Introduced by Senator Scott Wiener on February 21, 2025, Senate Bill 677 marks a significant effort to combat California's severe housing crisis. This proposed legislation aims to strengthen two key housing laws—SB 9 and SB 423—by tackling implementation hurdles, cutting red tape, and ultimately making it faster and easier to build needed homes. As a key component of a broader strategy to boost housing supply statewide, SB 677 seeks to unlock development and improve affordability across California.

The Housing Crisis and Past Legislative Efforts

California is experiencing an extreme housing deficit, with an estimated shortage of 2.5 million homes. Approximately 200,000 residents are homeless, and about 80% of low-income families in the state are paying more for rent than they can financially sustain.

In response, lawmakers have passed a series of high-profile housing reforms:

• SB 9 (2021): Effectively ended single-family zoning by allowing homeowners to split single-family lots and build duplexes—a major change aimed at increasing gentle density.
• SB 35/423 (2023): Established streamlined approval processes for multi-family housing in cities failing to meet state-mandated housing production goals.

While these laws held promise, they've struggled in practice:

• SB 9 applications have been sparse: San Francisco received just 32, San Jose 37, and Oakland only five. In contrast, San Francisco received over 460 Accessory Dwelling Unit (ADU) applications during the same period.
• SB 35/423 progress has been slowed by burdensome affordability mandates and infrequent housing need assessments.

What Is SB 677?

SB 677 functions as a targeted "clean-up" bill, designed to refine and bolster SB 9 and SB 423. It addresses known loopholes and bottlenecks that have hindered these landmark laws from achieving their full potential.

The bill concentrates on two primary areas:

• SB 9 Enhancements: Refining rules for duplexes and lot splits.
• SB 423/35 Improvements: Making streamlining for multi-family housing more effective.

Together, these updates aim to overcome local regulatory barriers, reduce bureaucracy, and accelerate new home construction in urban and suburban neighborhoods.

Key Updates to SB 9

SB 9 intended to expand gentle density, but practical hurdles have limited its use. SB 677 targets several significant barriers:

• Elimination of Owner-Occupancy Requirements
  Removes the mandate that homeowners live on the property for three years after a lot split – a condition often called SB 9's "poison pill" due to its limiting effect.
• Preemption of HOA Restrictions
  Prevents homeowners associations (HOAs) and private covenants from blocking SB 9 projects, opening up development potential in many restricted suburban areas.
• Increased Unit Size Flexibility
  Proposes increasing the ministerial approval size limit from 800 to 1,750 square feet, allowing for more livable homes suitable for families and capable of generating meaningful rental income.
• Disaster Recovery Exceptions
  Allows SB 9 projects on sites where existing rental housing was damaged or destroyed in a natural disaster, aiding community rebuilding with resilient housing.
• Curbing Local "Poison Pills"
  Aims to limit local government practices that can obstruct SB 9 projects by:
  • Prohibiting cities from adding extra affordability requirements.
  • Banning arbitrary dimensional standards hindering development.
  • Restricting excessive impact fees.
  • Requiring SB 9 projects receive treatment equal to other by-right zoning uses.
• Streamlined Applications
  Introduces a single, combined application form for housing development and lot splits, reviewed concurrently to save time, money, and reduce confusion.

Key Updates to SB 423 / SB 35

While SB 423 has facilitated some housing, developers face practical and financial hurdles. SB 677 addresses these:

• More Feasible Inclusionary Requirements
  For streamlined market-rate projects in cities not meeting low-income housing goals, the bill adjusts the required affordable housing share from 50% down to 20%, improving project viability while still supporting affordability.
• Faster Housing Need Assessments
  Mandates housing needs assessments every two years instead of four, activating streamlining provisions sooner when cities lag in housing production.
• Reversing the Burden of Proof
  Local governments challenging a project's eligibility based on environmental factors would now need to provide substantial evidence supporting their claim, preventing potential misuse of environmental laws to block housing.

Benefits for Homeowners

SB 677 offers California homeowners new opportunities to utilize their property:

• Gain More Flexibility
  Removing owner-occupancy rules and HOA bans empowers more homeowners to pursue small-scale development and generate rental income.
• Build More Valuable Units
  A higher square footage limit allows for more spacious units attractive to families and commanding potentially higher rents.
• Experience Simpler Permitting
  A unified application process aims to make approvals easier and faster to navigate.
• Rebuild More Easily After Disaster
  Homeowners facing rebuilding can utilize SB 9 with greater flexibility, potentially improving financial recovery.

Part of a Larger Legislative Push

SB 677 is one of roughly 20 bills in California's "Fast Track Housing" legislative package – an ambitious, bipartisan effort to increase efficiency throughout the development process.

Other notable bills in the package include:

• AB 557: Aims to speed up permitting for factory-built housing, potentially reducing construction timelines significantly.
• AB 609 (Wicks): Aims to exempt certain infill projects meeting existing zoning and environmental standards from CEQA review—potentially representing significant CEQA reform.
• AB 712: Proposes penalties for agencies failing to comply with housing statutes.

Collectively, these measures form a comprehensive strategy to address California's housing crisis.

Current Status and Support

As of March 29, 2025, SB 677 is progressing through the legislative process and is under consideration by the relevant Senate Committees (typically Housing and Local Government). Authored by Senator Scott Wiener with Assemblymember Buffy Wicks as co-author, the bill has garnered significant support from major housing advocacy organizations, including:

• California YIMBY
• Housing Action Coalition
• LISC San Diego

California YIMBY has launched a petition to demonstrate public support and build momentum for the bill.

Analysis and Outlook

SB 677 directly confronts some of the key weaknesses identified in California's earlier housing legislation. Research highlights the potential impact: the American Enterprise Institute (AEI) estimated that allowing four units by right on residential parcels could generate an additional 90,000 housing units annually. Yet, as AEI researcher Tobias Peters cautioned regarding barriers, "If there are a hundred things that could stop this thing from taking off, and you clean up 99 but leave one in place—nothing is going to happen."

SB 677 attempts to remove these remaining obstacles. The success of California's ADU laws provides a hopeful precedent; ADU legislation saw limited success until significant reforms in 2016. Now, ADUs constitute roughly 25% of new homes statewide. Lawmakers hope that applying similar streamlining and protections to SB 9 could catalyze a similar wave of small-scale infill housing.

Conclusion

SB 677 represents a critical refinement in California's strategy to address its housing shortage. By fine-tuning previous laws, empowering homeowners, and dismantling key regulatory hurdles, it aims to accelerate the creation of urgently needed housing.

For homeowners, it offers new avenues to maximize property potential. For cities and communities, it promises expanded housing options and faster progress towards affordability goals. For the state, it underscores a determined commitment to tackling one of California's most significant challenges. As the bill advances, its progress warrants close attention from residents, advocates, and policymakers.