The 4800 Overlay District

zoning In the last post we looked at the City's first cottage housing project which provides for more housing options for people who may want a smaller single family residence but also enjoy the lower maintenance and community aspect of clustered housing. In this post we'll discuss another housing option that became possible when the City passed the 2008 housing options ordinance, the 4800 overlay district.

Areas of the cities that are zoned for single family residential (i.e. 1 lot, 1 house) are often referred to by the minimum lot size in square feet. Mountlake Terrace has two single family (or single household) zoning designations, RS 7200 and RS 8400. In general, existing lots in these areas are at least 7,200 SF and 8,400 SF. Any new development in these areas would also require that lots be at least this size.

The 4800 overlay district is an area within the RS 7200 zone mostly surrounding the Town Center (BC/D). Redevelopment of properties in the 4800 overlay district allow single family lots as small as 4,800 square feet.

The City Code gives 5 reasons for the overlay district:

  1. Provides opportunities for new detached homes
  2. Increases neighborhood walkability and pedestrian orientation
  3. Reflects the interest of many families in having somewhat smaller lots to maintain
  4. Increases options for market-rate affordable housing
  5. Encourages quality redevelopment where appropriate

If you do the math you will notice that an owner of a single existing single family lot would likely not be able to subdivide to create two 4,800 sf lots. Most of the existing lots are just over 7,200 sf which would result in two 3,600 sf lots, smaller than the required 4,800 sf. But, if someone owned two adjacent 7,200+ sf (2 x 7,200 = 14,400 sf) they could subdivide those two lots into three 4,800 sf lots (14,400/3 = 4,800 sf).

There are some additional design requirements for the smaller lots to encourage more walkable, attractive, and pedestrian-oriented neighborhoods. The City Council is scheduled to revisit the subdivision code this year which will hopefully result in incorporating these design requirements in to all single family residential development. Some examples of these are requiring adjacent homes to have different floor plans to avoid a "cookie cutter" look, limiting the garage area on the front of the house and requiring transparent windows to encourage community interaction and security that includes “eyes on the street”, and encouraging the use of shared driveways to reduce stormwater runoff and curb cuts in the sidewalks.

The City has yet to have any developers take advantage of the ability to develop smaller lots but I see several reasons why that will likely change soon.

The way households are going to be evolving over the next few decades is toward more singles, empty-nesters, and city-lovers, none of whom particularly want the big yards and long commutes they may have grown up with as kids.  A significant market for those things will still exist, but it will be a smaller portion of overall housing demand than it used to be.  This new reality means that the communities and businesses that take account of these emerging preferences for smaller homes and lots and more walkable neighborhoods will be the ones that are most successful.

  • With the minimal development and changes we have seen to the Town Center neighborhood, it's already becoming a much more desirable place to live. There is plenty of land available for new multifamily housing in the Town Center but the number of single family homes within walking distance is limited. Options like small lot and cottage housing will allow an increase in single family housing.
  • Most of the homes in the 4800 overlay district were built in the 1950's. Homes that have been well taken care of can certainly last for many more decades but most of the concrete block homes in the neighborhood were built quickly and on the cheap. It is going to increasingly make more sense to tear down these old homes and rebuild rather than continue to continue to spend money upgrading.


A Patchwork of Nodes

City's First Cottage Housing Development Breaks Ground