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Our experienced team drafts a detailed estimate, which we then finalize together to align with your vision and budget
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Sometimes, the existing living space in your main home is just not enough. When your family grows bigger over the years, adding an extra room to your house might be problematic. In the current state of the housing market, property owners can rarely afford to buy another home or apartment. Luckily, nowadays, homeowners can build in-law units called accessory dwelling units on their property.

An accessory dwelling unit is a structure that is located next to your primary residence. Building an ADU has become a popular trend among many homeowners, as those backyard cottages provide affordable housing and energy efficiency solutions. Whether you own a multi- or single-family home, the option of building an accessory dwelling unit on your lot is always available.

While there are several types of secondary units, some of the most financially efficient ones are prefab ADUs. Prefabricated accessory dwelling units provide additional living space that can be used as a studio or an extension to your main house. The great thing about prefab ADUs is that they require less time to be built. These tiny homes are usually assembled piece by piece right on your lot.

Adu Builders California is one of the leading prefab ADU companies. Our team of trained specialists will help you to develop an impeccable ADU project. From a prefab ADU design to construction and exterior finishes, Adu Builders California is ready to assist you all the way through. Read further if you are interested in prefab ADUs and the ways our company can help you with building one.

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ADUs Main Specs

Accessory dwelling units, shortly called ADUs, have recently become a staple for homeowners all over California. Having your own ADU means you get to have energy-efficient living space for any family member, guest, or tenant to reside. For those whose primary dwelling does not seem to be fitting anymore, a new ADU construction might be life-changing.

With plenty of options for interior finishes, you can also turn your ADU into a personal space for work, crafts, and other activities. These units allow you to have built-in storage and working space right outside of your main home. The days of long commutes to work and high prices for studio rentals are long gone. Now, you can easily save both your time and money.

Depending on what your lot allows, how much you want to spend on the project, and what materials you prefer, a certain type of ADU can be built. A prefab ADU is the best solution if you want to save money and create an additional living area on your property. Within a few weeks, Adu Builders California will plan, deliver, and assemble all the ADU pieces for you.

Prefab ADU Benefits

Prefab ADU construction brings many benefits to homeowners. Built off-site, these units not only provide more space but also increase your property value. If you get an ADU with the help of professionals, you can greatly improve your living situation.

Here are some other benefits that prefab ADUs can provide:

Building a new home from scratch will cost a lot of money. Although the base price varies for different projects, entire house construction will certainly be more expensive than getting an ADU. Adu Builders California offers plenty of affordable solutions to its customers, including prefabricated ADUs.

You can design an ADU with all the needed appliances and utilities just as you like it. Turning unused space on your lot into an additional living space will save you from big renovations in the main house. Also, you will not need to buy or rent any other property while still accommodating all your loved ones comfortably.

Prefab ADUs, unlike other secondary unit types, are much faster to build. These ADU models do not require a lot of site prep, as the construction crew only takes time to assemble all the premade pieces. Thus, the results of your ADU project will be delivered much quicker.

Even if you feel spacious in your primary residence, an ADU might be quite useful to have. You can rent out your property and receive some extra passive income regularly.

ADUs can give an advantage even for those house owners who like to think about their future in advance. Having an ADU in your backyard makes your property value higher on the housing market.

With Adu Builders California, you get to create an ADU that will serve any of your needs. Depending on the square foot number, you can turn your ADU into a home office, personal gym, guest house, creative studio, and more.


Prefab ADU Size Regulations

An accessory dwelling unit can have up to three bedrooms, according to the building codes. Although different state regulations might vary, depending on the area you live in, in general, an ADU studio can be quite big, especially if you are planning to have several stores.

However, there is another point to consider before creating a floor plan and obtaining permits. Granny flats can reach 16 feet in height at maximum. What is more, your ADU living space should be at least 150 square feet. When it comes to the maximum size, it cannot be bigger than 1,200 square feet. Even the minimum size is enough to have an ADU with a bedroom and all the needed facilities, so there should be no problems with the interior design.

Following this specific ADU ordinance, which is applicable in California, will provide you with an easy permitting process. Your local jurisdiction might impose some other requirements as well. That is why it is important to work with skilled specialists, such as the ones at Adu Builders California, to make sure that all the legal rules are considered before the construction.

Construction Preparation Tips

The Prefab ADU installation process is quite simple when you consider all of the obstacles in advance. To make all of your backyard cottage wishes come true, you can take steps to prepare your property for an ADU in advance.

Some general tips on how to make the whole process go smoothly include the following:

  1. Building a prefab ADU is easier if your lot has an even ground. Some families prefer to level their property beforehand to ensure that their ADU will stand properly on the ground. Another solution is to consider these plot specificities in advance and create an architectural plan according to them. However, such complications might increase the cost of the project.
  2. The assembly of ADU kits might get interrupted by excessive power lines going over your property. In California, local officials might refuse to permit the construction due to these obstacles. Think through all of this in advance or consult with Adu Builders California specialists to create an appropriate building plan.
  3. Another point to keep in mind is the width of your street. As mentioned, prefab ADUs will be delivered in different parts. However, they are quite big in size. Think about the possibility of cargo transport driving through the streets to your home, especially if they are narrow.
  4. Our workers will deliver your prefab kit right to your backyard. To do this without any problems, your driveway should be wide enough. Otherwise, our team will request a crane to transfer all the pieces on your lot.

Prefabricated ADU Types

When people hear about prefab living units, they often think about ADU plans with completely pre-designed interior and exterior elements and no possibility of adding something personal. Nevertheless, there are different ADU models that give you options for customizing your backyard home in some ways.

Modular ADUs

Such prefab units are the best when you need a quick installation and affordable cost. The general contractor receives an ADU from the factory in its almost complete state. It means that less work has to be done on your property.

A possible difficulty that might arise with this kind of ADU is the shipping. Because of their sizes, these units might be difficult to deliver to your single-family home. Another drawback is the predetermined floor plan. You will be able to design the interior however you like, but the overall floor plan usually cannot be changed. Still, ADU owners can always pick their own doors, floors, and roofing that will match the primary dwelling.

Those who are looking for affordable ADU cost and a fast construction process will find modular ADUs perfect for their homes.

Panelized ADUs

If you want to have a floor plan that is suitable for your lifestyle and fulfills some specific needs, go for a panelized ADU. These are prefabricated units as well; the only difference is that only the main parts, like walls and roof structure, are assembled in advance. Such an ADU might take more time to finish, but it gives you an opportunity to personalize your space as much as possible.

Panelized ADUs combine the affordability of cost and freedom of ADU design. Whether you want awning windows and sliding glass doors with plenty of natural light, built-in storage, energy-efficient solar panels, or an attached garage, everything is possible for these prefab units.

Focus on your own interior and create a perfect space with one bedroom or more. Compared to stick-built ADUs, this type of prefab unit will still cost less while giving you a variety of options to choose from.

Prefab ADU Cost

The thing that usually interests property owners the most is the total price of building an ADU. To tell the truth, each project usually has its own budget. It all depends on the number of square feet, materials chosen, installed appliances, interior plan, and difficulty of the overall process.

Sourcing materials is not something you should worry about, as Adu Builders California works with trusted providers. However, keep in mind that nowadays prices change frequently. The main point is to keep a clear budget plan. A good ADU builder will make sure that you have all the expenses explained.

In most cases, building a base is not that expensive. The cost of the project increases when it comes to choosing some finishing touches, like doors or roofing.

Comparing Prefab and Custom ADUs

In California, both prefab and custom ADUs are quite popular. Although previously, the main advantage of the custom ones was the availability of your personal floor plan, now even prefab ADUs give you such an opportunity.

Custom ADUs can be great if you want to add something unique to your unit. An extraordinary plan will cost more, but in the end, you will have the ADU that you have dreamed of. Moreover, if your lot has some specificities that do not allow a prefab ADU to be installed, custom units can really help.

When you think about it, both ADU kinds actually share the majority of advantages. Any ADU, whether custom or premade, provides energy efficiency, plenty of bedroom space, natural light, and all the utility connections. The affordability of building and maintaining your ADU in the future also makes this type of housing preferred by many people.

When choosing between prefabricated and custom units, pay attention to the overall costs. While building a custom ADU might be more expensive, the delivery of prefab ADU elements also adds greatly to the final price. In fact, budgets for both projects might turn out to be quite similar due to the shipment difficulties of prefab ADUs.

Adding a Prefab ADU to Your Property

There are several general stages of working on your prefab ADU:

  1. Get to know your contractor, their portfolio, and customer reviews. Adu Builders California provides its clients with all the information needed to make sure that our company is right for you.
  2. Plan some ideas to discuss with your ADU team. You can always take some inspiration from the portfolio or offer your own solutions.
  3. Prepare your lot for the upcoming construction work. Such preparation includes not only cleaning up the property but also having an ADU foundation ready. You might do it yourself or ask for the services of Adu Builders California specialists.
  4. Have our experts provide all the necessary utility connections. Adu Builders California workers will help you with providing water, electricity, gas, and any other facilities.
  5. Wait for the delivery of a premade unit. The large scale of shipping might cause difficulties, as you need to find a truck big enough to fit all the elements. Make sure that roads to your house actually allow big trucks to drive through.
  6. Install and assemble all the ADU pieces. Adu Builders California crew will do their best to construct your prefab unit quickly. To make sure that nothing interrupts the process, have a crane or rollers ready if your property is not big enough to let the truck unload freely.

With Adu Builders California, you do not have to worry about your prefab ADU at all. Each step of the process is under the control of skilled and experienced specialists. We are ready to assist you all the way through and answer all of your questions. Book a meeting with Adu Builders California now and order a new prefab ADU for your lot.

Frequently Asked Questions — FAQ

What is a prefab ADU?

A prefabricated ADU is a type of accessory dwelling unit. The main difference from the custom-made ones is that prefab unit elements are made in advance at a factory. A general contractor helps you to deliver all the pieces and then assemble an ADU right on your lot.

Does California allow prefab homes?

You can have a prefab tiny home in the State of California. Adu Builders California helps house owners all over the state to create ADUs of all kinds, including the prefab ones.

How much does an ADU cost in California?

The cost of having an ADU in California depends on the materials you choose, the square foot amount, and the complexity of the construction process. With Adu Builders California, you get reasonably priced housing solutions of great quality.

Valued Recognitions


Frequently Asked Questions — FAQ

What is an ADU?

ADU is an abbreviation for an accessory dwelling unit representing an additional secondary dwelling structure located close to the primary residence at the residential lot usually owned by one family. There are two main types of such structures, attached ADUs (resulting in the reconstruction of the existing inhouse space) and detached ADUs, which are the separate structures located on the premises territory. If you plan to build an ADU, you should find out the ADUs construction regulations established in your area. If the design of your attached or the detached ADUs conflicts with the design guidelines applicable for that of the primary residence, you won't be able to get the approval to perform the ADU building.

Can I cope with ADU construction myself?

ADU construction implies a lot of preparatory work. First of all, you should carefully learn the ADU building regulations established in your state. Secondly, the project design and all the cost calculations should be carried out. Thirdly, you must carry out the purchase of all the construction and decoration materials according to your cost estimate. Finally, the erection or reconstruction (in the case of the attached ADU) works should be performed. So, if you have enough expertise and experience in some areas of activity, you will be able to carry out the ADU all by yourself.

What is the price of ADU Construction?

The ADU construction costs are influenced by numerous factors, such as the type of your ADU (attached or detached), how many square feet your residential lot is, what size your potential ADU is planned to be, whether it will be a one-story or a two-story ADU, and many others. Generally, the ADU price tag can vary from 30 thousand to more than 300 thousand US dollars.

How long does it take to have the ADU built?

The average period of the new ADUs construction depends on whether you are going to erect a completely separated new accessory dwelling unit or reconstruct the already existing primary residential structure. As a rule, obtaining the building and reconstruction permits takes two weeks (the term may be increased in some cases), whereas the construction works themselves can take up to 4-To 6 months, depending on your ADU project
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