Do I need a permit for HVAC work in
San Dimas, California?

San Dimas HVAC permits — the key details

San Dimas adopted the 2022 California Building Code, which incorporates Title 24–2022 energy standards. Every HVAC permit application must include a Title 24 Energy Compliance Report (Form NRCC-NA, available from the California Energy Commission) completed by a Title 24 certifier or the contractor; the report documents the system's cooling/heating efficiency (SEER2, HSPF2), refrigerant charge, ductwork sealing, and supply-air-temperature rise. San Dimas Building Department staff review the Title 24 report for completeness before issuing the permit — if the contractor forgets the form, the permit is marked incomplete and sits in a queue for 7–10 days while the contractor corrects it. Mechanical inspections occur at three phases: rough-in (before wall closure, if ducts are new), system start-up (refrigerant charge and airflow verification), and final (system performance and thermostat programming). If your project includes modifying electrical service (e.g., upgrading to 240V for a heat pump), a separate electrical permit is required; electrical work must be completed by a California-licensed electrician, and the electrical inspector must sign off before the mechanical final can be approved.

San Dimas distinguishes between replacements and upgrades. A like-for-like replacement (same cooling tonnage, same fuel type, same location) may qualify for expedited over-the-counter review — typically 5–7 business days if the Title 24 report is pre-drafted. However, if you're upsizing capacity (e.g., from a 2-ton AC to a 3-ton unit), changing system type (e.g., adding a heat pump), or relocating outdoor unit, the project is classified as an 'upgrade' and enters full plan review, which takes 2–3 weeks. During full plan review, the city examines ductwork sizing, clearances around the outdoor unit (minimum 12 inches on three sides per Title 24), refrigerant line insulation (R-6 minimum per California Title 24), and compliance with local setback requirements. San Dimas does not have a city-specific overlay that exempts HVAC work — unlike some hillside or historic districts in nearby Arcadia or Sierra Madre, San Dimas treats all residential HVAC the same way. Permit fees are tiered: replacements typically cost $250–$400 (calculated as 0.75–1.0% of the system replacement cost); upgrades or new installations cost $400–$800 depending on tonnage.

Exemptions are narrow. Per California Building Code Section 308.4, you do NOT need a permit for repair work that does not alter the system's capacity, efficiency, or location — for example, replacing a failed compressor, rewiring a thermostat, or patching ductwork with mastic. However, San Dimas Building Department interprets 'repair' strictly: if a compressor replacement involves adding new refrigerant lines or relocating the condenser, it's reclassified as a replacement and requires a permit. Similarly, adding a new thermostat without moving existing sensors is considered maintenance; replacing an old analog thermostat with a smart thermostat (which may require a remote sensor or new wiring) often triggers a permit requirement if the wiring work involves opening walls or adding new circuits. The safest assumption is to contact San Dimas Building Department (phone TBD — see contact card) and describe your exact work scope; they will confirm whether it qualifies as maintenance (no permit) or replacement/upgrade (permit required). Many contractors err on the side of pulling a permit to avoid the risk of a stop-work order later.

San Dimas's climate context affects HVAC design. The city straddles two zones: coastal areas (3B–3C, mild winters, cool summers) and foothill neighborhoods (5B–6B, freezing winters, hot summers). Coastal homes rarely need heating beyond a furnace or strip heater, while foothill homes often benefit from heat pumps or dual-fuel systems. Title 24 energy compliance is more stringent for heating-dominated climates (zone 5B–6B), requiring higher HSPF2 ratings and better ductwork sealing; San Dimas Building Department's plan reviewers are accustomed to this split and will flag undersized furnaces in foothill projects. Additionally, older San Dimas homes in canyon areas may have poor ductwork or limited attic space, which can complicate retrofit installations; if your project requires cutting new ductwork openings, framing, or structural modifications, a full mechanical and framing inspection may be required, adding 1–2 weeks to the timeline.

Next steps: (1) Call San Dimas Building Department with your system scope (tonnage, fuel type, indoor/outdoor locations, any electrical upgrades). (2) If they confirm a permit is required, obtain a quote from a California-licensed HVAC contractor — the contractor should draft the Title 24 Energy Compliance Report and submit the permit application. (3) Expect 5–7 business days for over-the-counter approval (replacements) or 2–3 weeks for full plan review (upgrades). (4) Schedule the rough-in inspection (if new ducts), system start-up inspection, and final inspection. (5) Do not operate the system or make final connections until the final inspection is signed off. If you're acting as the homeowner-builder (pulling the permit yourself), you are responsible for scheduling inspections and ensuring the work meets code; many contractors charge a $150–$300 fee to coordinate with the city and attend inspections on your behalf.

Three San Dimas hvac scenarios

Title 24 Energy Compliance and San Dimas's Strict Plan Review

California Title 24–2022 mandates that all HVAC replacements and new installations meet specific seasonal energy efficiency ratio (SEER2) and heating seasonal performance factor (HSPF2) thresholds. For San Dimas (zones 3B–3C coast and 5B–6B foothills), the minimum requirements are SEER2 16 for AC units and HSPF2 8 for heat pumps in climate zone 3B, and HSPF2 9–10 in zone 5B. San Dimas Building Department's approach is notably more rigorous than some neighboring cities: staff conduct a full Title 24 audit of the Energy Compliance Report before issuing the permit, checking refrigerant type (low-GWP required), duct insulation R-values, and charge verification method. If the report is incomplete or references an older refrigerant (e.g., R-22), the permit is marked incomplete and returned to the contractor.

The Title 24 Energy Compliance Report (NRCC-NA form) is not difficult to complete, but it requires system specifications that many homeowners don't have on hand: the indoor unit model number, outdoor unit model number, refrigerant type, design heating/cooling capacity, and ductwork insulation details. Your contractor should provide this information; if they don't, request it upfront. San Dimas Building Department's online portal (see contact card) may include a Title 24 template or reference guide. Many contractors pre-draft the report before submitting the permit application, which speeds approval by 5–10 days. If you're pulling the permit yourself (owner-builder), you can hire a Title 24 consultant (typically $200–$400) to draft the report, or ask the equipment manufacturer or a local energy-efficiency firm for a template.

In coastal zones (3B–3C), Title 24 requirements are less stringent because heating loads are minimal; contractors often choose basic heat-pump models (SEER2 16, HSPF2 8) that meet the floor. In foothill zones (5B–6B), the colder winter pushes contractors toward higher HSPF2 units (9–10), which cost $500–$1,000 more upfront but deliver 15–20% lower heating bills over the system's life. San Dimas Building Department does not mandate the higher HSPF2 units — they are required only if you want to maximize efficiency — but the plan reviewers will flag undersized units or poor ductwork design that compromises efficiency. This distinction matters if you're comparing bids: a contractor quoting a SEER2 16, HSPF2 8 heat pump is meeting code but not maximizing your long-term savings in a foothills home.

San Dimas also enforces ductwork sealing per Title 24 Section 140.4: all ductwork must be sealed with mastic or tape, and duct insulation must be R-6 minimum in unconditioned spaces (attics, crawlspaces). If your existing ductwork is leaky or uninsulated, the contractor may recommend sealing/insulation work as part of the HVAC permit. This work is often bundled into the mechanical permit ($100–$300 in labor) and inspected during the rough-in or final visit. If you decline sealing and the plan reviewer flags poor ductwork condition, the city may require a sign-off from a duct-sealing specialist or an independent energy audit (rare but possible in full plan-review cases).

Owner-Builder Permits, Electrical Upgrades, and Contractor Licensing in San Dimas

California Building & Professions Code Section 7044 allows owner-builders to pull permits for work on their own residence without a general contractor license — this applies to HVAC permits in San Dimas. However, there are strict limits: (1) you cannot hire yourself as a contractor (you must act as the property owner), (2) you can pull the mechanical permit but MUST hire a California-licensed electrician for any electrical work, and (3) the building department may request proof of ownership (deed, property tax bill). If you pull the permit yourself, you are responsible for scheduling inspections, coordinating with the HVAC technician, and ensuring all work meets code. San Dimas Building Department does not charge different fees for owner-builder permits, but some inspectors are less flexible with timelines — they expect owner-builders to be on-site during inspections.

HVAC-to-electrical upgrades are common and trip up many DIYers. If you're installing a heat pump or an electric furnace, a new 240V disconnect and circuit are required. This work is NOT permit-exempt; California law requires a licensed electrician and a separate electrical permit. San Dimas Building Department will not approve a mechanical permit that includes electrical work unless a licensed electrician files the electrical permit simultaneously. The cost of the electrical permit ($200–$300) is separate from the mechanical permit, and the electrical inspector must sign off before the mechanical final. Many contractors handle both permits as a package and charge a single invoice covering both mechanical and electrical; if you're coordinating yourself, contact both San Dimas Building Department and a licensed electrician separately to ensure both permits are filed.

The licensing requirement for electrical work is non-negotiable in California and enforced in San Dimas. Unlicensed electricians or DIY electrical work on permit-required HVAC systems can result in a failed inspection, a stop-work order, and a fine of $300–$600. Insurance also becomes problematic: if a system failure causes injury or property damage and an unlicensed electrician did the work, the claim may be denied. Many homeowners assume they can handle simple wiring (e.g., running 240V), but San Dimas inspectors test all circuits and connections; shortcuts are typically caught at the final inspection.

If you are the homeowner-builder pulling the mechanical permit, expect to coordinate closely with your HVAC contractor and electrician. The mechanical permit application will ask for the contractor's name, license number, and contact info — you can list yourself as the permit holder and the contractor as the installer. San Dimas Building Department will mail inspection notices to the permit holder (you), and you are responsible for confirming that work is ready for inspection. Plan to be on-site or available by phone during the start-up and final inspections to answer questions from the inspector about system operation and safety clearances.

Common questions