ADU Regulations in La Mesa, California (2026)

Regulations at a glance

Local rules & notes

Additional Lot Coverage Bonus: The city grants an extra 5% allowable lot coverage specifically for ADUs on lots of 10,000 sq ft or less with an existing single-family residence. Complete Parking Waiver: Unlike many cities that only waive parking near transit, La Mesa's text appears to waive new parking requirements for all ADU creation unconditionally. Nonprofit Separate Conveyance: Allows ADUs to be sold separately from the primary residence if the property was built or developed by a qualified nonprofit corporation (AB 587 implementation). Historic District Restrictions: ADUs in historic districts must be located behind the primary residence and match the architectural style.

For the official ordinance and latest updates, check your city or county planning department.

Frequently asked questions about ADU regulations in La Mesa

• What is the maximum ADU size in La Mesa, California?

  In La Mesa, the maximum ADU size is typically 1200 square feet, depending on whether the unit is attached or detached. California state law allows up to 1,200 sq ft for detached ADUs and 800 sq ft for attached in many jurisdictions; La Mesa may follow state defaults or have local limits. Verify with La Mesa planning for your specific lot.

• What are the setback requirements for ADUs in La Mesa?

  In La Mesa, typical setback requirements are 4 feet from the side property line and 4 feet from the rear. These may be reduced to 4 feet under California Government Code § 65852.2 where applicable. Check with La Mesa planning for overlay zones or design standards that could affect your site.

• What is the maximum height for an ADU in La Mesa?

  In La Mesa, the maximum height for an ADU is generally 16 feet. State law often allows up to 16 feet for detached ADUs and up to 25 feet when within 4 feet of the property line in some cases. Confirm with La Mesa or county planning for your zone.

• Is ADU approval ministerial in La Mesa?

  In La Mesa, ADU approval is typically Ministerial (by-right) per Gov Code §65852.2. Ministerial (by-right) review means the city must approve qualifying applications without discretionary review, per California Gov Code § 65852.2. Your project must still meet objective standards; La Mesa planning can confirm the exact process.

• Are there parking requirements for ADUs in La Mesa?

  In La Mesa, parking for ADUs is generally false. California law often waives parking for ADUs within a half-mile of transit or in certain historic districts. Check with La Mesa planning for your address.