Back in January, Council passed a resolution directing the Director of Planning to study the barriers to "micro-units" in Austin -- i.e., very small, efficiency apartments -- and to make recommendations for eliminating the barriers. My take was essentially that the City doesn't impose any meaningful size limit per se, but it does discourage small apartments through the Land Development Code's minimum site area requirements, which require a fixed amount of land per efficiency unit, no matter how small the unit.
Greg Guernsey, the Director of Planning, responded to the Council resolution this week. He noted that the zoning regulations do not set an explicit minimumsize. The building code does impose an effective minimum size (approximately 250 square feet), but that minimum is not a real obstacle to the development of micro-units in Austin:
Under the IBC [International Building Code], an efficiency must have 220 square feet of living area, with additional space required for a bathroom, making a feasible minimum space of approximately 250 square feet. For a one bedroom unit, the living area must be 120 square feet, with each additional habitable space at least 70 square feet, and additional space required for a bathroom. A one bedroom also requires approximately 250 square feet of space.
With most micro-units in the 300-350 square foot range, the IBC does not pose any real obstacle to the development of micro-units in Austin. Some municipalities, such as San Jose and Santa Barbara, have adopted local amendments to the IBC that allow the minimum size of an efficiency to be 150 square feet.
I haven't conducted a rigorous survey of recent infill development, but my impression, too, is that the IBC minimum doesn't really matter. If it were a binding constraint, we'd see units being built with around 250 square feet of floor space. But the smallest units I could find in the current wave of development are more than 100 square feet larger than that.
Guernsey instead identified two indirect barriers to micro-units: minimum site area requirements and parking.
Minimum site area requirements: Site area requirements specify the minimum amount of land required per dwelling unit. In Austin’s zoning code, these requirements differ depending on the zoning district. Site area requirements exist for most single-family and multifamily zoning districts, except for MF-6 zoning (highest density multifamily zoning district), DMU (Downtown Mixed Use) zoning, CBD (Central Business District) zoning, or through the utilization of the VMU (Vertical Mixed Use) combining district. Although there is no specified cap in density allowed in any zoning district, the minimum site area requirements effectively do as much. Under Austin’s current code, the smallest site area requirement is 800 square feet, for efficiency units located in MF-5 zoning.
Minimum site area requirements are an obvious culprit. They impose a high fixed cost per unit (the land cost) while simultaneously restricting the quantity of units. This incentivizes the construction of larger units. I pointed out that at least a couple of recent VMU projects on South Lamar (which are not subject to minimum site area requirements) have many more and likely smaller units than they'd have under the minimum site area requirement.
Guernsey also identified minimum parking requirements as a barrier:
Parking requirements: Minimum off-street parking requirements exist for all single-family and multifamily uses, depending on which zoning district they are located in. CBD and DMU districts do not have minimum parking requirements, and in Austin’s central core, the minimum parking requirements can be reduced by 20%, compared to land outside the core. In addition, the VMU combining district allows for a parking reduction compared to what would otherwise be required for that base zoning district to which VMU has been applied. Under today’s code, Austin’s multifamily use requires at least one space per dwelling, unless it meets one of the above conditions for reduced parking. That means that aside from CBD and DMU zoning districts, a multifamily development will have close to one parking spot per dwelling (at the 20% central core reduction) or more. This requirement for parking adds an additional cost per unit, and reduces density by requiring land for parking instead of additional dwelling units.
A parking space requires a minimum of 325 square feet or so (including space required for aisles and entrances), so it functions a lot like a minimum site area requirement. Plus, the fixed cost of building the parking space must be factored into the cost of the dwelling.
Guernsey identified the following ways to remove these constraints:
Minimum site area requirements: These requirements may be adjusted for urban core projects. In order to allow the kind of density typical of micro-unit developments, the site area requirements for multifamily zoning districts could be reduced or removed. As an alternative to adjusting the Code, micro-unit projects could request MF-6 zoning.
Parking requirements: Minimum parking requirements are appropriate for areas of Austin that are not well served by public transit or are lower density. Existing parking reductions and eliminations are a good way to allow the market to determine if parking is really necessary for a given development. To make the development of micro-units more feasible for property not zoned CBD or DMU (which is typically more expensive), parking minimums could be reduced or eliminated. A possible drawback to this, as has been experienced in Portland, is that tenants simply park their cars on adjacent neighborhood streets, much to the consternation of the people who live on those streets. One approach could be to couple any parking reduction with on-site car share (already incentivized in current code) or bike share facilities, or in conjunction with a residential permit parking program for adjacent neighborhoods.
Telling people to ask for MF-6 zoning doesn't seem to me to be a practical solution, if the goal is to encourage (or at least not discourage) micro-units. That ask requires a full-fledged zoning case, which is time-consuming, expensive and uncertain. That's a compelling strategy if you want to raise the average fixed cost of your units, not lower it. Developers, when they do ask for and receive MF-6 zoning, inevitably agree to all sorts of restrictions to limit the height and bulk of the development. That's fine, but it would make more sense to use the height and FAR limits already in place -- and there are different limits for each flavor of MF zoning -- rather than require a bunch of ad hoc negotiation.
Reducing parking could also help. As I've pointed out before, the existing parking minimums might not matter for the developers of the large VMU projects. (I must caveat this, again, by acknowledging that I haven't done a systematic survey.) But there are many smaller sites on our core transit corridors which might be developable only with reduced parking. I suspect we'll find out as developers work their way through the choicer sites.
