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Calculating the Costs of Accessory Dwelling Units | Building in Los Angeles

Updated: Feb 16, 2023

How to Calculate the Costs of Building ADU in Los Angeles

When it comes to building an accessory dwelling unit, the cost is perhaps the first question that hits your mind. Well, that’s a crucial question to think of. However, high chances are, you may not be an individual who’s acquainted in this field. Else, probably you don’t have an honest and reliable source of information. With this, it can be quite challenging to find out about the actual ADU cost as you plan for your Build and ADU project. It is for this reason that we have decided to assist you by bringing together a detailed breakdown of the standard ADU cost and how to calculate the cost of building one in Los Angeles. Read on to find out more about the costs involved when you decide to build a junior accessory dwelling unit (JADU), the things that determine the cost, and how to calculate the cost. First things first, what is an ADU? Well, merely put, it is a secondary living space in your home. Ordinarily, you can either attach an ADU to your house or detach it as a stand-alone unit. As a matter of fact, there are several types of ADUs. So, the cost of your project will vary based on the one you choose. The Cost of Constructing Accessory Dwelling Unit As a property owner that wants to construct a junior accessory dwelling unit, the obvious question regarding how much it will cost you to build one will always rise. While this is a legit question, countless sources give incorrect info about the cost involved in entirely constructing a JADU. First, you may come across a company that offers you a construction quote without envisioning the floor plans. In ideal situations, it is a major red flag that you need to be aware of when getting the estimates. All in all, the cost of constructing ADUs that measures approximately 400 by 800 sq ft with a living room, bathroom, kitchen, one bedroom, closet, and perhaps a space for a dryer and washer may have to part with about $70,000 to $80,000. What are the Factors that Determine the Cost? If you decide to detach the unit from your property, you’re eligible to get a separate address comprised of a panel box and separate meter, which you can use to handle two different utility bills. In most situations, when you think of the building’s design, a stand-alone can cost you up to $120,000 or even more. Another critical thing to note is that the floor plan designs and the used materials play a significant role in determining the ultimate construction costs. As you can see, these are the two vital factors that can fluctuate the costs of your ADUs. Honestly speaking, many factors play a part when it comes to Build and ADU projects. Additionally, various phases in ADUs constructions comprise of demolition, framing, foundation, plumbing, roofing, and electrical works. However, you will save the demolition costs if you are working on new structures, but you must include the foundation expenses. If it were a garage conversion with an existing foundation, on the other hand, you’d save the foundation expenses. Basically, you may notice the price of building the units varying from one customer to another since every client has different scenarios. Frankly speaking, new ADUs construction costs more than garage conversions as the existing garage structures lessen the required procedures. Nonetheless, if the condition of the existing garage is worse, you may need to demolish the whole structure and start from scratch. Here are the factors determining the cost of ADUs. Size As a general rule, the cost of building a 2000 square feet unit is higher than that of building 100 square feet. Thus, when calculating the projected cost of building ADUs, the constructor may give you the average cost by calculating the cost per sq ft. Nonetheless, if you are setting up colossal ADUs, the total cost may go down. Design While ADUs are smaller compared to your main house, it is essential to note that the design has an impact on the total construction cost. With this, get in touch with an experienced designer for an approximation of how much the plan will cost. An intricate design costs you a lot in terms of the used materials. Besides, the design comes down to the type of ADUs that you’re setting up. The main types of ADUs include:

  • Attached ADUs

  • Garage conversion ADUs

  • Detached new construction ADUs

Regulation Requirements Usually, the regulations and guidelines provided by the LA building and construction regulatory body may affect the ultimate construction cost. So, when estimating the costs, think of the regulatory expense that varies based on various aspects like type and size of the constructed ADUs. Engineering Review Cost The process of setting up ADUs in LA may sometimes demand the services of an Engineer. It is essential to determine whether the project will serve the intended purpose and assures the optimal maintenance and operational costs. To sum up, constructing ADUs is not only a huge decision but also a significant investment. Since the price varies based on the factors outlined above, you can lower the long-run costs by working with the right individuals, following the right steps, and making the perfect investment upfronts.



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