The city of Seattle’s Department of Planning and Development first item in its list of proposed micro-housing legislation in Seattle is a legal definition of “micro” and “micro-housing,” as there is currently no distinction between micro-housing and other types of dwelling in the city code.  The proposed definition is as follows:

“Micro-housing” – means a format of multi-family housing in which the dwelling unit is composed of up to eight rooms each meeting the definition of a micro pursuant to SMC 23.84A.032.22, and with a common kitchen at least 120 square feet in size that is shared by each micro within the dwelling unit.


“Micro” – means a room or rooms within micro-housing and having all of the following characteristics:
a. contains 285 square feet or less;
b. contains a bathroom with a toilet, bathing facility, and sink;
c. does not contain a food preparation area or kitchen;
d. no sink is located outside of the bathroom within the micro”

How is the definition for micro-housing different from those of other types of housing?

The city’s proposal indicates that micro-housing currently falls under the regulation of simple households and simple dwelling units. Those are defined as follows:

“Household” means a housekeeping unit consisting of any number of related persons; eight or fewer non-related, non-transient persons; eight or fewer related and non-related non-transient persons, unless a grant of special or reasonable accommodation allows an additional number of persons.”


“Dwelling Unit” means a room or rooms located within a structure, designed, arranged, occupied or intended to be occupied by not more than one household as living accommodations independent from any other household. The existence of a food preparation area within the room or rooms shall be evidence of the existence of a dwelling unit.

The biggest differences between micro-housing and simple households under the proposed definition are the limitations placed on amenities. Individual units (or ‘micros’) cannot have some amenities you might find in studios, such as food-preparation areas or sinks outside the bathroom. Additionally, individual micros are limited in size. If the units are larger than 285 square feet then the building will not qualify as micro-housing.

What is the purpose of defining micro-housing?

The simple and short answer is that a definition allows the city to specifically regulate micro-housing in a different manner than it regulates other types of housing. This raises the most important question. Why do micro-housing units require different regulation than other types of housing, whether it’s a large house rented out to many tenants or an apartment building?

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Owen does servicing and consulting for a software company to pay the bills. He has an amateur interest in urban policy, focusing on housing. His primary mode is a bicycle but isn't ashamed of riding down the hill and taking the bus back up. Feel free to tweet at him: @pickovven.