Washington Becomes First State to Allow Scissor Stairs in Multifamily Projects
In a move that could shift how developers finance tall, narrow-infill projects, Washington state lawmakers greenlit a building-code change permitting scissor stairs in multifamily buildings. The two interlocking exits, housed in a single fire-rated shaft, are designed to free up floor space and widen the options for dense urban sites. The policy was signed into law in March and takes effect June 11, a development that state officials say will unlock more units on constrained lots.
Washington now stands alone as the first state to authorize this design in multifamily construction, a step beyond the earlier push for single-stair reforms that target shorter buildings. For lenders and developers, the question is how the change translates into financing terms, risk, and the speed at which projects reach breaking ground in the Seattle metro area, where demand remains fierce and affordability a persistent headache.
What Scissor Stairs Are and Why They Matter for Financing
Scissor stairs consist of two escape paths that crisscross within a single, tightly enclosed shaft. By sharing a shaft, architects can reduce the overall building width needed for egress, which in turn preserves space for additional units, mechanicals, or communal amenities. Industry analysts say this can shrink hard construction costs and unlock previously unbuildable infill sites.
- Footprint savings: roughly 15% to 20% of the floor plate can be freed up for living units on certain layouts.
- Cost impact: estimates from builders and consultants point to mid-to-high single-digit to low-teens reductions as a share of hard costs, depending on project complexity.
- Permitting and schedule: some developers expect a 2-to-4-week acceleration in the path to permit approval and a faster overall construction timeline on tightly constrained sites.
- Unit yield: on some midrise sites, the space gained from scissor stairs can translate into 5 to 15 additional units in a six-to-eight-story building, depending on zoning and floor plates.
For lenders, the shift is not just about a clever layout. It matters for loan sizing, risk, and the structure of deal approvals. A smaller footprint can lower total project cost, which may improve debt-service coverage ratios and reduce the likelihood of draw-down delays caused by budget overruns.
Still, the benefits are project-specific. Analysts caution that the savings hinge on floor plans, corridor widths, and how the shared shaft is integrated with fire and life-safety systems. The Washington enactment comes with a testing ground: if actual projects prove the space savings and safety assumptions hold, banks will adjust pricing and underwriting accordingly.
Bankers Weigh In as Policy Rolls Out
Several lenders familiar with Seattle-area development credit say the change could meaningfully influence loan structures and pricing.
'We expect the policy to improve loan-to-cost by 2 to 4 percentage points in projects that can capitalize on the additional units and reduced footprint,' said Maria Chen, chief underwriter at Pacific Crescent Bank. 'That translates into more favorable debt-service coverage ratios and a larger buffer for contingencies, which is meaningful in a market still navigating rate volatility and construction delays.'
'Scissor stairs lower washington cost reductions could ultimately support higher loan-to-values on well-structured deals,' noted Jonathan Reed, director at Urban Equity Partners. 'But lenders will still insist on robust floor plans, standard fire-rating compliance, and clear procurement milestones before we adjust pricing or terms.'
Industry observers point to a two-track reality: the technical draw of the design is clear, but lenders need visible project-level data before committing to new underwriting scripts. Some banks are starting pilots on small-to-midsize projects to test how underwrites respond to the new geometry, while others are waiting for a broader sample of completed builds before re-pricing risk across portfolios.
Financial Implications for Developers and Lenders
The Washington move could create a more predictable cost curve for developers working in tight urban corridors. If the expected efficiencies hold, construction lenders may see a reduction in upfront reserves for contingencies and a tighter path to budget certainty—both of which can improve overall project economics.
In practical terms, lenders are watching several metrics closely:
- Debt service coverage ratios (DSCR) required by banks may edge lower on qualifying projects that prove shorter timelines and lower capex, potentially expanding the viable debt stack for a given project.
- Loan-to-value (LTV) thresholds could become more forgiving in well-structured deals that deliver more units in the same footprint, assuming no material shifts in market rent assumptions or cap rates.
- Underwriting timelines could shrink as design risk is reduced, but the safety case for life-safety compliance will still demand rigorous documentation.
- Borrowers may see improved terms on construction-to-permanent loans if the project demonstrates lower development risk and higher exit values.
Analysts estimate that scissor stairs lower washington costs could be particularly impactful on projects in the three-to-eight-story band, where the geometry problem is most acute and where space constraints often push developers toward suboptimal layouts. For a typical 60- to 80-unit midrise in Seattle’s urban core, savings could range from several hundred thousand dollars to several million, depending on unit mix and site geometry.
Timeline, Risk, and Next Steps
The policy’s effective date is June 11, and city planners expect early project proposals to reference scissor stairs as a core design feature on new builds. The building-code council has signaled that it will scrutinize early project data to validate safety and cost assumptions before further changes to residential egress rules are issued.
Industry groups expect a wave of proposals to surface in the coming months, particularly in Seattle, Bellevue, and Tacoma, where land scarcity and high land costs drive developers to maximize buildable area. Some developers may pursue a mix of scissor stairs with other efficiency strategies such as modular construction or value engineering to keep total budget in check as interest rates remain higher than pre-2022 levels.
Market Spotlight: Seattle and the Surrounding Region
Seattle’s housing market remains one of the nation’s most expensive, with developers facing tight zoning, scarce infill sites, and rising construction costs. The new scissor stairs capability could unlock more affordable unit counts on tight parcels, enabling projects that would have been challenged by width constraints alone. Local housing advocates say the policy directly targets the bottleneck that has long limited missing-middle housing on dense corridors.
However, the policy does not eliminate all cost pressures. Labor availability, material costs, and financing terms still influence project budgets and timelines. Banks and builders alike say the true test will be whether the predicted savings materialize across a broad set of projects and whether the life-safety certifications keep pace with design changes.
Bottom Line for Loans
Washington’s adoption of scissor stairs as a permissible feature in multifamily construction represents more than a design tweak. For the lending community, it introduces a new variable in underwriting that could lower upfront capex and improve unit economics, particularly on tight urban sites. If the savings prove durable, lenders may adjust risk appetites and pricing to reflect the enhanced project stability.
As the policy starts to flow through the financing pipeline, developers should prepare for a more nuanced underwriting process that weighs foot-print efficiency alongside standard life-safety and zoning reviews. In a market where every square foot and every permit cycle matters, scissor stairs lower washington costs could become a meaningful lever for getting more affordable homes built without sacrificing safety or quality.
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