The benefits of an Accessory Dwelling Unit - ADU
One of the most popular home improvement projects are ADUs. There are many forms of ADUs:
Detached separate unit without common walls to the main house structure. Common terms for these are Granny Flats and Cottages.
Garage Conversions is simply where you convert one or more of your garage spaces into living space.
Addition (added space to the current home) or Second Story Addition
Conversion of a portion of the internal space of the home
Why are ADUs so popular especially in California? California has experienced a housing shortage since the 70s. Population growth in the state has passed the supply of housing units produced by homebuilders. Approval processes, red tape, and growth restrictions have contributed to the slowing of building. Until recently the California and local municipalities have become more favorable and looked to use existing Single Family lots to help alleviate the shortage. New relaxed zoning and setback requirements have allowed structures/additions to fit on a majority of existing single-family lots.
What are the benefits of an ADU and what is their use? Originally when the traditional Granny Flat was developed most Homeowners would use the extra space for Storage or Au pair. Today most units are specifically designed and developed for intended use – Rental Income, Adult Children or Aging Parents, Short Term Rentals, Live-in Health Care, Owner Downsizing (renting of the main house and living in the ADU), Added Home Value (new square footage added to the existing homes square footage and used for new appraised value – resale).
Kit or Pre-Assembled ADU’s vs Custom Built ADU
Kit or Pre-Assembled - One of the most popular and marketed forms of ADUs are Kit/Pre-Assembled forms. These units are usually pre-built or produced in a factory and then trucked to the site and lifted into place. The utilities (electrical, water, sewer, and cable) connections are not usually included in the Kit/Pre-Assembled marketed cost for the installation of a new ADU. The utility connections cost can sometimes be 30% to 50% of the cost of the pre-built unit. Permit Fees and School fees will also need to be added to the cost of the pre-built unit.
Custom Built – Has many advantages over the Kit/Pre-Assembled products.
Custom Designed for your Specific Lot. This includes Layout on your specific lot and can be designed to fit non-standard lots (triangled lots, flag lots, pie-shaped lots, elongated or deep lots)
ADU exterior matching or complementing the main house. A majority of Kit or Pre-Assembled ADUs have boxy or square designs so that it can be built less expensive and transported on highways. The Custom option can be built with exactly the same materials as the main house. In the East Bay, where I build, most homes are not square or rectangular boxes, they have certain styles – Rancher, Spanish, French, or English style roof pitches, stucco, or stone exteriors. Most Kits or Pre Assembled options will have no or little architectural style. Building an ADU that matches the main house will look aesthetically better and complement the main house, look like it was built at the same time as the main house, and increase the home’s resale value.
Custom interior finishes selected by the Homeowner. There are 1000’s of products to select from, from Plumbing or Electrical Fixtures, Appliances, Cabinets, and Counters. Building Custom allows you the Homeowner to select each individual product for the ADU. In many cases, Homeowners will upgrade the main house Appliances or Fixtures and use the older fixtures for the new ADU.
Custom design layout. Designing a floorplan layout for your exact intended use is one of the best advantages. Maybe you need a workout room with specific measurements to fit equipment? Would you like a laundry room? How about an additional bathroom? Home office along with an additional bedroom? Or maybe you need a large storage area included in your new unit? Kit or Pre-Assembled are limited in their designs. They have very standard items and very few optional or customizable spaces.
Custom ADU will be more expensive? Yes, in some cases, but not significantly. Both Kit/Pre-Assembled and Custom projects require services to the units – Electricity, Cable, Sewer, and Water. These will be equal in most cases, however, a custom project will have the option to design the location in the building where the services will tie in. The Custom option service tie-in will be cheaper. Both options will also have to pay for a Building Permit, School Fees, and any other City or County Fees. So how much does an ADU cost? Research from the UC Berkeley Center for Community Innovation found that the average cost to construct an ADU in California is $250 per square foot.
What would you rather look at? Building shelter for people is what I do for a living. The number one factor that separates an average project from a great project is how the project integrates into the surrounding area. Basically, does it fit? I have yet to find a Kit/Pre-Assembled ADU that does this.
