Small Subdivisions & Pipestem Lots

Background: One of the recommendations in Sumner’s Housing Action Plan is to increase the number of single-family lots that can be created through short subdivisions and pipestem lot subdivisions. Land can be subdivided either in a “full subdivision” process (for 5 or more lots) or a “short subdivision” (4 lots or less). A full subdivision process is much more complex, lengthy and costly than a short subdivision process. Requiring the full subdivision process for a small development (e.g. 6-7 lots) can be a barrier to housing infill. Pipestem lots (flag-shaped lots) are created through the same subdivision process as other lots. However, current code limits these to 1 additional lot behind the main house, which is also a barrier to infill development. Code changes are intended to increase flexibility for smaller sites, make small housing projects more feasible, reduce costs for infill housing, and to help address needed housing capacity.

What’s in the new code:

The code update would allow more single-family lots to be created in a streamlined permitting process. Proposed regulations include:

• Allowing a short subdivision process instead of a full subdivision for up to 9 lots (instead of 4 lots), and allowing pipestem lot subdivisions to have up to 4 lots (instead of 2 lots).
• Creating narrower access standards to allow a shared driveway for up to 5 dwellings and a 25-foot wide private drive aisle for up to 9 dwellings.
• Allowing pipestem lot size to be the same as other lots in the zone, allowing building height to be the same as the zone, and adjusting pipestem lot setbacks.
• Setting a maximum lot size for single-family homes built in multifamily zones. This will reserve land in Medium-Density and High-Density Residential zones for more dense single-family infill and multifamily development, which is the original purpose of the zones.
• No change in the density already allowed in each zone; the code just makes it easier to create housing.

The proposal will be reviewed by the Planning Commission and City Council. Opportunities for public comment on the proposal during the review process will be posted on this webpage.

What's happening

April 2023 Update

The City Council adopted the proposed ordinance as written, at their April 17, 2023 meeting. The final ordinance is posted in the documents column on the right.

March 2023 Update

The Planning Commission recommended a few changes to the proposed regulations for pipestem lots. They will discuss the draft regulations again at their March 2 meeting.

January-February 2023 Update

The Planning Commission reviewed the draft regulations at their December 2022 meeting. They will hold a public hearing on this on February 2, 2023. The Commission may take action on the regulations following the public hearing. More details can be found in the documents posted in the column to the right.