Do You Need a Permit to Remodel a Bathroom? A Bay Area City-by-City Guide (2026)

"Do I need a permit for this?" is one of the most common questions we hear. The honest answer: it depends on your city and on what's changing. Swapping tile on the same walls is treated very differently from moving a shower valve, adding a heated floor circuit or building a curbless shower.

Below is what each city's own building department publishes, with links so you can check the details yourself. Rules change, so treat this as a starting point and confirm your exact scope with the city before work begins.

A quick rule of thumb

• Usually a permit: moving or adding plumbing fixtures, new or relocated electrical (including a heated floor circuit), changing walls, windows or structure, and full bathroom remodels in many cities.

• Often no permit: purely cosmetic work like painting and, in some cities, replacing floor or wall finishes without touching plumbing or electrical.

• Watch for this: when a permit is issued, several cities require you to upgrade older non-compliant fixtures elsewhere in the house.

East Bay

Walnut Creek. The city's building permit FAQ lists kitchen and bathroom remodels as work that needs a permit, along with new or relocated plumbing fixtures and new, relocated or replaced lighting. (City of Walnut Creek, Building Permit FAQs)

Rossmoor (Walnut Creek). Rossmoor has its own Alterations & Resales Department. For at least some mutuals, a bathroom or kitchen remodel needs both an Alterations Department permit and a City of Walnut Creek permit, with the mutual's approval first. Each mutual has its own rules, so check yours. (Rossmoor Alterations and Resales)

Lafayette. Lafayette's building permits are handled through the Contra Costa County Building Inspection Department after the city's zoning check. The city's exemption list includes bathroom and other interior remodels that don't add conditioned space, but kitchens are not exempt. Confirm with the county if you're moving plumbing or electrical. (City of Lafayette, Building Permits)

Orinda. City planning review comes first, then building permits are issued by the Contra Costa County Building Department. (City of Orinda Permitting Portal)

Danville. The Town of Danville has a dedicated "Like-for-Like" bathroom and kitchen remodel submittal for replacing fixtures and cabinets in kind. Moving a showerhead, sink, toilet or outlet, or any structural change, goes through the town's additions and alterations process instead. (Town of Danville, Like-for-Like Remodels)

Pleasanton. Pleasanton's handout says a building permit is required for all new, relocated or remodeled bathrooms. Two details matter for tile work: shower pans or site-built liners must rise at least 3 inches up the walls, and curbless showers require waterproofing of the entire room. (City of Pleasanton, Residential Bathroom Alteration Requirements)

Peninsula

San Mateo. The city's bathroom remodel guide calls for a building application with plans, and lists requirements like a 50 CFM exhaust fan, GFCI outlets and pressure-balance or thermostatic shower valves. It also requires replacing non-compliant fixtures elsewhere in the house. (City of San Mateo, Bathroom Remodel Guide)

San Bruno. San Bruno's FAQ says almost every construction project requires a permit, including alterations and plumbing, electrical or mechanical changes. (City of San Bruno, FAQ)

Redwood City. A permit is required for all work not exempted by the building code; painting, flooring and similar finish work are listed as exempt examples. Larger remodels can trigger the city's fire sprinkler "50% rule." If you're only replacing tile with no plumbing or electrical changes, confirm with the city. (Redwood City, Building FAQs)

South Bay

Palo Alto. Licensed contractors can get an instant Kitchen/Bath Remodel permit for single-family homes, as long as the work stays within the existing footprint with no structural, wall, window, door or panel changes. (City of Palo Alto, Kitchen/Bath Remodel Instant Permit)

Mountain View. The city says a permit is required for all bathroom remodels, including replacing a tub or shower enclosure. Its guidance lists a non-absorbent wall finish to 72 inches in showers and a typical fee of about $400–$550. (City of Mountain View, Bathroom Remodel)

Los Altos. The city's bathroom handout requires shower pans or liners at least 3 inches high, cement or glass-mat backer board, a non-absorbent finish to 6 feet and a 50 CFM fan. Non-compliant fixtures in the house must be replaced unless the home was built after January 1, 1994. (City of Los Altos, Residential Bathroom Remodel handout)

Central Valley

Manteca. Manteca's Building Safety Division requires permits before a building is constructed, repaired or altered, and applications are submitted online through the city's permit portal. (City of Manteca, Building Safety)

Why this matters for your tile project

Permit rules shape the plan: they affect how the shower is waterproofed, how high the tile goes, which valve you use, and sometimes what else in the house needs updating. They also affect the timeline, so it's best to know up front.

When you reach out, tell Mike your city and what you'd like to change. He'll walk you through what's likely involved before you commit to anything.

Call or text 916-847-2825, or request a free estimate on our website.

This guide summarizes each city's published information as of October 2026. It isn't legal advice, and requirements can change. Always confirm with your local building department.