Washington state is tackling multifamily construction costs through a less-discussed but practical avenue: scissor stairs. This building code change allows developers to use a single shared stairwell configuration instead of requiring separate exit stairs for each unit. The shift follows single-stair reform that has already gained traction across state legislatures and city halls as a tool to unlock missing-middle housing.
Scissor stairs reduce construction expenses by eliminating redundant stairwells, a major cost driver in mid-rise apartment buildings. The configuration uses one staircase that serves alternating floors, effectively doubling efficiency without compromising fire safety or building code compliance. For developers, this translates to lower per-unit construction costs and faster project timelines.
The impact flows directly to market participants. Builders can reduce the square footage devoted to vertical circulation, freeing up usable units or reducing overall building footprints. Reduced construction budgets make projects pencil out in secondary markets where land costs are lower but construction expenses remain high. This particularly benefits the missing-middle segment, where 4-8 story buildings serve households earning 60-120% of area median income.
Renters benefit through lower development costs pushing toward more affordable unit pricing. Landlords gain economics that improve project viability for new construction. Lenders see reduced risk profiles as building budgets tighten, potentially lowering development financing costs.
The change represents the unglamorous but effective side of housing policy. Zoning reform captures headlines, but technical building code adjustments address real construction barriers. Washington state's scissor stair approval joins other states recognizing that fire-safe, cost-reducing code changes expand housing supply without requiring politically contentious zoning overhauls.
This approach works particularly well for the 5-7 story market segment where construction costs per unit remain stubbornly high despite strong demand for affordable rentals.