Before You Build in Milpitas, CA: Permit & Rule Checklist (2026)

On the valley floor, Milpitas Zoning Ordinance Section C.2.040 caps fences and walls at 42 inches within a required front setback, 42 inches within 10 feet of a street side property line (six feet beyond 10 feet), and six feet within interior side and rear setbacks. Corner-lot visibility-triangle fences may not exceed three feet.

Milpitas Building and Safety follows the California Building and Residential Codes: fences not over seven feet high are exempt from a building permit. Fences taller than seven feet, and retaining walls over four feet measured from the bottom of the footing, do require a permit. A separate zoning review still applies to height and placement under Section C.2.040.

Milpitas has no special shared-fence cost ordinance, so California's Good Neighbor Fence Law, Civil Code Section 841, controls: adjoining owners are presumed to share equally in the cost of a boundary fence, and a 30-day written notice is required before incurring costs. Locally, raising a rear or side fence to eight feet requires written consent of adjoining owners.

In Milpitas, a retaining wall not over four feet measured from the bottom of the footing to the top of the wall is exempt from a building permit, unless it supports a surcharge or impounds liquids; taller or loaded walls require a permit. Combined wall-plus-fence height counts toward the zoning fence limits in Section C.2.040.

Milpitas Zoning Ordinance Section C.2.040 favors finished, neighborhood-appropriate materials. Concrete block must be stucco-finished or decorative split-faced and capped (plain block barred), while barbed wire near sidewalks, electric fences, and most chain link are prohibited. Hillside-district fences must use wood posts and framework and be openwork.

Milpitas requires a building permit to construct, remodel, or alter any swimming pool, spa, or hot tub, per the city's Office of Building Safety residential pool handout. A pool is any structure holding water over 24 inches deep. Above-ground pools and spas may only require plumbing and/or electrical permits plus a barrier inspection.

Milpitas implements California's Swimming Pool Safety Act through its Pool/Spa Safety Requirements Certificate. A qualifying pool enclosure must be at least 60 inches high with self-closing, self-latching gates that open away from the pool and have a latch placed no lower than 60 inches above the ground.

Milpitas requires every new or remodeled residential pool or spa to install at least two of seven drowning-prevention safety features under its Pool/Spa Safety Requirements Certificate (CBC 3109 / Swimming Pool Safety Act). Options include enclosures, mesh fencing, ASTM safety covers, door and pool alarms, and self-latching door devices.

In Milpitas, above-ground pools and spas may only require plumbing and/or electrical permits plus inspection of the barrier, per the Office of Building Safety. Manufacturer installation specifications must be submitted, and the same drowning-prevention barrier requirements apply as for in-ground pools.

Milpitas treats hot tubs and spas as pools when they hold water over 24 inches deep, requiring permits and drowning-prevention safety features. Hot tubs and spas may use a locking safety cover meeting ASTM F1346 instead of the other safety devices. Portable outdoor spas still must meet in-ground pool setbacks.

Milpitas regulates ADUs under Municipal Code Section XI-10-13.08 (Accessory Dwelling Units), implementing California's ADU law. One ADU plus one Junior ADU are permitted ministerially on a single-family lot not subdivided under SB9. The streamlined detached ADU may be up to 800 sq. ft. with four-foot side/rear setbacks and a 16-foot height limit; a JADU is capped at 500 sq. ft.

Converting a garage in Milpitas requires a building permit and a Garage Conversion plan submittal; the City advises contacting Planning and Engineering first to confirm feasibility. Converting a garage to an ADU or JADU is allowed under Section XI-10-13.08 and the Safe ADU Legalization Program, but the conversion must meet specific California Building/Residential Code separation, vapor-retarder, and heating requirements.

Sheds and other detached accessory buildings are governed by Milpitas Municipal Code Section XI-10-54.08 (Accessory Buildings and Structures). In residential (R) districts a detached accessory building must sit on the rear half of the lot, at least six feet from any dwelling on the same lot, and no closer than three feet to a rear lot line. Cumulative rear-yard accessory coverage is capped at 30% of the required rear yard.

Milpitas treats carports as covered off-street parking. A carport is a 'type of parking allowed' under Off-Street Parking Regulations (Municipal Code Section XI-10-53), and as a roofed structure it is also subject to the accessory-building placement rules in Section XI-10-54.08. Residential parking layouts must provide at least 25 feet of unobstructed backing/maneuvering distance measured from the garage or carport opening.

Milpitas has no separate tiny-home ordinance. A tiny house on a permanent foundation is regulated as a dwelling/ADU under Municipal Code Section XI-10-13.08 and must meet the same building code as any home. A movable tiny house on wheels is a vehicle under California law (it must be registered and plated) and is not a permitted permanent dwelling on a residential lot; some California cities allow movable tiny houses as ADUs, but Milpitas's code does not establish that pathway.

Backyard fire pits and portable outdoor fireplaces are governed by the California Fire Code adopted by Milpitas (Section 307). Recreational fires must keep required clearances from structures and combustibles, be attended, and have extinguishing equipment ready. Use is banned on Spare the Air alert days.

Open outdoor burning of yard waste, trash, and other materials is effectively banned in the Milpitas area. The Bay Area Air Quality Management District (BAAQMD) prohibits open burning except for narrowly defined permitted categories, and any allowed burn requires advance notification and a designated burn day.

Removing a heritage, protected, or street tree in Milpitas requires a City permit. A protected-tree permit is triggered at 56 inches of trunk circumference on residential lots and 37 inches on commercial, industrial, vacant, and subdivision properties, per Ordinance 201.5, Section 7.

In Milpitas, residents may trim branches under 2 inches in diameter on their own trees without a permit, but pruning heritage, protected, or street trees requires written City permission. Street trees in the public right-of-way are maintained by the City and may not be pruned by residents.

Under the Milpitas Water Conservation Ordinance (Title VIII, Chapter 6), outdoor irrigation is limited to four designated days per week, only before 9 a.m. and after 6 p.m. Watering within 48 hours of rain, runoff onto pavement, and potable irrigation of non-functional turf are prohibited.