Summary:

Electrical inspections help keep you and catch potential hazards. To prepare for one after doing DIY electrical work in San Mateo, make sure you have your permit on hand. Inspectors review your entire system and any work, including GFCI/AFCI protection, grounding, bonding, breaker size, installation quality, labeling, and whether it all meets CEC/NEC code. If you fail, the city will send you a correction notice and give you a deadline to fix it.

Preparing for City Inspections After DIY Electrical Work in San Mateo: What to Expect

Time to Read	~7 minutes
What You’ll Learn	Why San Mateo requires electrical inspections How to apply for the right permits (standard vs OTC) Common inspection requirements like grounding, bonding, breaker sizing, and labeling Typical reasons DIY work fails inspection What happens if you fail and how correction notices work
Next Steps	Gather and keep your permit paperwork ready for inspection Double-check your work against common requirements to avoid failing If issues are found, address them promptly within the correction deadline To avoid compliance risks, contact Caccia Home Services to handle the work for you, including permits & code requirements

Doing your own electrical work can feel rewarding and even save you money, but finishing the job is really just one part of the process. You also need to find the right permit, apply for it, pay any related fees, buy the components…and (finally) pass inspection!

Our licensed professionals work with and in this process every single day and know how to pass safety inspections pain-free. While our number one recommendation will always be that it’s better to hire an electrician, we’re happy to share what we know if it helps you stay safe.

Below, you’ll learn everything you need to know about the inspection process, including why they matter, where to find permits, what to expect, and what to do if you fail.

Why Inspections Matter in the First Place

San Mateo requires inspections for most electrical work because of the potential for disaster if it’s done wrong. It only takes a single bad connection point or misplaced wire to cause arcing, sparks, melted wires, serious injuries, or costly residential fires.

Inspections help you and the city:

• Catch hidden problems you might not otherwise notice
• Reduce the risk of serious electrical shocks and residential fires.
• Verify that the work meets or exceeds National Electric Code (NEC) standards
• Create a record of the work you can refer to after if you sell or file an insurance claim

The risks couldn’t be higher: electrical fires caused a devastating 295 deaths, 900 injuries, and $1.2 billion in property loss in 2021 alone according to the U.S. Fire Administration. Inspections are the city’s way of lowering that risk for you and everyone else living here in San Mateo.

What Permits are Required in San Mateo?

All electrical work falls under the same broad Electrical Permit here in San Mateo, but the way you go about applying for it depends on what it is you’re trying to do.

You use one of the following two options:

The Standard Building Permit Process

The standard Building Permit Process is for large, very complex jobs like adding new circuits, rewiring your home, replacing your electrical panel, or installing an EV charger. You’ll need to submit a detailed plan and have a licensed contractor sign off on it before it’s approved.

The OTC Permit Process

The Over-the-Counter (OTC) Permit Process is what you want if you’re handling simpler, lower-risk projects like replacing a light fixture or switch. There’s no need to submit a plan. You’ll need to create an account on San Mateo’s County Online Permit Center to apply for it.

Getting Help Applying

Anyone can apply for a permit. Just keep in mind that, even if you’re approved, it doesn’t necessarily mean you can legally do the work on your own or that it will meet code.

San Mateo’s building department staff are an excellent resource if you have questions about permits or aren’t sure if your DIY electrical work calls for them. You can reach them at (650) 522-7172.

Read More: Are You Eligible for These Electrical Rebates?

Common Inspection Requirements

When city inspectors come out to your property, their number one goal is to confirm that your electrical system is safe, operational, and up to code. They’re going to look at the work itself, but they’ll also check other core components and make sure you have enough capacity in the first place.

For major projects like opening walls or digging, the process usually starts with a rough-in inspection before anything gets closed up. Once that’s finished, the inspector will come out one final time.

Simpler jobs usually only require one inspection.

The table below breaks down the most common requirements and why they matter.

Area	What It Is	Requirement	Purpose
GFCI & AFCI protection	Special outlets and breakers that shut off power if something goes wrong	Must be installed in kitchens, bathrooms, laundry, living areas, garages, and outdoors	Prevents shocks and reduces fire hazards
Grounding	Copper wires that carry stray electricity back to the panel and into the earth	Every circuit/device must tie into the main panel, which connects to a ground rod or water pipe	Provides a safe escape path for electricity
Bonding	Short wires that connect metal parts like boxes, pipes, and the panel	All metal parts must be tied back into the grounding system	Prevents shocks or arcing from stray currents
Breaker & wire size	The switches in your main panel and the wires that carry a charge throughout your home.	Both breakers and wires must be large enough to handle the size of your service.	Prevents overheating
Installation quality	The physical workmanship of boxes, circuits, wires, and other components.	Components need to be securely mounted, at the right height, supported, and free of loose connections.	Lowers the risk of fires and failures.
Labeling	Stickers or writing on your panel that identify each breaker and what it controls.	Clear, accurate labels for every circuit (e.g. “Washing Machine” “Kitchen”)	Makes it easier to identify issues or turn off a specific breaker in a pinch.
Code adherence	Compliance with NEC, CEC, and local rules	The entire electrical system must meet or exceed code	General safety and legal reasons

Preparing for the Inspection: Your Checklist

Common Reasons DIY Work Fails Inspection

DIY electrical work often seems to go just fine… until the city inspector shows up and, suddenly, they’re discovering problems you never knew you had in the first place. The simple truth is that most homeowners don’t have the same level of experience as an electrician who’s been handling it for years.

That’s why it’s easy to understand why people:

• Forget that the inspector will check the whole electrical system
• Choose a wire that isn’t thick enough to handle the electricity passing through it
• Still have an old, outdated electrical panel (or worse, knob-and-tube wiring)
• Forget to connect grounding wires on both sides (or skip it completely)
• Overfill or crowd wires into an electrical box that’s too small to hold the
• Use banned or defective parts (e.g., recycled breakers) without realizing it
• Forget about filing paperwork (or lose it before the inspector arrives)

All of these will result in a fail. It’s pretty rare for this to happen, but if the inspector happens to find a clear and present danger like active arcing or smoking/melting wires, you might even need to turn the power off temporarily until it’s fixed for safety reasons.

What to Do If You Fail (And When to Call a Pro):

First, you’ll get a “Notice of Correction/Stop Work Order” from the city. It will outline everything you need to do to fix the problem, including what they found and how it’s usually addressed. They may also set a deadline so you know exactly how long you have to get it done.

From there, you have two main options.

Do it The Hard Way (DIY Again):

• Spend hours of your free time trying to understand how to get it right
• File even more paperwork for the revision, including possibly another permit
• Risk making another mistake, which means paying more fees all over again

OR

Do It The Easy Way (Call Caccia):

• The only real “work” you have to do is pick up the phone or send a message
• You get a custom quote upfront for any and all work you want or need done
• Our licensed pros handle all permits, code requirements, and communication for you
• We send someone out to walk the inspector through everything in person

Inspections can unearth a domino-effect of trouble you didn’t even know about, which could end up costing you far more than a service call in the long run. Why take the risk? Let us handle it for you and get a high-quality result without the hassle, guaranteed.

Get Safe, Inspection-Friendly Electrical With Caccia

Having an inspector examine your wiring can feel a bit like someone looking over your shoulder while you’re taking an exam: awkward, uncomfortable, and downright painful if you get an “F”. While they are necessary, the best way to get a gold star every time will always be to hire a licensed electrician.

Don’t spend hours of your precious time pouring over YouTube tutorials, service guides, and confusing code ordinances. You have better things to do! Contact Caccia Home Services instead or call us at (650) 294-8599.