Accessory dwelling units (ADUs) have been a source of spirited conversations in the Bellingham building community for the past few years, and for good reason. In 2023 City of Bellingham revised its rules for ADUs in single-family zones city-wide by simplifying the permitting process. We’re big advocates of ADUs and are hopeful that more folks in Bellingham will consider adding an ADU to their existing single-family home.
An ADU is a small, self-contained residential unit on the same property as a single-family home. These units have the basic facilities necessary for day-to-day living including a kitchen, sleeping area, bathroom, and separate entrance. They can be a separate unit within the home (such as a basement), an addition to the home, or in some instances a standalone structure on the lot. The only difference between a DADU and an ADU is that DADUs are detached from the main dwelling (DADU=Detached ADU). Folks often refer to ADUs and DADUs collectively as ADUs.
The 2023 ordinance significantly expanded ADU possibilities in the City of Bellingham. Here are a few high points. We recommend referring to the City’s ordinance and discussing your specific project with the planning department for a full list of requirements:
- Limit of 2 ADUs, plus the single-family unit – for a max of 3 buildings per lot.
- Owner occupancy in one of the units is only required in areas zoned “residential.”
- Size limit of 1000 square feet.
How much does an ADU cost to build?
Three main factors make up the cost of any building project: the scope of work, permitting and utility connection costs, and the cost of construction. With ADUs, the decision that impacts the final cost the most is whether you opt for an ADU or DADU.
Even though ADUs are smaller than full-sized homes, they are equally complex. As with all building projects at Chuckanut Builders, ADUs require a designer. We recommend seeking out a designer who is experienced in designing compact spaces as they will know how to best utilize small spaces. We’re happy to point you toward a few great designers we regularly work with and trust!
It’s important to recognize that ADUs squeeze all the functions of a full-sized home into a much smaller footprint. Final costs can vary significantly depending on the design, material choices, construction methods, and site conditions. Generally speaking, we have found that a high-quality, 800 square foot ADU, with durable finishes, starts around $350,000.
Are you ready to start planning your ADU? We’d suggest reviewing the and chatting with the City Planning department. We’re always happy to schedule a site visit and recommend a building designer experienced with ADUs. We’re excited to do our part to increase housing options in Bellingham and hope to talk to you soon about your project!
by Intellitonic