The tiny house movement has been steadily gaining momentum in America and Michigan over the past few years because of the potential benefits that tiny homes can offer. Tiny houses are typically less than 400 square feet and can either be built onto a foundation or built on wheels. Because of their size and the fact that many do not have typical appliances, tiny houses provide an affordable housing option and a way for either single people or married couples to produce a smaller environmental footprint during the course of their day-to-day lives.

While a tiny house could be an excellent option for the right person, tiny houses sometimes lead to more questions than there are answers. For example, one of the biggest problems facing people who desire to live in a tiny house is not how to fit their possessions into the smaller space, but to find a place where they can legally build, and reside in, a tiny house. Most state and municipal legislators have not accounted for tiny houses because the tiny house movement is still relatively new.

While there are no statewide rules regulating where citizens can build tiny houses, the Michigan Zoning Enabling Act provides that each legislative body may establish zoning requirements that permit flexibility, innovation and variety for residential housing. This has led many municipalities in Michigan to provide minimum square footage requirements for residential dwellings, presumably to combat overcrowding and to ensure adequate housing. For tiny house owners, however, this means that they may be living illegally depending on where their house is located, how many people live in the house and the house’s total number of square feet. The legality of a tiny house may also depend on whether the house is a detached, independent structure or attached to a larger, principal structure. If it is attached to a larger structure, then it would fall under separate municipal requirements for accessory dwellings.

Even though most municipalities lack legislation regarding tiny houses, tiny houses will generally be subject to municipal zoning regulations if the municipality has a minimum square footage requirement for residential dwellings. The minimum requirements vary widely among municipalities, but most still have some minimum requirement. For example, the City of Grand Rapids requires that single family dwelling units must have a minimum gross floor area of 750 square feet. Ann Arbor, on the other hand, requires that every dwelling unit have at least 225 square feet of habitable room area. Other municipalities, like Lansing, do not provide any minimum square footage requirements for dwelling units, but provide minimum size requirements for property lots instead.

In addition to single family residences, many municipalities have different minimum size requirements for dwelling units labeled as “efficiency units.” Efficiency units are typically rooms in apartment complexes and have been defined as “any room having cooking facilities used for combined living, dining, and sleeping purposes” by the International Building Code. Michigan municipalities seem to treat efficiency units in the same way, defining them as a type of multiple-family or apartment unit consisting of one principal room plus a bathroom and kitchen facilities or a dwelling unit in which the bedroom is the only room. Some Michigan municipalities provide separate minimum square footage requirements for efficiency units while others do not make a distinction between independent dwelling units and efficiency units. For example, the Ann Arbor municipal code states that an efficiency unit must have 150 square feet of habitable room area for one occupant, with 100 additional square feet for each additional occupant. If a tiny house does not meet the municipality’s minimum size requirement, it may be able to qualify as an efficiency unit depending on whether the municipality has expressly defined what constitutes an efficiency unit. Unfortunately for tiny house owners, efficiency units are typically thought of as studio apartments and tiny houses probably would not qualify as efficiency units in most municipalities.

While most municipalities do not expressly provide for them, tiny houses will still be subject to municipal zoning ordinance requirements if the municipality imposes minimum size requirements for dwelling units. Tiny houses will have to comply with those requirements and those that do not will be illegal. Because most Michigan municipalities specify minimum dwelling unit sizes, it will be difficult for most tiny house owners to abide by the average municipality’s zoning ordinances. Tiny house owners may still have other options as they could still live in an established tiny house community. To date, there is one such community in Traverse City while others are being proposed elsewhere in Michigan. (Check out this Mlivearticle regarding tiny houses in Ann Arbor.) In most municipalities across Michigan, however, tiny house owners will generally not be able to avoid zoning ordinances and will have to comply with minimum square footage requirements.

Thomas K. Dillon