey starts here with our

innovative design,
prompt construction,

and value-driven solutions

Garage Conversion ADU Design & Build

Transform an unused garage into a vibrant living area, morphing this space to suit your unique needs, whether a studio, home office, or extra bedroom.

Custom ADU Cost Calculator

These calculations are derived from the 2023 Big Data Research, and provide a general approximation.
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The Path to Your ADU

Choose between in-house or online free meeting with our ADU Consultants to discuss your project
Our experienced team drafts a detailed estimate, which we then finalize together to align with your vision and budget
We sign a contract, finalize the designs, and our team kicks off the plans and permit process
Relax as our efficient construction process unfolds, ensuring a stress-free experience

Our Recent Projects

Looking for ways to expand your living space without buying an additional property? An accessory dwelling unit is a great option for those who want to increase their housing and add more functionality to unused parts of the lot. With the right contractor, you will be able to create an affordable living space that can be utilized for a variety of purposes. Moreover, having their own ADU structures allows homeowners to create an additional source of income, as well as to make the value of property bigger.

While standard accessory dwelling units that are built anew on your property might take a long time to construct, prefab homes require less site work, which not only makes the whole process faster but also decreases the construction waste and lumber on your property. These tiny homes are manufactured in advance and delivered to your lot only for the final assembly.

Among other companies that provide shell ADU building services, ADU Builders Bay Area stands out with its professionalism and responsible take on every project. Once your prefab ADU is complete, we guarantee that you will be satisfied with the quality of the construction and all the monetary aspects of it.

Shell ADU Explained

Although standard ADUs are pretty popular nowadays, not everyone knows that they can be prefabricated as well. These buildings come as brand-new panelized construction, which can be of two sizes. The installation of windows, doors, and important utility connections, like electrical wiring, cooling system, heating, and plumbing, is made right on the site using the special kit that comes with exterior walls.

The construction company will install the foundation, wall panels, and roof, while the interior walls and design of the accessory house can be completed by the homeowner themselves if they want to save money. However, if you are willing to pay the contractor company for their professional services, the whole construction and interior design can be done by them as well.

The ADU tiny house is a complete living space that can be as small as 300 sq ft or as big as 800 sq ft. Depending on the preferences for the interior, such a prefab ADU can include its own bedroom, bathroom, kitchen, and other necessary areas, as well as energy-efficient utilities in all rooms. One can even incorporate such details as a walk-in closet or a bath into the original packaging of ADU in order to make the place as comfortable for living as possible.

The materials used for the exterior walls usually match the design of the primary housing unit so that your property looks harmonious from the outside. To achieve higher energy efficiency levels and a spacious feeling inside of the prefab ADU, windows and doors are added on the sunny sides. For those who live in hotter areas, prefab kits with cooling systems are developed as well.

To build a shell ADU on your lot, you will have to receive permits from the local authorities. Depending on the zoning regulations, your project might vary in size, distance from the main home, and the number of stories. ADU Builders Bay Area will deliver the best results by taking into account all of the details and specificities of your property.

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Shell ADU Construction Benefits 

Have you ever dreamt of your own backyard studio or a tiny house for your guests to stay in when they come over? Well, the cost of creating a prefab ADU for your property allows making these dreams come true easily. Such a unit will serve as a complete house, just of smaller sizes.

Prefab ADU kits have a lot of advantages for those homeowners who decide to install these structures on their property:

  • Saving money. As the whole foundation, including the wall panels, roof, windows, and doors, arrives in a ready-to-assemble state, the companies that you hire to install your prefab ADU reduce the cost that it would take to create the project from scratch. It allows you to save money not only on the construction work but also on the regular delivery of materials and some permits.
  • Durable materials. When it comes to shell ADU, the company manufacturing it makes sure that all of the panels, roof, and other structurally important details are made of high-quality materials that will serve you for long years to come. It also allows you to save money in the future, as no additional repairs or purchases of other materials would be needed.
  • Energy efficiency. In order for your shell ADU to be used in the most efficient ways, our ADU business makes sure that the most innovative techniques are used during the installation. With proper materials that provide heat insulation and a roof that allows homeowners to install solar panels, the cost of utility bills can be highly decreased.
  • Easy installation process. As the prefab ADU kits come with all the pre-made materials, the contractor company will complete the project in a shorter time, meaning you will get to enjoy your ADU as soon as possible. Once the assembly is complete, all that is left is to work on the interior by making proper bedroom and bathroom zones and installing heating, plumbing, and electrical systems for more comfort.
  • Personal design. The great thing about ADU kits is that they can be turned into anything, from a home studio to a personal cinema. With a customizable interior, you can match ADU with the primary housing or use other materials suitable for your purposes. This accessory house can be used as a home office or a guest house with an extra bedroom and bathroom for your guests to stay in.

However, in order for you to be able to enjoy these benefits, it is better to have the professionals install the kit. Otherwise, a small mistake in the construction might cause some future problems like heat leakage or, worse, crushing the whole structure. The safety of you and your loved ones should always be the priority, which is why having some specialists to control the whole process might be the best decision that you make.

The one company that will make sure your shell ADU kit is created and installed in the best way possible is ADU Builders Bay Area. By shipping the kit to your property and delivering other materials that are necessary for the construction, you will be able to save money on building the structure and allocate more budget on the interior design or efficiency improvements.


Shell ADU Business 

When it comes to hiring someone to create a shell ADU for you, it is important to pay attention to the experience and the scope of work that the company can provide. Here at ADU Builders Bay Area, we offer only quality services according to the latest trends in the construction industry. With a variety of skilled workers who specialize in different things, our business team delivers the most outstanding results and makes all of the customers happy.

Here are some of the reasons why you should choose our company for the development of your accessory dwelling unit:

  1. Our portfolio is full of successfully completed projects, including various types of installation of prefab ADUs.
  2. We have experienced professionals dealing with every step of the project, so you do not have to hire someone separately. Whether it is installing electrical and plumbing systems or securing the roof and the foundation, our team will make sure that each part is under control.
  3. Our work is more than just assembling the ADU kit. We always try to find ways to make the whole structure better and more convenient for the property owners to use.
  4. ADU Builders Bay Area team is ready to work on your project from start to finish. We not only assemble the kits but also provide you with developed interior design options and other recommendations throughout the whole process.
  5. Delivery of all the materials and construction equipment is done only by our team. You do not have to worry about paying some extra dollars for shipping services from outside.
  6. ADU Builders Bay Area makes sure that all of the time and budget frames are strictly complied with so that you get a brand-new ADU as soon as possible and with no unexpected costs.

Our team has worked on a variety of different projects, which gives us a lot of experience in the ADU construction industry. We take into account all of your wishes and preferences, as well as important property features, zoning regulations, and legal requirements for your area.

Contact ADU Builders Bay Area to start working on your shell ADU now. Create a nice little studio in your backyard or a guest house for your loved ones to stay. Or you can have a new rental income source built right on your property. With professionals at ADU Builders Bay Area, any kind of shell ADU can be created to satisfy your needs.

ADU Builders Bay Area is recognized by

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At ADU Builders Bay Area, we bring your construction visions to life. Our expertise lies in crafting ADUs, complete home renovations, and initiating new builds for both residential and commercial spaces. Our dedicated team prioritizes swift, accurate solutions customized to your requirements.

Our commitment to dependable craftsmanship, professionalism, and meticulous attention to detail is highly valued by our clients. Leveraging our deep industry experience, we efficiently address and resolve potential obstacles for seamless project completion. Proudly displaying our certifications and recognitions, we eagerly await the opportunity to collaborate with you on your next project.


Frequently Asked Questions — FAQ

What are shell ADUs?

Shell accessory dwelling units are prefabricated structures that come with a separate roof, foundation, and walls that are then installed into one piece right on your lot. Shell ADU kits also have doors and windows of the right size. Such ADUs are usually 300-800 sq ft in size, and they can be one or two-story buildings. Similarly to the standard ADUs, the prefab ones can be used as a living space for your friends and family, a personal studio or home office, or other entertainment purposes, like a home cinema or gym.

How to install a shell ADU kit?

A shell ADU kit is usually installed by professionals who make sure that each part is connected to the others securely. Shell ADU kit assembly includes not only the installation of the main structure but also the proper placement of doors and windows. What is more, a specialized ADU contractor will provide you with a good interior makeover and connection to the plumbing and electrical systems. Your shell accessory dwelling unit kit might include additional elements, like a loft, which also requires a professional take on it.

Are prefab homes more affordable?

If you compare a prefab structure with a standard accessory dwelling, you will be surprised to find out that the cost of building a shell ADU kit is much lower. It does not mean that prefab ADUs are worse in quality or use bad materials. Such a difference in price comes from the way of constructing an ADU itself. With shell ones, you get a delivery of different ADU parts right to your property, and then all that is left for the construction crew is to assemble it piece by piece. Therefore, a prefab accessory home allows you to save money in planning, receiving permits, and the building process.

What are the benefits of shell ADUs?

Having a shell ADU right next to your primary house allows you to add extra living space and functionality to some unused areas of your lot. The proper placement of doors and windows will help you to achieve higher levels of energy efficiency while still providing the tiny home with all the needed appliances. Moreover, if you are not planning to use the ADU for something like a studio or a home office, you can rent out the place and receive additional income from it. And if having other people so close to your home does not sound too comfortable for you, you can always turn the ADU into a guest house.

Can you assemble a prefab ADU yourself?

Although you can pay only for the manufacturing and delivery of shell ADU, it is highly recommended to have it installed by professionals. In order for the whole structure to be strong and sturdy, experienced construction workers should check if everything is done correctly during the assembly. What is more, a small mistake in the placement of walls or windows might cause bad insulation, which means you will have to pay more bills for heating.
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