# Electrical panel upgrade in San Francisco

> Electrical panel and service upgrades in San Francisco: panel inspection, load calculation, PG&E's process, overhead vs underground service and DBI permits.

URL: https://fogcitysfknobandtube.com/electrical-panel-upgrade/

**Service**

A fuse box or undersized panel replaced, the service resized when the load calculation calls for it, and PG&E's side coordinated.

Last Updated: October 30, 2026

**Where**

San Francisco and the East Bay: Berkeley, Oakland, Alameda and Piedmont.

**Local rules**

- An electrical permit from DBI before new wiring goes in, then a pre-cover and a final inspection.San Francisco Electrical Code 89.127
- A separate permit for each dwelling unit, except in single-family (R-3) buildings.DBI fee schedule
- Only owner-occupants of a single-family home may pull their own electrical permit.SF Department of Building Inspection
- No insulation around concealed knob and tube without a licensed electrical contractor's certification.California Electrical Code 394.12
- Up to $2,000 toward active knob and tube for income-qualified PG&E customers in an EASE Home project.BayREN

A panel upgrade can be the first electrical job an older house gets, and it is easy to mistake for the whole job. A new panel changes what protects the circuits and how much power the house can draw. It does not change the wire in the walls. Every knob and tube run that was live on the old fuse box is still live on the new breakers, which is why this page treats the panel and the branch wiring as two decisions made from one set of tests.

[Fog City SF Knob and Tube](https://fogcitysfknobandtube.com/) manages electrical panel and service upgrades in San Francisco and the East Bay: fuse boxes and worn or undersized panels replaced, services resized when the load calculation calls for it, and PG&E’s side of the work coordinated. The electrical work is carried out by licensed and insured electrical contractors holding California C-10 licenses, under a DBI electrical permit.

## What happens on the first visit

The first visit starts with a panel inspection. The panel or fuse box is opened and recorded: its condition, its listing, how many spaces are free, what size each fuse or breaker is and whether that size suits the wire it protects. Oversized fuses on original circuits are a known knob and tube problem: a fuse larger than the old conductors were meant to carry lets them overheat before anything blows. The visit also records the grounding and bonding, the meter, and whether the service arrives overhead through a mast and weatherhead or underground.

Then every branch circuit is tested and mapped, so the owner knows what the new panel would feed; on its own, that half of the visit is a [knob and tube inspection](https://fogcitysfknobandtube.com/knob-and-tube-inspection/). Permit text shows how often the two scopes travel together: in San Francisco electrical permits filed since 2016 that name knob and tube, 11.0% mention a service upgrade, main panel or meter, 11.3% mention 200 amps and 27.9% mention a subpanel. One filing reads “remove and replace fuse box/meter with new meter … terminate knob and tube.” The written scope that follows lists the panel work and the wiring work as separate lines, each with its own price.

## When a house runs short of capacity

Capacity runs short for ordinary reasons. Original services were sized for lighting and a few outlets, and permit descriptions still mention 30 A and 60 A services and fuses. A kitchen remodel, a second bathroom or a laundry added over the decades can have used up what spare capacity there was. Electrification asks for more: induction cooking, a heat pump water heater, heat pump heating and a car charger each want their own 240 V circuit.

Local rules are pushing the same way. [Piedmont’s](https://fogcitysfknobandtube.com/service-areas/piedmont/) amendments to the 2025 California Electrical Code require a 240 V, 50 A circuit within 6 feet of the kitchen cooking appliance and a 120/240 V, 30 A circuit in the laundry, including when more than half of a dwelling unit’s 120/240 V wiring is replaced. [Berkeley’s](https://fogcitysfknobandtube.com/service-areas/berkeley/) BESO menu credits an electrical service panel upgrade at sale. The symptoms owners notice, such as breakers or fuses that blow when two appliances run, are worth a test, but they do not prove the service is too small: an overloaded original circuit and a small service look the same from the kitchen.

## The load calculation decides the size

A load calculation turns the guesswork into a number. It adds up the house’s general lighting and receptacle load by floor area, the fixed appliances, the heating and cooling, and anything the owner plans to add, using the California Electrical Code’s Article 220 methods for existing dwellings, then compares the result with the service rating. Piedmont has deleted one of those optional existing-dwelling methods, 220.83(A), so a calculation there follows the remaining rules.

The result picks one of three paths. If the load fits the existing service, the panel can be replaced at the same size, or a subpanel added where the main panel has no spaces left. If it does not fit, the service is upgraded, for example from 100 A to 200 A, and PG&E becomes part of the project. A load calculation done with the rewire plan in hand sizes the panel for the circuits the house will actually have, not the ones it has today; the [whole-house rewiring](https://fogcitysfknobandtube.com/whole-house-rewiring/) page explains how the two are planned together.

## A new panel does not replace knob and tube

This is the misconception that costs owners the most. Changing a fuse box for a breaker panel removes no branch wiring at all, and it can make old circuits behave worse: modern arc-fault and ground-fault breakers often trip on knob and tube circuits with shared neutrals or leakage, which the [AFCI and GFCI guide](https://fogcitysfknobandtube.com/guide/afci-gfci-knob-and-tube/) explains. Insurers know the difference too. One San Francisco permit records that an insurance company required the owner “to replace the knob & tube wiring and replace the federal pacific main breaker,” two scopes named side by side.

So the panel quote should say which circuits the new panel will feed and which of them remain on knob and tube. Where only a few are left, a [partial replacement](https://fogcitysfknobandtube.com/partial-knob-and-tube-replacement/) can be scheduled with the panel work; where most of the house is original, the full rewire usually comes first or together. The [panel upgrade vs rewiring guide](https://fogcitysfknobandtube.com/guide/panel-upgrade-vs-rewiring/) covers the decision in depth, and the [amp rating guide](https://fogcitysfknobandtube.com/guide/knob-and-tube-amp-rating/) explains what original circuits can carry.

## PG&E’s side of a service upgrade

Any new load or service change goes through PG&E. Residential panel changes, upgrades and added load up to 320 A use PG&E’s Express Connect process, which also covers relocating an overhead service, through an application on PG&E’s Your Projects Portal. PG&E says it assigns someone to the project within five business days, that a load assessment can take up to 30 days, that any engineering advance is due within 30 days of its invoice, that the contract is executed within 90 days, and that full payment is due before construction or meter installation, with no installments.

Under its Rule 15 and Rule 16 tariffs, PG&E gives a residential allowance of $3,255 per meter or dwelling unit toward service facilities, and the applicant pays PG&E’s estimated installed cost above it, plus tax. Whether that allowance offsets the upgrade of an existing service is a question PG&E answers on each job. PG&E permits only its own outside infrastructure; DBI permits and inspects everything on the house side. After the city inspector approves the work, PG&E says it typically reconnects within one day.

## Overhead and underground services

In San Francisco permit text, overhead services far outnumber underground ones. Among the 2,023 knob and tube permits filed since 2016, 63 mention an overhead service, mast or weatherhead and 5 mention an underground service. An overhead upgrade changes the mast, weatherhead, meter base and service-entrance conductors. San Francisco’s amendments require those conductors to run in a raceway such as rigid metal, IMC or PVC conduit of at least 1-1/4 inch rather than in cable, though conductors may be re-pulled in a previously approved raceway.

Underground services are concentrated where the neighborhood was built that way. SF Planning’s draft study of the city’s residence parks, many of them [west of Twin Peaks](https://fogcitysfknobandtube.com/service-areas/west-of-twin-peaks/), notes underground utilities in Forest Hill, Sea Cliff, Presidio Terrace and West Clay Park, and in Balboa Terrace north of Darien Way. There a bigger service can mean trenching from PG&E’s facilities, and PG&E says underground upgrades with trenching can exceed $10,000. In Article 10 historic districts, a new mast, meter or conduit on a facade visible from the street is an exterior change and is checked with SF Planning per address before the work is scheduled.

## Permits, the Green Tag and East Bay differences

In San Francisco, a panel or service change needs a DBI electrical permit, filed through PermitSF. Current DBI fees include $580 for residential work of up to 40 outlets and devices including a service upgrade of up to 200 A, and $450 for service equipment of 225 A or less as its own permit. The work is inspected, and DBI issues the Certificate to Connect Current, the Green Tag, before power is restored. The [permit guide](https://fogcitysfknobandtube.com/guide/san-francisco-electrical-permit/) has the full fee table.

The East Bay adds its own steps. [Oakland](https://fogcitysfknobandtube.com/service-areas/oakland/) requires a PG&E AIC letter for every service change-out or upgrade before its inspector releases the green tag. PG&E issues that letter only after the city permit is issued, Oakland says it can take up to three days, and same-day utility release inspections are not possible. In Oakland, a fuse box or subpanel in a clothes closet can be maintained and repaired but not altered, and adding a circuit counts as an alteration; Alameda allows circuits to be added to an existing closet panel, but swapping the panel requires code compliance. [Alameda](https://fogcitysfknobandtube.com/service-areas/alameda/) is served by Alameda Municipal Power rather than PG&E, and its rules say that modifying any portion of an existing service requires a complete service upgrade to current code, with an EUSERC-listed panel and surge protection.

## Rebates and programs

Few programs pay toward panels. Alameda Municipal Power offers an electric panel upgrade rebate of up to $1,500 when the upgrade is for switching from gas to heat pump space or water heating, for the main panel only. PG&E lists PanelBoost, which supplies smart-panel hardware for single-family homes with services of 150 A or smaller as an alternative to an upgrade; check PG&E’s page for whether it is accepting customers. The federal 25C credit that once covered panels has ended; the IRS allows it only for property placed in service by December 31, 2025.

## What the panel quote should separate

A comparable quote splits the panel, the service and meter work, PG&E’s charges, the DBI permit, and any branch-circuit work into their own lines, and says which circuits stay on knob and tube. A typical San Francisco range for a 100 A to 200 A upgrade on an overhead service is $3,000 to $10,000; the [San Francisco cost guide](https://fogcitysfknobandtube.com/guide/knob-and-tube-replacement-cost-san-francisco/) puts it next to rewiring costs, and the [cost estimator](https://fogcitysfknobandtube.com/tools/knob-and-tube-cost-estimator/) gives a first number without a call. In a building of flats, the meter bank is planned with the units, which the [apartment building rewiring](https://fogcitysfknobandtube.com/apartment-building-rewiring/) page covers.

**Scope**

## What's included

- An inspection of the existing panel or fuse box: condition, fuse and breaker sizes against the wire they protect, spare spaces, grounding and bonding, the meter and the service drop or lateral
- A test of the branch circuits, recording which still run on knob and tube
- A load calculation of the house as it is, plus everything the owner plans to add
- A written recommendation: new panel, subpanel or service upgrade, and at what size
- The DBI permit, inspection and Green Tag
- Coordination of the PG&E application, disconnect and reconnect
- New panel and main breaker, with every circuit landed, tested and labeled
- A written note of every circuit still on knob and tube after the panel work, so nothing old is left unrecorded

**Choosing the scope**

## Panel replacement, service upgrade or a subpanel

| Compare | Panel replacement, same service | Service upgrade | Subpanel added |
| --- | --- | --- | --- |
| What changes | The panel or fuse box; meter and service size stay | Panel, meter base and service conductors, plus PG&E's side | A second panel fed from the main one |
| When it fits | The load fits the service, but the panel is worn, full or a fuse box | The calculated load exceeds the existing service | The main panel is out of spaces or far from the new circuits, and capacity is enough |
| PG&E involvement | A disconnect and reconnect | An application, design and work on the utility side | Usually none |
| Knob and tube removed | None | None | None |
| DBI permit | Electrical permit, fee set by device count | $450 for service equipment of 225 A or less | Electrical permit, fee set by device count |
| Typical cost | Priced after the panel inspection | $3,000 to $10,000, a typical San Francisco range for 100 A to 200 A overhead | Priced after the load calculation |

**Read next**

## Related resources

- [Decision GuideDoes a new panel remove knob and tube wiring?A panel and the branch circuits it feeds are two different parts of the system. Here is what each upgrade changes, and why the order matters.](https://fogcitysfknobandtube.com/guide/panel-upgrade-vs-rewiring/)
- [LearnWhat is the amp rating of knob and tube wiring?Why there is no number printed on the wire, what really sets a knob and tube circuit's capacity, and what changes when modern loads land on it.](https://fogcitysfknobandtube.com/guide/knob-and-tube-amp-rating/)
- [LearnCan you add GFCI or AFCI protection to knob and tube wiring?What ground-fault and arc-fault devices actually detect, why they behave differently on old circuits, and where they fit next to replacement.](https://fogcitysfknobandtube.com/guide/afci-gfci-knob-and-tube/)
- [Cost GuideHow much does knob and tube replacement cost in San Francisco?The ranges, what moves a house within them, and the parts of the price that come from public figures.](https://fogcitysfknobandtube.com/guide/knob-and-tube-replacement-cost-san-francisco/)
- [LearnHow does a San Francisco electrical permit work for rewiring?Who can file, what DBI charges, what each inspection checks, and why a Green Tag on its own does not prove the knob and tube is gone.](https://fogcitysfknobandtube.com/guide/san-francisco-electrical-permit/)

**How a job runs**

## From the first call to the Green Tag.

### First call

Tell us what started this: an insurer's letter, an inspection report, a remodel, an attic you want to insulate.

The age of the house, the number of units and any deadline shape the next step.

### Walk-through

Circuits are tested to separate live knob and tube from abandoned runs, and attic, basement and garage access is checked.

Plaster, trim and finishes are noted, and you get a written scope and price.

### The work

The permit is filed with DBI. New cable is fished along the planned routes and openings are kept small.

The pre-cover inspection happens before anything is closed.

### Patching, inspection and the Green Tag

Once the pre-cover inspection passes, the openings are patched. Plaster patching is included and shown as its own line in the quote.

After the final inspection and the Green Tag, old runs are removed or terminated and the panel directory is updated.

**On the job**

## What this work looks like

A new gray meter and main breaker enclosure with a round glass meter on the stucco side wall of a San Francisco house

Old screw-in glass plug fuses removed from a fuse box, lying in a cardboard tray on a workbench

A bare copper grounding wire running down a basement wall to a bronze clamp on a copper water pipe

White and yellow cables entering the top of a new breaker panel through individual clamps

Before

After

**Questions**

## Electrical panel upgrade: questions

### What does an electrical panel upgrade cost in San Francisco?

A typical San Francisco range for a 100 A to 200 A panel and service upgrade on an overhead service is $3,000 to $10,000. Underground service with trenching can run past $10,000. PG&E sets its own charges case by case, and replacing any knob and tube behind the panel is a separate scope with its own price.

### How soon does PG&E restore power after a service upgrade passes inspection?

PG&E says it typically reconnects within one day once the city inspector approves the work. The steps before that take longer: the application, a load assessment that can take up to 30 days, design, a signed contract and full payment before PG&E builds anything. In Oakland, PG&E must also issue an AIC letter after the city permit, which can take up to three days.

### Why does an underground service upgrade usually cost more than an overhead one?

Because a larger underground service can mean trenching, new conduit and restoring whatever sits over the route, where an overhead service changes at the mast and weatherhead. PG&E says underground upgrades with trenching can exceed $10,000. Overhead services are far more common in San Francisco knob and tube permits than underground ones.

### Do I need a load calculation before adding a heat pump or EV charger?

Yes. A load calculation adds up what the house already uses and what the new equipment will draw, and compares it with the service. It decides whether the existing panel can take a new breaker, whether a subpanel is enough, or whether the service has to grow. It is done before anything is bought, so the panel is sized once.

### Does replacing an electrical panel need a DBI permit?

Yes. San Francisco exempts only like-for-like replacement of devices, fuses or breakers where no wiring changes. A new panel or service is permitted work: current DBI fees include $450 for service equipment of 225 A or less, and the work must pass inspection and receive a Green Tag before PG&E reconnects the service.

**Related services**

## Other work on the same wiring

### Whole-house rewiring

Every old branch circuit replaced, new circuits added where the house needs them, and the panel sized for the load.

### Partial knob and tube replacement

The circuits still running on knob and tube replaced from the panel out, with a written record of exactly what remains.

### Apartment building rewiring

Knob and tube replaced unit by unit or building-wide, with a permit for each dwelling unit and power-off windows announced to residents.