Seattle Companies Want to Drive Down Prohibitive ADU Costs

Legal barriers to accessory dwelling units may be disappearing in some places, but costs can still be prohibitive. Several companies are stepping forward with more affordable options.

1 minute read

November 25, 2019, 10:00 AM PST

By Philip Rojc @PhilipRojc


Accessory Dwelling Unit

Nicolás Boullosa / Flickr

In Seattle and elsewhere in the Pacific Northwest, ADU reform is moving forward at a decent clip. However, Natalie Bicknell writes, "adding a new dwelling unit, particularly if it is a detached accessory dwelling unit or DADU, is still an expensive and onerous process that can present insurmountable hurdles for many property owners."

Bicknell goes on, "An interesting fact about backyard cottages is that while they do tend to eventually rent for rates that are either at or below market value, in terms of square footage, backyard cottages are often the expensive type of housing to construct per square foot."

Why are DADUs so expensive? Because size often matters less than costs related to design, utility connection, construction, and permitting, which can drive prices into unworkable territory.

Bicknell goes on to discuss several Seattle-area companies offering to take care of those issues for potential ADU owners. According to one founder, several other tactics help reduce costs, including standardizing structures' corners and using raised foundations.

Wednesday, November 13, 2019 in The Urbanist

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I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching. Mary G., Urban Planner

I love the variety of courses, many practical, and all richly illustrated. They have inspired many ideas that I've applied in practice, and in my own teaching.

Mary G., Urban Planner

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