San Dimas Building Permits Guide for Homeowners

Last updated November 13, 2026. Reviewed by the Cash Home Buyers CA team.

San Dimas Building and Safety works out of City Hall at 245 E. Bonita Avenue, checks plans for compliance with the California codes as amended by the city, and, beginning January 1, 2026, accepts only plans designed under the 2025 California Codes. This guide walks San Dimas homeowners through what needs a permit, what plans to bring, how inspections and permit expiration work, and how permit history affects a sale.

The city updates forms and requirements, so confirm details with the division before you start work.

San Dimas permits at a glance

Department	Building and Safety Division, Community Development Department, City of San Dimas
Address	245 E. Bonita Avenue, San Dimas, CA 91773
Building Division phone	909.394.6260
City Hall main line	909.394.6200
Plans required	Three sets of plans, with detail depending on the scope of work
Codes	2025 California Codes, as amended by the city, for plans accepted from January 1, 2026
Inspection scheduling	Online portal; the homeowner or contractor may request an inspection; 909.394.6260 to cancel or reschedule
Permit expiration	Generally expires if no required inspection is passed at least every six months; work must commence within one year of issuance

What the Building and Safety Division does

The city describes the division’s goal as helping customers build safe, healthy and sustainable buildings that comply with applicable codes, through plan checks, inspections, record maintenance and disaster preparedness.

Its web pages include a plan checking page, an inspections page, forms and handouts, a page explaining when a permit is needed, and a solar permit center for residential solar, which the city says can automate permits, collect fees online and schedule inspections.

The city notes on its pages that information should be verified with the city. That is good advice for any homeowner, because code editions, forms and handouts change from year to year.

What needs a permit in San Dimas

The city’s permit page says permits are required when constructing, remodeling or enlarging a building or structure, and for other improvements to your property.

Its list includes new buildings and accessory structures, demolition of all or part of a structure including patio covers, additions including patio covers, garage conversions, and remodels that add or remove a wall, window or door or enlarge a window or door opening.

It also lists window installation, replacement or retrofit, decks and balconies, electrical work including panel upgrades, repairs, relocations and new circuits, and plumbing work.

The list goes on to water heaters, water and sewer line replacement, septic work, irrigation systems with a backflow preventer, furnace and air conditioning installation or replacement, fences and walls higher than 6 feet, retaining walls taller than 2 feet 10 inches (or any height if they support a surcharge such as a slope), roof installation or replacement, driveways and driveway approaches, swimming pools including above-ground pools, and spas. Self-contained portable plug-in spas need only an electrical permit.

Cosmetic work such as painting, wallpapering, carpeting, cabinets and interior trim does not need a permit. Minor roof repair is allowed without one if it does not exceed 5 percent of the roofing material overall, or is concentrated in a single area of 32 square feet or less cumulative over three years.

Replacing washers and faucets, repairing electrical fixtures on existing wiring, replacing switches, plugs and light ballasts, and pumping out a septic system are also listed as not needing a permit.

Step by step: a San Dimas permit

1. Confirm what you need

Call the Building Division at 909.394.6260 or the Planning Division at 909.394.6250. The city’s planning FAQ notes that a building permit is needed for a fence taller than 6 feet or a storage shed over 120 square feet, and that fencing may not exceed 42 inches in a front yard or six feet at the side and rear property lines. Zoning limits apply even when no building permit is needed.

2. Check your HOA

The plan checking page says that if your neighborhood has a homeowners’ association, you need the association’s approval stamp on your plans before you submit them to the city. Check your CC&Rs and HOA requirements first.

3. Prepare three sets of plans

The city asks for three sets. Typical plans include a plot plan showing the location of the proposed construction, a foundation plan with slab and footing details and framing attachments, a framing plan with dimensions, insulation, wall coverings and roofing, exterior elevations, a showing of compliance with minimum energy efficiency standards, and basic electrical, heating and air, and plumbing layouts.

4. Submit for plan check

Plans are checked against the latest adopted California Codes as amended by San Dimas. The page does not state a turnaround time or fee table, so ask the division when you submit and keep your correspondence.

5. Build and request inspections

Once the permit is issued, construction is inspected at stages to confirm it matches the approved plans and the California codes.

Inspections and permit expiration

Construction projects are inspected at various stages. The city’s list includes foundation forms and steel reinforcement before concrete is poured (including rough underground waste plumbing), foundation after a slab pour, rough plumbing and rough electrical, plumbing top-out, HVAC rough and duct, electrical wall and ceiling rough, framing including shear panels before insulation and drywall, insulation, drywall, roofing, and the plumbing, HVAC and electrical finals plus the building final.

To schedule, use the online portal linked on the inspections page; either the homeowner or the contractor can request an inspection. To cancel or reschedule, call 909.394.6260. The page does not state a required notice period or inspection hours, so confirm them when you pull the permit.

The city says a building permit generally expires if you do not pass a required inspection at least every six months, and that the California Building Code requires construction to commence within one year of issuance to keep the permit valid.

A permit that lapses in the middle of a job is a common surprise when a home is about to be listed, so ask the division where your permit stands before you put the house on the market.

Permits and selling a San Dimas house

Buyers and lenders ask about permit history, and California sellers generally disclose known unpermitted work on the Transfer Disclosure Statement. Our statewide guide to selling as-is with unpermitted work explains what disclosure involves, and the seller closing costs guide shows what else to budget. If tenants live in the home, read the tenant-occupied home sale guide.

When a San Dimas home has an open permit, an expired one, or work done without a permit, you generally have three options: finish and finalize the permit before listing, disclose the work and negotiate on the open market, or sell as-is to a cash buyer who takes the house in its current condition. Use this checklist:

• Ask the city’s building division for the permit record on your address.
• List every addition, garage conversion, enclosed patio or outbuilding, and note which have permits.
• Gather final inspection records, plans and contractor invoices.
• Ask what plans, fees and inspections it would take to permit each unpermitted item.
• Compare that cost and time with a no-repairs cash sale. New construction can also be reassessed for property tax, which our Prop 13 guide explains.

Questions to ask the San Dimas building division before you start

• Does my project need Planning or Engineering approval in addition to a building permit?
• Is there an exemption that applies, and what conditions come with it?
• What plan-check deposit and fees apply, and how long will review take right now?
• What inspections will be required, and in what order?
• Can an existing unpermitted structure be legalized, and what would that involve?

Common permit mistakes homeowners make

The most common problems are starting work before the permit is issued, letting a permit expire, skipping a required inspection, and assuming a contractor pulled a permit when none exists. Each one can surface years later when a buyer’s agent, appraiser or lender asks for records.

A lapsed or never-finalized permit is easier to resolve while you still own the home and can answer questions from the city. If you are not planning to stay, decide early whether finishing the permit or selling the house as it stands makes more sense.

If you hired a contractor, ask for a copy of the permit and the final inspection record and keep them with your closing documents. A finaled permit is the clearest evidence that the work was inspected. Our capital gains guide also explains how improvement costs may matter when you sell.

How to sell a house in San Dimas

1. Ask Building and Safety for the permit record on your address.
2. Collect permits, final inspection records and any city notices.
3. Request a no-obligation cash offer for the house as it stands.
4. Choose your closing date.
5. Close with no repairs, permit cleanup or showings required.

See also our San Dimas page, the San Dimas as-is sale page, the inherited house page, the San Dimas cash offer process and the Los Angeles County hub.

Frequently asked questions

Where is the San Dimas Building and Safety Division?

At City Hall, 245 E. Bonita Avenue, San Dimas, CA 91773. The Building Division phone is 909.394.6260, and the city’s main line is 909.394.6200.

Which building codes does San Dimas use?

The city checks plans against the latest adopted California Codes as amended by San Dimas, and says that starting January 1, 2026 it accepts only plans designed under the 2025 California Codes.

How many sets of plans does San Dimas require?

Three sets, with the level of detail depending on the scope of work. If your neighborhood has an HOA, the HOA’s approval stamp is needed before you submit.

How do I schedule an inspection in San Dimas?

Use the online portal linked on the city’s inspections page. The homeowner or contractor can request an inspection, and 909.394.6260 handles cancellations and rescheduling.

When does a San Dimas building permit expire?

The city says a permit generally expires if you do not pass a required inspection at least every six months, and construction must commence within one year of issuance.

Can I sell my San Dimas house with unpermitted work?

Yes. You can disclose it and sell as-is, including to a cash buyer. Our statewide guide explains the disclosure rules.

More guides

• We Buy Houses in San Dimas
• We Buy Houses in Los Angeles County
• Los Angeles County Property Tax Guide
• San Dimas Code Enforcement Guide
• San Dimas Zoning and ADU Guide
• Sell a San Dimas House As-Is
• San Dimas Cash Offer Process
• Glendora Building Permits Guide
• All California Guides

Sources

• City of San Dimas: Building and Safety
• City of San Dimas: When Do I Need a Permit
• City of San Dimas: Plan Checking
• City of San Dimas: Inspections

This guide is general information from public sources, not legal advice. Confirm current rules, fees and hours with the city.