By Serg Nikolin, Co-Owner of Product Air Heating, Cooling, and Electric
I would never buy an older home in Western Washington without having a licensed electrician look at the electrical system separately from the general home inspection. I've seen too many houses where everything looked fine from the outside, but the wiring told a completely different story. A new outlet cover, a finished basement, or a recently remodeled kitchen doesn't tell me whether the work behind the walls was done correctly.
Our team works with homeowners across King and Snohomish counties, and one thing I keep seeing is electrical work that somebody modified without fully understanding what they were doing. During one recent week, I handled roughly 10 service calls. Every home showed signs of DIY electrical work, and in every one, I found something I considered unsafe. That's a small sample from my own experience, not a statistic about every house in Washington, but it's enough to explain why I take pre-purchase electrical inspections seriously.
When you're buying a home, you have a limited amount of time to understand what you're getting. I don't want someone discovering an expensive wiring problem three months after closing when they could have identified it during the inspection period, obtained a repair estimate, and decided what to do before signing the final paperwork.
A General Home Inspection Doesn't Tell You Everything About the Wiring
I think home inspectors provide an important service, but their inspection has a defined scope. In Washington, WAC 308-408C-110 requires home inspectors to examine accessible electrical components, including the electrical service, branch wiring, representative switches, outlets, and fixtures. They also visually inspect conductors after removing readily accessible electrical panel covers.
What the rule doesn't require is equally important. A general home inspector is not required to insert testing probes into electrical panels, operate circuit breakers, remove switch and receptacle cover plates, or perform every diagnostic procedure an electrician might use. The home inspection standard also doesn't require inspection of smoke, heat, or carbon monoxide detectors. That's why I recommend a separate electrical inspection when buying an older property, especially if the panel appears original, the house has been remodeled several times, or there are signs of unprofessional electrical work.
A licensed electrician can investigate concerns beyond the standard home inspection, but the exact work should be agreed upon beforehand. Depending on the inspection scope, that may involve checking circuit conditions, testing receptacles, evaluating grounding and bonding, or examining the panel more closely.
I also tell buyers to choose their own electrician. When you're purchasing a home, you need someone whose job is to evaluate the electrical system, not help the transaction move forward. If we find something unsafe or incorrectly installed, I want it documented, even if that makes the purchase decision more complicated.
Older Homes Often Have More Than One Generation of Electrical Work
The original wiring is only part of what concerns me in an older house. A property might have been built decades ago, expanded in the 1980s, remodeled in the early 2000s, and modified again by a more recent owner. Every phase may have involved different electrical equipment, installation practices, and contractors. That doesn't mean an old home is automatically unsafe. I've seen older equipment that was maintained properly and newer work that needed correction. What matters is the condition of the system and whether previous modifications were completed correctly.
Aluminum branch-circuit wiring is one example worth investigating. The U.S. Consumer Product Safety Commission estimates that approximately 1.5 million to 2 million homes were built with aluminum wiring systems installed between 1965 and 1973. The commission recommends having suspected aluminum branch-circuit wiring inspected by an experienced electrician and recognizes properly applied COPALUM and AlumiConn repair methods for addressing associated connection hazards.
Knob-and-tube wiring, older fuse panels, certain outdated electrical panels, and ungrounded circuits may also require closer evaluation. I wouldn't tell somebody that every older component automatically requires full replacement, but I wouldn't dismiss it simply because the lights still turn on.
The inspection should establish what is installed, what condition it's in, and whether there are safety concerns or limitations the buyer needs to understand.
A Panel Can Work Today and Still Be Too Small for Tomorrow
One issue I want buyers to consider is what they plan to do with the home after moving in. An electrical panel might handle the current household demand without obvious problems, but that doesn't necessarily mean it has adequate capacity for a new heat pump, EV charger, or other major electrical load.
In our work, I estimate that upgrading a home from 100-amp to 200-amp service comes up in roughly 15% of the properties we see. We encounter that situation more often in some older homes around Seattle, Kirkland, and Mercer Island. That's an estimate based on our service experience, not a regional requirement or a reason every older home needs a panel replacement. In fact, most homes we visit don't need that particular upgrade.
We've had projects where our technician was the only contractor who told a homeowner that the existing electrical service needed to be upgraded before the planned installation. Other contractors had proposed moving forward without identifying that limitation. The homeowner appreciated knowing about the problem before committing to the project.
I would rather have that conversation before someone buys a house. If you're planning to replace a furnace with a heat pump or install an EV charger, have an electrician evaluate the available electrical capacity while you're still reviewing the property. It may not change your decision to buy, but it can change your renovation budget.
DIY Wiring Is One of the Biggest Problems I Find
I don't assume that every homeowner who has worked on their own house did something unsafe. Washington law allows property owners to perform certain electrical work themselves, subject to restrictions. But I've seen enough improperly modified wiring to know that the presence of a finished renovation doesn't prove the electrical work was done correctly.
A project we documented in Mukilteo is a good example. Electrical work performed by the homeowner and an unlicensed HVAC contractor resulted in approximately $5,000 in corrective work and created a serious fire hazard. What initially seemed like a completed installation still needed substantial attention to correct the underlying electrical problems. This is why I look closely at signs of overheating, loose connections, improper breaker installations, corrosion, missing grounding, and changes that don't appear consistent with professional electrical work. A breaker that has been improperly double-tapped, for example, may indicate that somebody added a circuit without using an approved connection method.
The consequences of electrical mistakes can go well beyond an inconvenient repair. The U.S. Fire Administration reported 23,700 residential building electrical fires and 305 deaths in 2023. Those figures aren't specific to older homes or DIY work, but they demonstrate why electrical safety deserves serious attention during a home purchase.
I don't want to frighten buyers into assuming that every questionable outlet is a fire waiting to happen. I want them to recognize that wiring deserves the same careful evaluation as the roof, foundation, and other major systems.
A Missing GFCI Can Reveal More Than One Bad Outlet
Ground-fault circuit interrupter protection is another area where I often find problems, particularly around water. We recently inspected a home built in 2004 where the laundry area lacked the GFCI protection needed for the washing-machine circuit. From the homeowner's perspective, the outlet worked, and the washing machine operated normally. The problem was that the required electrical protection wasn't there.
Sometimes that happens after a homeowner replaces a GFCI receptacle with a less expensive standard outlet without understanding why the original device was installed. Other times, the cause is different, which is why testing matters. A standard-looking receptacle may also be protected by an upstream GFCI device or breaker, so appearance alone doesn't establish whether protection is present.
During an electrical inspection, I want to know whether protection is installed where required, whether it functions properly, and whether previous modifications have compromised the system. The same principle applies to grounding and bonding. A receptacle accepting a three-prong plug doesn't automatically prove it has a proper equipment-grounding connection. Testing and examining the relevant circuitry can reveal problems that aren't visible from the room.
Some Older Wiring Comes With Specific Washington Rules
Knob-and-tube wiring is one subject that often surprises buyers because its presence can affect renovation plans, particularly insulation work. Under WAC 296-46B-394, insulation may cover knob-and-tube wiring only when specific requirements are satisfied. A licensed electrical contractor must survey the wiring and certify that it's in good condition, the insulation must meet the Class I requirement, and the circuits must have appropriate overcurrent protection. Foam insulation cannot be installed over knob-and-tube wiring. That means a buyer planning to improve attic insulation should establish whether this wiring is present before budgeting for the project. The insulation contractor and electrician may need to coordinate, and the scope of work may be different from what the buyer initially expected.
Carbon monoxide alarms also deserve attention. Under RCW 19.27.530, sellers of qualifying owner-occupied single-family homes must have carbon monoxide alarms installed before the buyer occupies the property, subject to the law's applicable requirements and exceptions.
I wouldn't assume a general home inspection has fully evaluated those devices, because Washington's home inspection standards don't require that testing. Buyers should confirm the property's applicable alarm requirements and have missing or improperly installed devices addressed. These aren't reasons to avoid older houses. They're reasons to understand the rules that may affect the property before committing to renovations or moving in.
Schedule the Electrical Inspection While You Can Still Negotiate
One of the biggest practical mistakes is waiting too long to bring in a specialist. When you're buying a house, the purchase agreement and its deadlines matter. Under RCW 64.06.030, Washington sellers generally must provide the seller disclosure statement within five business days after mutual acceptance of the written purchase agreement, unless the disclosure is waived or the parties agree to a different timeline.
Buyers generally have three business days after receiving that disclosure to accept it or rescind the agreement, subject to the statute and any applicable contractual arrangements. That disclosure timeline shouldn't be confused with the separate inspection contingency period, which depends on the purchase contract.
I recommend discussing a specialist electrical inspection with your real estate agent before making an offer, particularly if the property has an original panel, visible modifications, or plans for major electrical upgrades.
If the electrician identifies a problem, you want enough time to understand it, obtain a written repair quote, and discuss the findings with your agent. Discovering that an electrical service upgrade is necessary during the final week before closing puts you in a much more difficult position. The report should clearly describe what was inspected, what was found, and which conditions need correction or further evaluation. I don't think a verbal reassurance that everything looks fine is enough when someone is making a major financial commitment.
What Should an Electrical Inspection Cost?
We don't publish one flat price for every pre-purchase electrical inspection because the property and requested scope can vary. I recommend asking for a written quote before the visit and confirming exactly what the electrician will inspect.
A general home inspection price is not necessarily a useful comparison. You're paying for specialist evaluation of a particular system, and the value depends on the work performed and the information documented.
I would ask whether the inspection includes a detailed panel evaluation, checks of accessible wiring, outlet and GFCI testing, grounding and bonding assessment, and written findings. Not every inspection includes the same diagnostic steps, and some conditions cannot be fully evaluated without additional access or investigation.
If repairs are recommended, obtain a separate estimate for that work. The buyer should understand the difference between identifying a problem and paying to correct it.
Electrical repairs also have permitting requirements. Under RCW 19.28.261, Washington property owners may perform electrical work on property they own without an electrician's license, subject to statutory exceptions, including restrictions involving property offered for sale within 12 months after acquisition.
Most electrical work requires a permit unless a specific exemption applies. Depending on the address, the responsible inspection authority may be Washington State Labor & Industries or a local jurisdiction with its own electrical inspection program. A handyman license alone does not authorize someone to perform regulated electrical work.
I would verify those requirements before assuming that a seller's proposed repair or a contractor's estimate includes everything necessary.
Don't Ignore the Rest of the House While Checking the Electrical System
I recommend a specialist electrical inspection, but I don't think buyers should focus so narrowly on wiring that they overlook other expensive problems.
In Western Washington, moisture deserves particular attention. The roof, attic, crawl space, insulation, ventilation, and drainage all affect the condition of the building. Water intrusion can also reach electrical components, which makes signs of leaks, corrosion, and moisture damage especially relevant.
If there has been a bathroom remodel, I would want both the plumbing and electrical work evaluated where concerns exist. If the house has an older furnace, air conditioner, or water heater, have the appropriate professional assess those systems. A sewer scope can reveal damage that a general visual inspection won't detect, and foundation concerns may require a structural specialist.
I would also contact the homeowner's insurance provider before closing to ask whether the type of electrical panel or wiring could affect coverage. Finding out about an insurance requirement after you've purchased the house is an unnecessary complication.
As an HVAC and electrical contractor, our company evaluates both heating and cooling equipment and the electrical infrastructure supporting it. That connection matters when buyers are planning improvements that involve multiple systems.
Use the Electrical Report to Make a Better Buying Decision
Once you receive the inspection report, I would separate the findings into issues requiring prompt correction, improvements that can be planned alongside renovations, and larger repair-or-replacement decisions.
An identified electrical hazard should receive immediate attention before the affected system is used. An older but serviceable panel may be something to evaluate in connection with future renovations. Aluminum branch-circuit wiring or remaining knob-and-tube circuits may require a more detailed repair plan, depending on their condition, associated hazards, and the applicable requirements.
Take the report and written repair estimates to your real estate agent. Depending on the purchase agreement and the seller's willingness to negotiate, you may be able to request corrections, a credit, or another arrangement. The inspection doesn't guarantee a concession, but it gives you documented information rather than a vague concern.
I don't want buyers pushed toward a panel replacement they don't need, and I don't want them purchasing a house without understanding a real electrical limitation. If the system is safe and has enough capacity for their plans, I want them to know that too.
Our licensed electricians serve homeowners throughout King and Snohomish counties, including Bellevue, Seattle, Kirkland, Mercer Island, and surrounding communities. Whether the property needs a simple correction or a larger electrical upgrade, I believe the buyer deserves a clear explanation of the problem and the available options.
The right time to learn about the electrical system is before you own the repair bill. Once you've closed, you can still fix the problems, but you no longer have the same opportunity to consider them as part of the purchase.
For a more detailed discussion of electrical inspection procedures, Washington requirements, common safety concerns, and pre-purchase planning, read my complete guide to electrical inspections before buying an older home in Western Washington.
Expert Conversation with Serg Nikolin
The Stone Magazine (TSM): Serg, would you really recommend a separate electrical inspection for every older home, even when the general home inspection doesn't identify a problem?
Serg Nikolin (SN): Yes, I would recommend having a licensed electrician evaluate the electrical system, especially when the house has older wiring, an original panel, or several renovations behind it. A home inspector performs a visual inspection within a defined scope. That doesn't mean the electrical system has received every diagnostic check an electrician might perform. I've seen too many problems hidden behind work that looked acceptable from the outside.
TSM: You mentioned finding unsafe electrical work during roughly 10 service calls in one week. What were you seeing?
SN: I found signs of DIY electrical work in every one of those houses, and something I considered unsafe in each. I'm not saying that proves every house in Washington has dangerous wiring. That's simply what I encountered during that particular week. It reinforces why I don't assume that an electrical installation is correct just because somebody finished the room and the lights work.
TSM: Does the age of a home automatically tell you whether its electrical system is safe?
SN: No. Age tells me what kinds of equipment and previous modifications I might encounter, but it doesn't tell me the condition of every circuit. You can find an older home with properly maintained electrical equipment or a much newer house where somebody made an unsafe modification. I want to inspect what's actually installed rather than make a decision based only on the construction year.
TSM: What are the most common electrical issues you look for?
SN: I pay attention to improper DIY modifications, overheating, loose connections, corrosion, grounding problems, missing GFCI protection, incorrectly installed breakers, and older equipment that needs closer evaluation. I also want to know whether the electrical panel can support what the homeowner plans to add. Those are different questions, and the inspection should address both safety and capacity where they're within the agreed scope.
TSM: How often do homeowners actually need to upgrade from a 100-amp to a 200-amp panel?
SN: Based on our experience, I would estimate that upgrade comes up in roughly 15% of the homes we visit. We see it more often in some older properties around Seattle, Kirkland, and Mercer Island. But most homes we visit don't need that upgrade. I don't recommend replacing a panel just because it's 100 amps. We look at the actual load and what equipment the homeowner wants to install.
TSM: What could happen if someone buys a home and then decides to add an EV charger or heat pump?
SN: They might find out that the existing electrical service needs additional work before the installation can proceed. That could affect their renovation budget. It's something I would rather identify during the purchase process, because then the buyer can account for it instead of discovering the cost afterward.
TSM: You described a case in Mukilteo involving $5,000 in electrical corrections. What does that example tell buyers?
SN: It shows that completed work isn't necessarily correctly completed work. That project involved homeowner wiring and electrical work by an unlicensed HVAC contractor, and the corrections added up to about $5,000. There was a real fire hazard. That's why I don't judge an installation just by whether the equipment turns on. I want to know whether the wiring and connections were done safely.
TSM: Should buyers be concerned if they discover aluminum or knob-and-tube wiring?
SN: They should have it properly evaluated, but I wouldn't tell someone to abandon a home purchase just because an older wiring type is present. Aluminum branch-circuit wiring has specific connection concerns, and knob-and-tube wiring can affect insulation and renovation plans. The electrician needs to establish its condition, identify any hazards, and explain what corrections may be necessary.
TSM: How much should buyers budget for a pre-purchase electrical inspection?
SN: I wouldn't give a universal price without knowing the property and what needs to be inspected. We provide pricing based on the scope. I'd tell buyers to request a written quote, confirm what the inspection includes, and make sure they'll receive written findings. If repairs are needed, get those priced separately so you understand the actual financial exposure.
TSM: When should someone schedule the inspection during the purchase process?
SN: As early as their inspection period allows. Don't wait until the last week before closing. If we find something that needs repair, the buyer should have time to get a quote and talk with their real estate agent about the options. The inspection is much more useful when there is still time to act on the findings.
TSM: Can buyers use the electrical inspection report to negotiate with the seller?
SN: They can use the report and repair estimates to support a request for repairs or credits, depending on the contract and the circumstances. That doesn't mean the seller has to agree. But it's better to have a documented problem and a real price than to tell somebody you're generally worried about the wiring.
TSM: What's the biggest mistake you see people make when buying an older home?
SN: Assuming that because the house passed a general inspection, every electrical detail must be fine. A general inspection is valuable, but it has limits. I would rather have a licensed electrician look at the system, explain what it can safely support, and document any problems before the buyer takes ownership. That gives people the information they need to decide whether the house and the potential repairs make sense for them.
