AlphaX Marks Construction Start on California’s First SB 684 Starter Home Project in Campbell

On March 6, AlphaX officially broke ground on Mercury Lane Townhomes, a six-home townhouse development located at 300 Redding Road in Campbell, California. The project marks the first housing development in California to receive approval under Senate Bill 684 and advance into the construction phase, representing a major milestone in the implementation of the state’s emerging starter home.

We also want to sincerely thank Campbell leadership — former Mayor Sergio Lopez, Mayor Dan Furtado, Campbell Council member Terry Hines, Council member Anne Bybee, Community Development Director Rob Eastwood, the City’s senior planner, and the Public Works team — for your leadership, support, and commitment to helping make this vision a reality.

And to our policy partners at California YIMBY, including Nolan Gray and Muhammad T. Alameldin, thank you for the leadership in advancing housing solutions across California.

Although Mercury Lane Townhomes will deliver six homes on a relatively small infill site, the importance of the project extends far beyond its size. In a state where housing affordability and entry-level homeownership remain pressing concerns, this development serves as an early real-world test of California’s missing middle housing policy pathway. More importantly, it demonstrates that small-scale, ownership-oriented housing can move from legislative concept to physical construction when policy, execution, and local coordination align.

The event opened with remarks from housing policy researcher Nolan Gray, speaking on behalf of California YIMBY. He reflected on the legislative background of SB 684 and SB 1123, emphasizing that reducing approval uncertainty and creating a more transparent entitlement pathway are essential to restoring small- and mid-scale housing production. His remarks reinforced a key principle behind the legislation: that a more predictable approval process is fundamental to improving housing attainability.

Senator Anna Caballero noted during the ceremony that the project reflects the combined efforts of government, housing advocates, and private-sector builders working toward a shared response to California’s housing shortage. She described Mercury Lane Townhomes as an important proof point for the implementation of SB 684, demonstrating that well-structured housing legislation can support the creation of real homes for real families. Mayor Dan Furtado likewise emphasized that the project offers a meaningful example of how a city can expand housing diversity while maintaining neighborhood scale and compatibility.

Representing AlphaX at the event, Founder and CEO Stephanie Yi spoke to the broader significance of the milestone: “This moment is important because it validates a replicable path for producing starter homes in California at community scale. SB 684 brings greater clarity and predictability to the approval process, allowing responsible developers to deliver ownership housing more efficiently. Our goal is to help move missing middle housing from legislation into construction, and ultimately toward broader replication across the state.”

Under the witness of public officials, policy partners, project participants, and members of the media, ceremony attendees participated in a formal groundbreaking, marking the project’s official transition into construction.

Why the First SB 684 / SB 1123 Implementation Matters

California continues to face sustained housing supply pressure. To address the imbalance between housing demand and available inventory, the state has set a target of adding approximately 2.5 million homes by 2030. Within that effort, missing middle housing—including townhomes, duplexes, and other small-scale community-oriented residential formats—has increasingly been recognized as an important part of the solution.

Historically, smaller infill projects often faced entitlement processes similar to those required for much larger developments, making them time-consuming, costly, and difficult to advance. SB 684 and SB 1123 were designed to help address that challenge by creating a clearer and more efficient approval pathway for qualifying urban infill projects of up to ten homes. Through ministerial approval, the legislation helps reduce procedural uncertainty and creates a more stable development environment for this category of housing.

Mercury Lane Townhomes is significant because it is among the earliest demonstrations that this policy framework can function in practice. What is being tested here is not only a six-home project, but a housing delivery model that may help open a more scalable pathway for starter homes and ownership-oriented infill housing across California.

AlphaX’s Vertically Integrated Execution Model

As developer of the project, AlphaX led the full process from land strategy and entitlement coordination through construction commencement. Supported by a vertically integrated operating platform, the company manages the development process across land acquisition, government approvals, construction execution, and capital coordination. AlphaX currently oversees more than $510 million in assets under management and more than 1,000 residential units in operation across the San Francisco Bay Area.

In the policy-to-execution space, AlphaX has consistently focused on translating emerging housing legislation into real projects. From AB 1033 ADU condominium implementation to SB 684 and SB 1123 starter home development, the company has built a track record of moving first where new policy frameworks create opportunities for more diverse and attainable housing supply.

This milestone follows another precedent-setting achievement by the AlphaX team: the successful execution of California’s first AB 1033-based ADU separate title project, which established an early practical model for independent ADU ownership and sale. Together, these efforts reflect AlphaX’s broader capability to interpret policy shifts, structure viable development pathways, and deliver replicable housing outcomes in complex and highly regulated markets.

From Policy Possibility to Real Housing Product

Mercury Lane Townhomes is located in Campbell, California, in the southern Silicon Valley area near San Jose. The site benefits from established surrounding infrastructure and commuter accessibility. The project is planned as a six-unit townhouse community, with each home including a two-car garage and a layout intended to respond to practical household needs.

While modest in scale, the project is positioned to fill a meaningful gap in the market: ownership-oriented housing that can serve as a more attainable entry point in a high-cost region. In an area where median home prices remain elevated, the significance of Mercury Lane lies not in scale alone, but in the development logic behind it. Rather than relying on size, the project demonstrates how smaller for-sale housing can be delivered through a clearer entitlement path and a more workable ownership structure.

For years, projects of similar scale often struggled to move forward due to long approval timelines and high uncertainty. Under the new policy framework, however, smaller, independently sellable homes have a greater chance of being delivered as real products in the market. As that transition occurs—from theoretical policy possibility to tangible housing inventory—starter homes begin to take shape not merely as a legislative idea, but as a practical and repeatable development model.

Looking Ahead

For AlphaX, this groundbreaking is not a finish line, but an early step in a larger effort. The company remains committed to building bridges between policy innovation and on-the-ground housing delivery, and to advancing a more diverse, ownership-oriented housing supply across California communities.

As one of the earliest builders actively implementing this next generation of small-scale housing legislation, AlphaX will continue to explore how institutional clarity, disciplined execution, and product-market fit can work together to create more sustainable pathways to homeownership in California.