Summit Law Blog

HB 1096 and SB 5559 represent key steps toward increasing housing supply in Washington. HB 1096 requires local jurisdictions to establish a process for administrative lot splitting, while SB 5559 outlines procedures for unit lot subdivisions. Together, these laws lay the foundation for more flexible and affordable housing options across the state.

What Does HB 1096 Do?

HB 1096 introduces a new provision to RCW 58.17 that sets specific conditions under which local jurisdictions must approve administrative lot splits. Lot splitting is the process of dividing a single piece of land into two or smaller lots for sale, lease, or building development. It’s a way to increase housing supply by increasing the number of buildable lots from a single parcel. Local jurisdictions are required to allow the same number of housing units on each newly created lot as were permitted on the original lot. Both the original and newly created lots must comply with the applicable minimum lot size and density requirements of the jurisdiction.

What Does SB 5559 Do?

SB 5559 builds upon HB 1096 by establishing a framework and timelines for the review and processing of unit lot subdivisions. Specifically, the legislation requires that:

• No public pre-decision meetings or hearings may be required, nor any non-administrative design review.
• Only clear and objective design and development standards may be applied.
• The process must be logically integrated with the existing application, review, and procedures for the original lot, to the greatest extent feasible.
• The procedures must be subject to the same maximum time period that applies to other local government actions.

When Must Local Jurisdictions Implement HB 1096 and SB 5559?

Local jurisdictions that are required to update their Growth Management Act (GMA) periodic update in 2027 must implement HB 1096 and SB 5559 with that update. All other GMA jurisdictions must implement HB 1096 and SB 5559 by July 27, 2027, which is two years after the law’s effective date.

Why HB 1096 and SB 5559 Matter

Together, HB 1096 and SB 5559 are designed to simplify and accelerate the process of subdividing residential lots and building new homes across Washington. By simplifying the lot-splitting process and streamlining the approval process for unit lot subdivisions, these laws pave the way for a more predictable and streamlined path for building smaller, more affordable homes.