Can I Build an ADU or Basement Apartment in Herriman, Utah?
Hi, Caleb Dansie here with Dansie Design Build. Today I want to consider what it takes to prepare a home for an Accessory Dwelling Apartment, Basement Apartment, or Accessory Dwelling Unit (ADU). Within Herriman City, there are five important things to consider before taking any steps. Meeting these five requirements help ensure that your project will meet all the city requirements.
Zoning defines what is and is not permissible to build on a property within the city. Herriman City only allows ADU’s on agricultural and residential zones. The lot size must also be 6,000 square feet or larger. That’s roughly 0.13 acres. The existing structure must be a single family home as well. Those are the zoning requirements that we must meet.
The City of Herriman requires that you have four parking stalls for a residential home, which includes the garage. If you have a two car garage, that counts as two parking spaces. In this instance, two more parking spaces are required in the driveway outside of the garage. This allows for four available parking stalls or spaces and meets the requirements of the city. When adding an ADU, one of those stalls may account for the basement tenants. If, however, your home only has a single car garage and a single parking space in the driveway, the ADU downstairs necessitates adding two more parking stalls.
Basement Entry Access
The next thing we need to look at is the actual entry into the basement. We frequently use the interior basement entrance to access the basement apartment. Adding a basement walkout, however, creates convenient access and is allowed by the City so long as it is located on the rear or side of the house.
Once we’ve decided on these previous items, we can discuss the actual basement work. This includes the layout. Helpful Tip: Planning the floor plan around the existing plumbing is most economical. We specifically plan around the ABS waste drain pipe that leads to the sewer or septic. There is a vertical “plumbing stack” that the upstairs plumbing fixtures drain through into the under-slab drain pipe. The location of that stack is the ideal area to install a nearby kitchen sink.
The bathrooms are also key to layout. Many times, bathrooms are already stubbed out and prepared to accept the wastewater drainage. This simplifies things, therefore, we like to use that space for the bathroom.
Plumbing for Basement Appliances
The washer and dryer hookups also revolve around the plumbing. Those easily fit well near the kitchen sink or a bathroom. Sometimes we can install them on the backside of a bathroom or kitchen wall if there’s an interior practitioner wall. If not, we can run some drainage piping in the exterior wall framing to tie in those wastewater drain lines from the washing machine.
Basement Bedroom and Living Room Egress Requirements
The next step to consider is the locations of the bedrooms and living rooms. All bedrooms are required to have an egress window. The requirements for an egress window are a 22 inch wide window opening, a minimum 20 inch tall opening, and a total opening that equals four square feet. 22×20 inches does not equal four square feet, but those are the minimum vertical and horizontal requirements. A total of four square feet of area is required for a person to evacuate in case of emergency.
The window well outside of those egress windows must be large enough for a person to stand up and evacuate. The City requires that each window well have a minimum of nine square feet on the footprint of the window well, 36 inches from the exterior wall to the farthest point of the window well, and a ladder so the individual can climb up and out to evacuate.
Five Steps to Plan Your Basement ADU Remodel in Herriman, Utah
Once we’ve looked at these five steps: 1. Zoning, 2. Parking, 3. Basement Entry, 4. Plumbing Layout, and 5. Egress Requirements, we will have a good idea if we can convert your basement into an ADU/apartment.
How to Finish Your Basement or Convert to a Basement Apartment Unit
If you have further questions about basement finishing or if you’d like to turn your basement into an apartment in Herriman or the surrounding areas, reach out to us on and schedule a consultation. We’d love to meet with you. I hope you enjoyed this video and have a wonderful rest of your day.