Architects and developers building across much of Seattle will soon have to meet the city’s new Mandatory Housing Affordability (MHA) requirements, a set of rules passed with a spate of recent comprehensive zoning changes designed to ensure that “new commercial and multifamily residential development contributes [new] affordable housing.”
The MHA regulations were approved this spring and are expected to add over 6,000 new low-income housing units to the city’s housing stock over the next decade. The changes are part of the city’s Housing Affordability and Living Agenda, a three-pronged effort undertaken by city agencies several years ago to increase housing supply in order to stem escalating rents and property values across the thriving region. The fiercely contested changes in land use will allow for a greater level of residential density in many of the city’s neighborhoods and will ask builders to either include affordable housing on-site or pay into a general fund that can be used by city agencies to create new affordable housing in other areas.
The new regulations span five categories of development density, from low-rise detached and row house neighborhoods to taller mixed-use districts where buildings will be allowed to rise to a height of 95 feet or more. The efforts will upzone roughly 6 percent of the city’s single-family zones. Single-family zones ultimately make up over 80 percent of the city’s residential areas.
MHA regulations, according to planning documents provided by the City of Seattle, will be pegged to the degree of upzoning that takes place: Under the plan, areas that have been upzoned most significantly will be required to add a relatively higher proportion of new affordable housing. The required fees administered in lieu of on-site affordable housing construction will start at $5.58 per square foot for projects located in low-rise areas outside downtown Seattle and will go as high as $35.75 per square foot for larger mixed-use developments, according to city agencies.
The requirements will necessarily affect the work of architects designing buildings in these areas, but it is so far unclear exactly how. The MHA requirements are set to go into effect immediately, as the city’s rezoning initiatives are approved on a neighborhood-by-neighborhood basis.