What does getPermit actually do?

getPermit reads your job details and tells you what a California city expects before you file: which permits the work triggers, the documents and plans you'll need, the fees to budget for, and the common reasons applications in that jurisdiction get bounced back. It produces a clear checklist you can act on. It does not submit to the city for you — you (or your permit person) stay in control of what gets filed.

Is there a human involved, or is it just AI?

Both. The AI does the research and drafts the assessment and checklist; an experienced permit coordinator reviews and approves it before it's treated as authoritative. The human check is the point — it's how we keep it trustworthy in a process where a wrong filing has real consequences.

Which cities do you cover?

We're starting deep in California rather than shallow everywhere. For a city we haven't fully mapped yet, we'll give you accurate general California guidance and point you to that city's official building department — and you can join the waitlist to be notified when we cover it in depth. We will not invent city-specific fees or timelines we haven't verified.

Solo electricians, plumbers, and HVAC contractors, and small general contractors who don't have a dedicated permit department and lose billable hours to permit admin.

How much does it cost?

It's pre-launch. Join the waitlist and you'll get founder pricing, your jurisdiction prioritized, and a direct line to the team. No spam, no credit card.

We're onboarding a first set of California contractors. Join the waitlist with your city and trade so we can prioritize the jurisdictions our early users actually work in.

Duct replacement permits in Sunnyvale, CA

General California guidance last updated September 23, 2026 · Sunnyvale data fully re-verified August 10, 2026

What HVAC contractors need to know about pulling a duct replacement permit in Sunnyvale (Santa Clara County).

Short answer

In California, replacing or extending ductwork requires a mechanical permit, and the Energy Code (Title 24, Part 6) treats it as an alteration: replacing a duct system entirely — or adding/replacing more than about 40 linear feet in unconditioned space — generally triggers duct sealing with third-party HERS leakage testing. Ducts must meet the insulation R-value for the climate zone. A C-20 (HVAC) licensed contractor generally pulls it.

Sunnyvale accepts submittal through the E-OneStop Online Services (Tyler EnerGov) and has adopted the 2025 California Building Standards Code (with Sunnyvale amendments). Fee details and sources are below.

Sunnyvale permit data

Sourced from public City of Sunnyvale documents — every field carries the source URL and verification date.

Permit portal

E-OneStop Online Services (Tyler EnerGov)

verified Aug 10, 2026 · source · All services are online through E-OneStop — apply for permits, search permit and plan history, upload documents, receive and respond to city comments, schedule inspections, and make payments

Adopted code edition

2025 California Building Standards Code (with Sunnyvale amendments)

verified Aug 10, 2026 · source · The city lists the 2025 California Building, Residential, Electrical, and companion codes as current; adopted by Ordinance 3248-25 on October 21, 2025 (Sunnyvale Municipal Code Ch. 16.16: https://ecode360.com/42720766), with local amendments effective January 1, 2026 per the council ordinance record (https://sunnyvaleca.legistar.com/LegislationDetail.aspx?ID=7682689&GUID=33162351-432E-4616-996F-0D05C49AF7D2)

Fee schedule

FY 2026-27 Building Permit Fees — effective August 18, 2026

verified Sep 13, 2026 · source · Linked as "FY 2026/27 Building Permit Fees" on the Applications, Fees and Forms page

City of Sunnyvale One-Stop Permit Center →All verified Sunnyvale data →

The general picture in California

Ductwork replacement is permitted mechanical work across California, and the review is mostly an Energy Code review. Title 24, Part 6 treats duct work as an alteration: replace the system, or add or replace more than about 40 linear feet in unconditioned space, and duct sealing with third-party HERS leakage verification generally follows — documented on a CF1R-ALT and registered before final. The materials layer is simple but strictly checked: insulation at the climate zone's required R-value (R-6 or R-8 in most cases), joints sealed with mastic or listed UL 181 tape — never cloth-backed duct tape — and flex duct supported so it isn't kinked or compressed. Because the HERS rater is independent, the schedule needs their test and registration between substantial completion and final inspection. Fees, forms, and inspection scheduling are set per city — confirm with the local building department.

For deeper background that isn't Sunnyvale-specific, see the statewide duct replacement guide.

Typically needs a permit

Duct replacement itself triggers a permit in nearly every California jurisdiction, Sunnyvale included. Sunnyvale-specific variations are confirmed with the issuing department above.

Usually doesn't (general norm)

Maintenance sealing of accessible duct joints (verify locally)
Replacing registers and grilles
Repairing insulation on existing ducts

Documents & plans generally required

Mechanical permit application
Contractor license and city business registration
Duct layout with sizes, materials, and the equipment served
Insulation R-value spec meeting the climate zone (commonly R-6 or R-8)
Energy-compliance form (CF1R-ALT) and HERS registration where testing is triggered
Support/hanger spacing and connection method for flex duct

Common reasons duct replacement applications get bounced

Code-rooted patterns across California — not a Sunnyvale-specific rejection rate.

Missing CF1R-ALT or HERS registration when the scope triggers duct testing
Insulation R-value below the climate-zone requirement
Cloth-backed duct tape as the sealing method — sealing must be mastic or listed (UL 181) tape
Leakage over the allowed percentage at the HERS test
Flex duct unsupported, kinked, or compressed to the point of choking airflow
Scope written as a 'repair' when most of the system is being replaced

The inspection sequence

A typical order — the number of stops and exact sequence vary by jurisdiction and scope.

1Rough inspection where ducts are concealed in framing before cover
2Final inspection with the system complete and the HERS duct-leakage results registered where required

Licensing — who can pull it

Duct replacement in California is generally C-20 (HVAC) licensed work; a B (General Building) contractor may pull within a larger remodel under CSLB rules. The HERS duct test is performed by an independent third-party rater, not the installing contractor.

Other verified Sunnyvale notes

One-Stop Permit Center: City Hall, 456 W. Olive Ave., 2nd floor; 408-730-7444; Planning, Engineering, and Building counters open weekdays 8 AM–noon and 1–5 PM (closed weekends and City holidays).
verified Aug 10, 2026 · source
Over-the-counter (OTC) building plan-check appointments run in the mornings — generate the building permit online first with the project description "OTC", submit plans, then request the in-person slot.
verified Aug 10, 2026 · source
Building inspections are scheduled through the online service or by phone at 408-730-7790; the general contractor is responsible for scheduling and being present for all inspections.
verified Aug 10, 2026 · source

Frequently asked questions

Does a duct repair need a permit?

Small like-for-like repairs are often treated as maintenance, but replacement and extension are permitted mechanical work — and once the altered footage in unconditioned space passes roughly 40 linear feet, the Energy Code's sealing-and-testing requirements generally come with it. Describe the real scope; cities notice 'repairs' that replace half a system.

What leakage does the HERS test allow?

The allowed leakage is a percentage of system airflow set by the Energy Code, and it differs for new, entirely replaced, and altered duct systems. The practical version: mastic at every joint, tested by an independent HERS rater, results registered — an unregistered test doesn't close the permit.

What R-value do ducts need?

Title 24 sets duct insulation by climate zone — commonly R-6 or R-8 for ducts in unconditioned space, with R-8 required in many zones. The CF1R-ALT documents the value for the project's zone, and both the inspector and the HERS rater look at the duct label.

Do I need a separate permit if I'm also replacing the furnace or AC?

Usually one mechanical permit covers both scopes, but the energy paperwork compounds — the equipment changeout triggers its own measures and the duct replacement its own. The trap is pulling an equipment-only permit and 'discovering' the duct replacement at final.

Other jobs in Sunnyvale

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