Bathroom Remodelingin San Dimas, CA
Bathroom remodeling in San Dimas needs a permit once plumbing, wiring or ducts change, and the City's 2025 bathroom handout is the checklist the plan checker works from. New cabinets and counter tops are cosmetic. About 63 percent of local homes predate 1980, so plan for old pipes and call Building & Safety first.
San Dimas began as a Santa Fe Railroad town in 1887, and orange and lemon groves and packing houses dominated until the last packing house closed in 1963. The city incorporated on August 4, 1960, as the 70th city in Los Angeles County, and the census count climbed from 15,692 in 1970 to 24,014 in 1980 and 32,397 in 1990 as subdivisions replaced the groves. Census Bureau estimates (ACS 2024 five-year, read through the Census Reporter mirror) say 32.2 percent of the city's 12,370 homes went up in the 1970s and 21.2 percent in the 1980s. Many San Dimas bathrooms are four or five decades old.
This page follows the order a job takes: what the City's 2025 handout asks for in the shower and toilet area, then the electrical, fan and glass rules, the permit line, what old houses hide, shared walls and rentals, the Town Core question, and the hours of the work. The official Municipal Code site (eCode360) refused our tools, so most of what follows comes from the City's own handouts, and any code rule that rests on a third-party mirror says so. Confirm those with the City. Price tiers and phases are on our bathroom remodeling page.
San Dimas Building & Safety rules that apply to bathroom work
Where bathroom remodeling permits come from in San Dimas: City of San Dimas Community Development Department, Building and Safety Division.
- San Dimas's bathroom remodel handout requires a floor plan of existing and proposed layouts, a fire-rated assembly detail if the bathroom shares a wall with another dwelling, and a dedicated 20-amp circuit for bathroom receptacles with receptacles within 3 feet of each basin and GFCI protection within 6 feet of sinks, tubs and showers.
- Per the bathroom handout, showers need a 2 inch trap and drain (a 1-1/2 inch trap is allowed for a tub-to-shower retrofit up to 36 by 60 inches), at least 1,024 square inches of floor space with a 30 inch turning circle, a door that leaves a 22 inch unobstructed opening, and toilets of 1.28 gallons per flush or less with 15 inch center-to-side clearance and 24 inches in front.
- The bathroom handout requires each bathroom to be mechanically ventilated, with the exhaust duct ending outside (not at gable or attic vents) with a backdraft damper, an ENERGY STAR fan on a humidity control unless it serves a whole-house system, fan switching separate from the lights, and safety glazing where the bottom edge of glass near a tub or shower is less than 60 inches above a standing or walking surface.
- The bathroom handout says smoke and carbon monoxide alarms are required when the construction cost exceeds $1,000, and the city's permit handout lists shower and tub enclosure replacements among work that needs a permit.
Sources for these rules
What does San Dimas require for the shower and toilet in a bathroom remodel?
The City's 2025 bathroom handout reads like the checklist the plan checker will hold you to, so design around it from the first sketch. A shower needs a 2 inch trap and drain, and a 1-1/2 inch trap is allowed for a tub-to-shower retrofit up to 36 by 60 inches. The compartment needs at least 1,024 square inches of floor with room for a 30 inch circle, and the door must leave a 22 inch clear opening.
Toilets are limited to 1.28 gallons per flush and need 15 inches from the center to any side wall or fixture and 24 inches clear in front. Those two clearances decide whether a small hall bath keeps its toilet where it stands or needs a pocket door and a slimmer vanity. Draw the room at scale before you pick a vanity width, because the handout also asks for a floor plan of the existing room and another of the proposed one.
- Does the plan show the trap size at the shower drain?
- Is the toilet clearance drawn on the floor plan, not assumed?
- Which door swing or sliding type leaves the 22 inch opening?
Which electrical, exhaust fan and glass rules apply to a San Dimas bathroom?
Bathroom receptacles need their own dedicated 20 amp circuit, with an outlet within 3 feet of each basin and GFCI protection within 6 feet of any sink, tub or shower. The handout also asks for mechanical ventilation in every bathroom, with the duct ending outdoors rather than at a gable or attic vent, a backdraft damper, an ENERGY STAR fan on a humidity control unless a whole-house system serves the room, and fan switching separate from the lights.
Glass near water has its own line: safety glazing is required where the bottom edge of the glass sits less than 60 inches above the standing surface by a tub or shower. Smoke and carbon monoxide alarms are required when the construction cost exceeds $1,000. The California Energy Commission's summary of the 2025 Energy Code, effective January 1, 2026, adds local exhaust run continuously or on demand and at least one bathroom light on an occupancy or vacancy sensor.
Steam matters in this climate because the closest NOAA station with normals, Pomona/Fairplex, about 3 miles from central San Dimas, counts 70.5 days a year at 90 F or higher. The city's own handouts are not all on one code edition, so ask the counter which one the plan set should name.
Do you need a permit for a bathroom remodel in San Dimas?
Yes, once the work reaches pipes, wires or ducts. The City's "When do I need a permit" page treats cabinets and counter tops as cosmetic work, but it puts electrical, plumbing and mechanical changes and wall openings on the permit list, and the permit handout names shower and tub enclosure replacements outright. A one-trade job can use the Single Trade Permit, while a bathroom that touches several trades normally goes on a Combination Permit.
The counter is at City Hall, 245 E. Bonita Ave., and Building & Safety answers at (909) 394-6260. The department page lists Monday through Thursday 7:30 a.m. to 5:30 p.m. and Friday 7:30 a.m. to 4:30 p.m., while an older handout says Friday 8 to 5, so confirm before driving over. The City's Homeowner's Guide gives no plan check time for a bath. Its Planning FAQ says small projects take about 15 working days, which is a reasonable planning number until the counter says otherwise.
A contractor pulling the permit shows ID, a current state license, a City business license and proof of workers' compensation, and signs a Licensed Contractor Declaration. A homeowner acting as owner-builder signs a different declaration. Since January 1, 2025, California lets an unlicensed person take jobs of $1,000 or less, but CSLB bulletin 24-07 withholds that exemption when a permit is needed, so a permitted bathroom job needs a licensed contractor at any price.
What is behind the tile in a San Dimas bathroom built in the 1970s or 1980s?
Nobody knows until the wall is open, so a quote on a 1970s or 1980s bath should carry an allowance for what turns up. The same census estimates put 63.3 percent of San Dimas homes, 7,826 of 12,370, before 1980, and the median owner-occupied home is worth $801,800. We found no San Dimas source on which supply and drain materials went into those tract houses, so ask whoever opens the wall to photograph the pipes and the framing under the tub before anything is closed.
Lead is the other question. Federal EPA rules cover paid work that disturbs paint in housing built before 1978, and the census age bins cannot isolate that year, so the 63.3 percent is a hint, not a count. EPA's own pages refused our tools, so we are not quoting its thresholds. Ask the firm whether it is certified for lead-safe work and how demolition dust is contained.
Water is the third. Ask for a flood test on the shower pan: the drain is plugged, the pan is filled, the water line is marked, and the date and result are recorded before tile goes on. A hairline crack in dry floor tile is a cosmetic matter, while a leak behind a shower wall rots framing quietly for years.
Remodeling a bathroom in a San Dimas condo, townhome or rental
About 10.0 percent of San Dimas homes are attached single-family units, 4.2 percent sit in buildings of two to four units and 15.5 percent in buildings of five or more. The City's bathroom handout asks for a fire-rated assembly detail whenever the bathroom shares a wall with another dwelling, so a townhome bath cannot simply swap tile on a party wall without the plan showing how the rating survives. An association may add its own rules for water shut-offs, work days and elevators, and those come from the governing documents, not the City.
Renters occupy 27.6 percent of the city's 12,071 occupied homes, 3,327 of them. A tenant does not normally pull the permit, so the owner's signature belongs on the application, and a one-bath unit needs a written plan for the days the room is out of service. We did not research San Dimas rental registration or tenant notice rules, so ask the City whether your building has any. Mobile homes, 8.6 percent of the stock at 1,070 units, fall under state rules we did not read for this page.
Bathroom renovation near historic downtown San Dimas: what we could not read
The City's Town Core page says the neighborhood around the historic downtown has Town Core Design Guidelines adopted by Council in 1993, after a 1991 survey that found over 320 significant structures and two potential historic districts. Separate Bonita Avenue and residential guidelines exist too. Those PDFs are scanned images with no text we could extract, so we cannot say what they require, and we will not guess.
The LA Conservancy notes that San Dimas has no historic preservation ordinance and relies on this survey-and-design-review approach, plus the Mills Act property tax program. An interior bathroom job normally leaves the street view alone. The questions to ask Planning at (909) 394-6250 are about the parts that show: a new bath window on a street-facing wall, a relocated vent cap, or a new plumbing stack that exits through the roof. Ask before ordering fixtures, because a Planning answer can change the layout.
Work hours, inspections and paperwork for a San Dimas bathroom job
Permitted work in San Dimas runs Monday through Friday from 7 a.m. to dusk and Saturday from 8 a.m. to dusk, with no work on Sundays or holidays, and the job card must be posted near the work. The Homeowner's Guide also says construction must begin and receive an inspection within 180 days of the permit being issued, then keep an approved inspection on the books at least every 180 days. A bathroom that sits half-finished waiting on glass or tile can lapse if nobody schedules the next inspection.
MDG Builders, CSLB #1040337, is a general contractor: our office draws the plan, pulls the permit and runs the calendar, and licensed plumbers, tile setters and electricians do the field work. Ask each firm for its license number and certificate of insurance. The post on how general contractors use subcontractors lays out who answers for what.
Bathroom photos from San Dimas and nearby homes
Bathroom scenes tied to San Dimas and the foothill communities around it, from opened walls and shower niches to finished vanities. Tap a photo to enlarge it.
What bathroom remodeling costs around San Dimas
Our bathroom remodeling page prices a bath of about 35 square feet at roughly $9,000 to $18,000 for a refresh, $25,000 to $40,000 for a midrange remodel in the same layout, $50,000 to $85,000 and up for a primary bath, and $60,000 to $120,000 to add one. Four independent reads sit behind those tiers: Thumbtack's Los Angeles page, updated July 2026, with $8,495 to $26,582; Sweeten's Los Angeles guide, which starts a full bath with no layout change at $25,000, $35,000 or $50,000; the 2026 Houzz bathroom study, a national figure with a $25,000 median for a major remodel; and Remodeling magazine's 2025 Cost vs. Value report for Los Angeles, which prices a midrange bath at $27,143 and an upscale one at $85,055. None is a San Dimas quote, and we read no City fee table, so permit and plan check fees are separate lines in a written proposal. The bathroom cost guide explains what moves a bath within a tier, and the license check guide shows how to verify any contractor. Neighboring cities follow their own rules, so compare bathroom remodeling in Covina, Glendora, Pomona, Claremont and Los Angeles. A bath that adds floor area belongs on our San Dimas room addition page, a bath inside a separate unit on the San Dimas ADU page, a bath window on the San Dimas window page, and the San Dimas area page lists every trade we cover in the city.
| What it covers | Typical range |
|---|---|
| Refresh in the same layout: new vanity, toilet, fixtures, lighting, paint, limited tile | $9,000 to $18,000 |
| Mid-range full remodel in the same layout: new shower or tub, tile, vanity, fixtures, lighting and fan | $25,000 to $40,000 |
| Upscale or primary bath: stone, custom glass, freestanding tub, double vanity, heated floor | $50,000 to $85,000 and up |
| Adding a new bathroom | $60,000 to $120,000 |
San Dimas bathroom remodel questions, answered
Do I need a permit for a bathroom remodel in San Dimas?
Yes when plumbing, electrical or mechanical work changes or a wall opens, and no for cabinets and counter tops alone. The City's permit page lists shower and tub enclosure replacements and wiring and pipe changes as permit work. Ask Building & Safety at (909) 394-6260 to read your exact scope back to you before you order anything.
Do I need a permit to remodel a shower in San Dimas?
Usually, because the City's permit handout lists shower and tub enclosure replacements among work that needs one. A shower job reaches the valve, the trap and the wall behind the tile. Re-caulking or re-grouting over untouched fixtures is a different matter, so describe the scope to the counter first.
How big does a shower have to be in San Dimas?
At least 1,024 square inches of floor, with room to fit a 30 inch circle, according to the City's 2025 bathroom handout. The door must leave a 22 inch clear opening, and the drain needs a 2 inch trap, or 1-1/2 inch for a tub-to-shower retrofit up to 36 by 60 inches. Put these numbers on the plan.
How much does a bathroom remodel cost in California?
Think of a bath around 35 square feet: a refresh lands near $9,000 to $18,000, a midrange remodel with the same layout near $25,000 to $40,000, and a primary bath from $50,000 to $85,000 upward. Los Angeles data sets those tiers because no San Dimas survey exists. A written proposal sets the real number.
Can a handyman do a bathroom remodel?
Only a very small one. California lets an unlicensed person take jobs of $1,000 or less, but not when a permit is required or a worker is hired, and San Dimas wants a licensed contractor with a City business license on any permit. Verify a license on the CSLB website before you pay a deposit.
What is the difference between a bathroom remodel and a bathroom renovation?
A renovation freshens finishes and fixtures in the same layout, and a remodel changes the layout or the systems behind the walls. The difference decides the paperwork, since new tile and a vanity are cosmetic while a relocated drain or a new circuit is permit work. Use whichever word you like, but tell the City what is physically moving.
How long does a bathroom remodeling take?
Expect about 2 to 6 weeks of design and selections, then 3 to 7 days of demolition and rough plumbing, 3 to 5 days of waterproofing and cure time, 1 to 2 weeks of tile and fixtures, and 1 to 2 more for glass and the final. Permit review comes first. Back-ordered glass and tile cause most delays.
Where do you shower during a bathroom remodel?
In another bathroom if the house has one, and otherwise somewhere else, because the room is out of service from demolition to final inspection. Work can only run until dusk, so evenings are not catch-up time. A gym membership or a relative's house beats improvising in week two.
Is remodeling a bathroom worth it?
A midrange bath returns most of its cost at resale and an upscale one returns far less. Remodeling magazine's 2025 Los Angeles report shows about 89.6 percent recouped for midrange work and 42.3 percent for upscale. San Dimas's median owner-occupied value is $801,800, and no local resale study turned up, so treat the percentages as regional guides.
Tell us about your San Dimas bathroom
Tell us which side of San Dimas you live on, roughly what decade the house went up, whether it shares a wall, and which fixtures you want to move, and we will start the first visit from the City's handout.