SB15 planning law

SB15 planning law improves property developers’ profitability.

The passing of SB15 planning law is a watershed moment in town planning for the urban housing landscape.  The change in law significantly improves profitability for developers in inner city urban areas. The Senate signed SB15 planning law for commencing 1 September 2025, marking a pivotal shift in zoning regulations for developments.  The bill was passed during the 89th Legislative Session and became effective on 1 September, 2025.  The Act will address the growing shortage of affordable housing in cities by easing restrictions on lot sizing and density.

SB15 planning law increases residential urban design density.

The Act opens a new chapter of opportunities to innovate in compact, efficient, and affordable home designs.  SB15 planning law primarily targets municipalities with populations exceeding 150,000 that are located in counties greater than 300,000 residents.  It applies specifically to unplatted tracts of land five acres or larger zoned for single-family homes.  The Act does not include sites near airports, military bases or law enforcement facilities.

Planning changes under the Act.

SB15 planning law prohibits local governments from enforcing overly restrictive zoning rules that could hinder denser development.  The main planning changes are very generous and include the following.

• Under SB15 planning law, cities can no longer require developers to size residential lots to be larger than 3,000 sqft. They cannot also force lot widths greater than 30 feet or deeper than 75 feet.  Lowering the minimum lot size, effectively lowers the barrier for creating smaller more affordable parcels.
• Zoning cannot impose density ratios that prevent building a single-family home on any lot of at least 3,000 sqft.  Under SB15 planning law encourages more homes per acre without compromising on single-family zoning.
• For these compact lots less than 4,000 sqft or less, municipalities are barred from mandating excessive setbacks.  Boundary setbacks are limited to 15 feet front, 10 feet back, and 5 feet sides with covered parking.  Cities cannot mandate more than one parking space per unit or over 30% open/permeable space.  Additionally, buildings can reach up to three stories (each up to 10 feet high) without restrictions on bulk or wall articulation.

Exclusions under the Act.

These reforms don’t touch short-term rentals, individual lot utilities like sewers or wells, or uniform rules like stormwater mitigation that apply to all developments. Homeowners’ associations and private agreements remain free to enforce their own standards.  Exceptions exist for environmental protections, such as aquifer recharge zones or erosion controls, ensuring sustainability isn’t overlooked.

Legal enforcement against municipalities.

There’s also some compliance teeth behind SB15 planning law for enforcement against cities.  If cities don’t comply, affected individuals or housing organizations to commence legal action.  Courts have been empowered to issue injunctions against municipalities and award attorney‘s fees to winners.

Why the SB15 Act matters for architects.

For architects, SB 15 isn’t just a policy tweak—it’s a catalyst for creativity in urban residential design.  The state is grappling with housing affordability amid rapid population growth.  The SB15 Act positions architects at the forefront of solutions by enabling higher-density projects without rezoning to multi-family.  Imagine designing clusters of modern townhomes or efficient single-family residences on what were once oversized lots. Smaller footprints mean architects can experiment with vertical space, incorporating features like rooftop gardens and modular builds.  Energy-efficient layouts that maximize natural light and ventilation will be a must for this brave new world in planning.  This aligns with trends toward sustainable urbanism where compact designs reduce sprawl.  The urban infrastructure and fabric will have lower infrastructure costs and promote walkable neighborhoods.

Every architectural opportunity has it’s challenges.  Architects will need to navigate shared driveways, limited parking, and storm water requirements creatively.  In aquifer-sensitive areas, designs must prioritize water conservation, offering a chance to showcase expertise in eco-materials and systems.  The Act could spur a wave of innovative projects, from starter homes for families to downsized options for empty-nesters.  Invariably, this Act will boosting the real estate market.