Micro-Housing Legislation Needs Work

Background

Marion Micro Housing by Neiman Taber

In response to the ongoing controversy over micro housing, Councilmember Mike O'Brien has proposed new legislation that would significantly change the rules for micro housing development in Seattle.

Depending on your point of view this proposal is either a welcome reset of the development standards for the zone, or a step backwards in terms of accommodating the real world needs of our housing market.  Putting this question aside, the proposal is based on the premise that current forms of micro housing have a unit density that is inappropriate (too dense) for the low-rise (LR) zones.

Ravenna Micro Housing by Neiman Taber

Current micro housing development is mostly built in the form of congregate housing (private sleeping rooms with shared kitchens and other amenities) and produces an average unit size of about 150 ft.². Councilmember O'Brien's proposal would ban private development of congregate housing in LR zones, replacing them with conventional studio apartments with a minimum average size of 220 ft.². Development under this new proposal would result in a unit density roughly two-thirds of what is typical today.

Land-use regulations should always be as simple and as flexible as possible. Since the purpose of the proposal is to limit density, the straightforward way to do so is to impose a density limit. Instead, the proposal attempts to regulate density indirectly by restricting unit type, size, and features in a manner that is unnecessarily restrictive, complex, and likely to lead to unintended consequences.

As architects that specialize in infill housing we have designed a number of small unit housing projects. Some of the projects are congregate style micro housing with shared communal spaces. Some of the projects are conventional studio apartments that have few shared amenities. While these two types of small unit housing serve a similar sector of the housing market, the unit designs for the two types are quite distinct from one another and neither type matches very well with the unit sizes that are anticipated by the new proposal.

The Difference Between Micros and Studios

Small studios and micros are not the same thing. Micros are generally designed with built-in amenities along the perimeter of the room and a walkway down the middle. Studios are generally designed with bathrooms & kitchen areas clustered into a zone so that the remaining living room area can be set up with loose furniture arrangements.

Because of their efficient configuration, micros generally average around 150sf (Figure 1a).  As they get bigger, the built-in amenities get roomier, resulting in larger bathrooms, kitchenettes, desks, and beds. In all sizes, a double loaded walkway down the middle remains more or less a constant (Figure 1b).

Because of the pragmatics of furniture settings (and a code dictated minimum living room size), most studios are larger than 220sf (Figure 2a).  In our projects, it is rare for us to design studio smaller than 250sf.  As studios get smaller, they get progressively more difficult to furnish in a useful manner (Figure 2b).  220sf is very close to the lower limit for a studio. 

So, while it is quite possible to design a useful dwelling unit at 220sf, or even 180sf (the minimum size currently proposed), the low end of the range anticipated by the proposal is not realistic in the studio format.

The floor plan arrangement that works best at that size is the one we use for micro’s, but this kind of floor plan cannot meet the minimum living room area required for studio apartments (currently 150sf, proposed 120sf).

Conclusion

The legislation, as proposed, would make it impossible to provide a small unit in the format that makes it most useful for the end user.

If the goal is to regulate density, then regulate density.  Council member O’Brien’s proposal would work out to roughly a density limit of 1/150 in LR3 and 1/230 in LR2 (units /land sf).  LR1 already has a density limit for apartments.

Enacting a density limit would achieve the council's stated policy goals while making large parts of the remaining legislation unnecessary.  With a density limit in place, there is no need to regulate minimum unit size, both small apartments and congregate housing could be allowed, and there is no need for the land use code to micromanage the interior design of housing units.  The outcome is predictable, flexibility is preserved, and individual developers and architects remain able to design housing that best fits the needs of users.

Table A for 23.45.512: Density Limits in Lowrise Zones

Zone	Units allowed per square foot of lot area by category of residential use
	Cottage Housing Development (1) and Single-family Dwelling Unit	Rowhouse Development	Townhouse Development (2)	Apartment (3)
LR1	1/1,600	No limit	1/2,200 or 1/1,600	1/2,000
LR2	1/1,600	No limit	1/1,600 or No limit	1/1,200 or No limit 1/230
LR3	1/1,600	No limit	1/1,600 or No limit	1/800 or No limit 1/150