Marin County, California
Home Services in Inverness, CA
Perched above Tomales Bay, Inverness sees damp coastal weather that tests every home system. Ongaro & Sons keeps Inverness warm and dry with expert HVAC, plumbing, electrical, and solar work.
The company opened its doors in 1932. Its trades today are heating and cooling, plumbing, electrical and solar. We are Diamond Certified and hold a BBB A+ Rating. Our 2,745 Google reviews average 4.8 stars. At this end of West Marin, holding all four licenses is not a convenience. It is the difference between a job that finishes and a job that waits on somebody else's calendar.
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A heating town on a wooded ridge, and both halves matter
Two facts about the setting drive nearly every technical decision here, and neither appears in advice written for the rest of Marin.
The first is that this is one of the coolest, dampest places we work. The town sits on the west shore of Tomales Bay under Inverness Ridge, on the outer-coast side of the county, where summer arrives as fog rather than heat and July afternoons stay in the upper sixties. Inland West Marin can run substantially warmer on the very same day. The equipment brief is therefore close to the inverse of the one written for Novato or San Rafael: cooling capacity is nearly irrelevant, and what the house needs is efficient heat across a long cool season plus enough air movement that damp does not settle into it.
The second is the ridge. Lots here are steep and wooded, driveways are long, and buried infrastructure runs further and across worse ground than it does anywhere flat. That shapes the plumbing, the electrical and the outage exposure at once, and it is why an assessment here takes longer than the same assessment in town.
What a wooded ridge does to your power supply
Trees, wind off the ocean, steep terrain and few lines in. That combination produces outages for entirely ordinary reasons, on top of PG&E's Public Safety Power Shutoff program, which the utility uses in severe weather to reduce the chance of its equipment starting a fire.
For most of Inverness that is not a lighting inconvenience, because most of Inverness is on a private well. The pump is an electrical appliance and the pressure tank holds minutes, so the taps go when the lights do. Any septic system with an effluent pump is in the same position, and on a property heated by a heat pump an outage takes water and warmth together.
Backup gets designed at the panel rather than bought off a shelf. The question that decides the cost is not which generator, it is which circuits. A critical loads subpanel carrying the well pump, refrigeration and a few lighting and outlet circuits is a far smaller machine than whole-house coverage, and it is dramatically cheaper to build while the panel is already open than to retrofit two years on. On a well property the pump sets the sizing, and what matters is its starting surge rather than its running draw, which is precisely the number an undersized system gets wrong.
We are a Certified Generac Generator installer and we hold the C-10, so the generator, the transfer equipment and the panel work stay with one company on one schedule. Up a long driveway that is worth more than it sounds.
Long runs, steep ground, and what fails underneath
Distance is the recurring theme in the buried work out here.
On the electrical side, a service landing near the road and a house sitting well back means a feeder length that puts voltage drop into the design rather than the footnotes. Add a pump house, a shop or a studio and each is another run. Motors on long runs work harder and fail sooner, and equipment at the far end of an undersized feeder behaves like equipment with a fault. We measure under load rather than at rest, because a reading taken on a quiet circuit says little about what happens when a pump and a compressor start seconds apart.
On the plumbing side the same geometry applies to water and waste, and slope does the rest. A lateral running down steep ground moves water fast and can leave solids behind on the way, which fails differently from the flat-run bellies we find in town. Buried lines on a wooded lot also have company: roots follow moisture escaping any joint that leaks even slightly, arrive finer than a hair, and thicken year after year inside the pipe. Clearing roots without addressing the joint they came through buys a season rather than a solution.
Wells are their own diagnostic discipline. Pressure here is manufactured on site by a pump and a pressure tank cycling between cut-in and cut-out points, with no municipal regulator in the picture. Weak or surging water therefore starts with the tank's air charge and the switch settings rather than with the fixtures, and a tank that has lost its charge makes the pump start and stop rapidly, which is the fastest way to destroy a pump motor. Water quality on a well is the owner's responsibility rather than a utility's, so testing belongs on a schedule.
Heating equipment that suits this climate
Because the season is long, cool and damp rather than hot, a correctly sized heat pump is close to an ideal match: it spends nearly all its running hours doing exactly the job the climate asks for rather than idling through a cooling season that never really arrives.
What fails is usually the duct path. A good deal of older ridge housing was framed with no duct route at all, or had ductwork added long afterwards and never sized for whatever was eventually connected to it. High-efficiency equipment on undersized or leaky ducts delivers the rating printed on the label and nothing like it in the rooms, so we measure static pressure before specifying rather than after.
Where no usable route exists, ductless is the design rather than the compromise. Small refrigerant lines reach rooms that ducts never could, ceilings stay closed, and a room with its own thermal behavior finally gets its own control. We hold Mitsubishi Diamond Contractor Elite and Trane Comfort Specialist status, and every head is sized against the room it serves.
Refrigerant is where an older system's age turns into a decision. Domestic production and import of R-22 stopped in 2020, so a leak on equipment from before about 2010 has to be fixed with reclaimed or stockpiled stock, and that arithmetic usually points at replacement rather than repair. The successor, R-410A, is itself being phased down under the AIM Act toward a 700 GWP ceiling on newly built residential equipment. None of that touches a working system you already own.
Septic systems: a slow drain is often a tank problem
Most property out here is on an onsite system, and that changes what a symptom means before anyone opens a fixture.
A septic system is a tank where solids settle and a dispersal field where liquid returns to the soil. Slow drains throughout the house can mean a blocked building drain, which is straightforward plumbing. They can equally mean the tank is full, the outlet baffle has failed, the distribution box has shifted, or the field is saturated and no longer accepting flow. Those are not plumbing jobs in the same sense and a cable does not solve them.
The tells are worth knowing: several fixtures slowing together rather than one, gurgling across the house, odor outdoors, unusually green or soggy ground over the field, and symptoms that worsen after heavy use or a wet week. On a wooded ridge lot in the middle of the rainy season, a field that has been marginal for years will often pick January to make that clear.
Maintenance keeps the plumbing side simple. EPA's baseline is inspection at least every three years with tanks typically pumped every three to five, and roughly annual inspection where the system carries pumps or float switches. EPA is also blunt that chemical drain openers do not belong in the system, which on septic is not a preference: the tank runs on living organisms and a slug of caustic passes straight through to them.
Permits at this end of the county
Inverness is unincorporated, so the authority is Marin County's Community Development Agency rather than a town building department.
The practical detail is that the county runs two routes and most ordinary house work falls into the quick one. Replace something the building already has and the county asks for no drawings whatever. The application is the submission, and the permit issues at the speed you can type. Those categories are close to a list of everything that goes wrong on a peninsula house: the water heater, gas piping, bath and kitchen fixtures, a mechanical changeout, ductwork, circuits and outlets, the service itself, a charging station.
Anything beyond a replacement takes the plan review route. Inverness also sits inside the Coastal Zone, so some projects need coastal development review through the county unless they fall within an exclusion, and that is a design-stage question. Raised late it costs weeks rather than money.
Two statewide requirements ride along regardless. Title 24 energy compliance attaches to replacements, under the 2025 Building Energy Efficiency Standards in force since January 2026. And Health and Safety Code section 19211 requires "all new and replacement water heaters, and all existing residential water heaters" up to 120 gallons to be braced, anchored or strapped against earthquake displacement. Read that phrasing carefully, because it reaches the unit already standing in your building rather than only the next one.
The air rule, stated precisely
Marin sits inside the Bay Area Air Quality Management District, so its zero-NOx appliance requirements reach this address. What they regulate is the transaction rather than the appliance: an installer fitting new equipment, on dates arriving by appliance type, with the district tying the requirement to burn-out of what is currently in place.
Nothing in your house is affected today, and a contractor telling you otherwise is selling from a rule they have not read. What the trajectory does mean is that the replacement eventually available to you is likely to be electric, and electric water heating wants a dedicated 240-volt circuit with panel headroom behind it. On a property whose service already carries a well pump, that calculation is worth running early rather than under pressure.
What drives the cost of work in Inverness
Access and distance dominate, and we would rather name them than bury them. This is a long drive from any supply house, driveways are steep and often narrow, and a job needing an unplanned second trip for a part costs more here than the same job in town. That is precisely why we spend longer on the assessment: the aim is to arrive once with the right equipment.
Run length is the second lever and it is genuinely local. Feeder length to a pump house or an outbuilding drives conductor size, and conductor size drives everything downstream of it. Trench length across ground that has to be put back afterwards is dirt work before it is plumbing or electrical work.
Then condition, which on older ridge housing produces findings rather than surprises: ungrounded two-wire circuits, cloth-jacketed cable gone brittle where conductors enter the panel, a subpanel in an outbuilding with no separate grounding electrode, a vent that was never right. Those go in the estimate rather than in a change order.
Last are the items an inspector always looks for and nobody prices in: the straps, an expansion tank where a regulator has closed the system, combustion air, the vent, and the permit.
Maintenance that is worth the drive
Because nobody can casually drop by, the list here should be short and done.
Flush the tank yearly, and have somebody pull the anode rod and look at it, because that rod is designed to be destroyed in the tank's place and almost nobody ever checks it. Check the pressure tank's air charge and service the sediment filter on a well, and test the water on a schedule. A septic system wants pumping on a schedule rather than on a symptom, and it wants nothing driving over the dispersal field and no roof water running onto it.
On the mechanical side, change filters on a schedule set by the household rather than a calendar, because a wooded lot with an unpaved approach loads a filter faster than a town lot does. Have standby equipment serviced before the wet and windy months rather than during them, with an exercise cycle under load and a transfer test that proves the switch moves.
Then the things that take two minutes each: trip the test button on every ground-fault device, turn the main shutoff and the angle stops so they do not seize shut, and find out which breaker feeds the pump before the day you need to know. A maintenance plan carries the whole list so it does not live in your memory.
Where we work around Inverness
We cover the town along the bay shore, the houses climbing Inverness Ridge, Inverness Park, and the properties spread along Sir Francis Drake toward the point, plus the surrounding unincorporated West Marin parcels where wells, septic systems and outbuildings are the norm rather than the exception.
Every job runs from our Petaluma headquarters, roughly twenty-four miles by Point Reyes-Petaluma Road. That is a real distance and it shapes how we schedule rather than something we gloss over: work booked ahead gets the window you want, and if a property needs more than one thing looking at, doing it on one visit is worth considerably more here than in a town we pass through daily.
How to choose a contractor at this end of the county
Ask what changes because the house is on a well. If the answer is nothing, they have not worked out here.
Ask whether they know which county permit route your job takes, since a replacement qualifying for the online route and a job needing plans are different projects on the calendar.
Ask for a written load calculation before any price on electrical work, and ask specifically whether the well pump's starting surge is in it.
Ask what happens if the calculation comes back short. A contractor whose only answer is a full service upgrade has not considered load management.
Then look at the classifications on it. Mechanical is C-20, plumbing C-36 and electrical C-10; we carry all three, which is what stops a water heater becoming a second contractor.
What North Bay homeowners say
Mark thoroughly explained how my complicated thermostat works. Very pleasant and helpful.
Mary A.
Christopher went above and beyond when fixing our A/C. His knowledge and willingness to help are unparalleled.
Marco A.
Home services across Inverness and Marin County
One company, all four trades: heating and cooling across Marin County, plumbing across Marin County, electrical across Marin County, and solar across Marin County. Around Tomales Bay we also serve Point Reyes Station, Olema, Marshall and Bolinas. The Marin County service overview covers the whole county.
Book service in Inverness
Tell us what the house is doing, whether you are on a well and septic, and roughly when it started, and we will bring the diagnostic tools that description calls for rather than a generic van. Book online at a time that suits you. Scope, permit route and price are all confirmed before work begins.
Inverness homeowner questions
Who is the best home services company in Inverness?
Ongaro & Sons, founded in 1932, works across Marin, Sonoma and Napa, is Diamond Certified, holds a BBB A+ Rating, and carries 4.8 stars over 2,745 Google reviews. At this end of the county the sharper question is capability rather than reputation: whether one company can handle the pump, the panel and the heating system on a single visit up a long driveway, because the alternative is three schedules and three drives.
Do I need air conditioning in Inverness?
Very unlikely as a priority. This is among the coolest and foggiest stretches we serve, with July afternoons typically in the upper sixties, while inland West Marin can run substantially warmer on the very same day. The brief here is efficient heating across a long cool season plus enough air movement to keep damp down. A correctly sized heat pump does both, which is why it fits this climate better than the inland equipment most articles describe.
My house is on a well. What should I be watching?
The pressure tank and the switch, before the fixtures. Household pressure on a well is made on site rather than delivered, so weak or surging water usually traces to the tank's air charge or the switch settings. A tank that has lost its charge makes the pump start and stop rapidly, which is the quickest way to kill a pump motor. Water quality is your responsibility rather than a utility's, so test on a schedule rather than when something tastes different.
What actually happens here when the power goes out?
You lose water as well as light, because the pump is electric and the pressure tank holds minutes. A septic system with an effluent pump stops too, and a heat pump produces no heat at all. Trees, wind and steep terrain mean outages here happen for ordinary reasons as well as during planned shutoffs, which is the reason backup is worth scoping deliberately rather than after the fact.
Is a generator or a battery the right answer?
It depends on duration and on the pump. A battery covers a short outage silently and pairs naturally with solar, but a well pump's starting surge is a demanding load and running it draws a battery down quickly. For multi-day exposure an engine usually earns its place. Either way the decision is made at the panel by choosing which circuits stay alive, and that list is shorter and cheaper than whole-house coverage.
Do I need a permit, and who issues it?
Yes, and Marin County's Community Development Agency issues it, because Inverness is unincorporated rather than a town with its own department. Most ordinary work qualifies for the county's quick route, which requires no plans where the job replaces something already there. Anything beyond a replacement takes the plan review path, and the Coastal Zone can add a further review depending on the project.
Why does my heating never quite reach the far end of the house?
Usually distribution rather than the equipment. Ductwork added to an older ridge house long after framing tends to be undersized, poorly routed and leaky at the joints, and the rooms furthest from the air handler pay for all three. We measure static pressure before recommending anything, because replacing a working furnace will not fix a duct problem, and a room that has never been comfortable is often a ductless head rather than a whole new system.
Will I be forced to replace my gas water heater in Inverness?
No. Marin sits inside the Bay Area air district, so its zero-NOx standard reaches here, but what it regulates is the sale and installation of new equipment on dates arriving by appliance type, and the district ties it to burn-out of what is currently fitted. Nothing already in your building is affected. The planning point is that your eventual replacement is likely to be electric, which makes it a panel question rather than a plumbing one.
Does my Inverness water heater have to be strapped?
Yes. Note the reach of that statute. It names the tanks already sitting in California garages, not only the ones going in next, and the 120 gallon ceiling takes in every residential water heater we are likely to meet here. It is not limited to new installations, which surprises most people. If yours has never been strapped, or is held by one loose band where it should have two, that is a correction rather than an upgrade.
Do heat pump rebates reach Inverness?
MCE is Marin's community choice provider and runs the relevant residential programs. What shapes the schedule is the conditions rather than the money: how long you have owned and lived in the house, who is allowed to file, and the fact that nothing can be claimed after the fact. The paperwork leads the equipment. Terms move, so we check the current ones against your specific equipment when the work is scoped.
How quickly can you get to Inverness?
Not the same afternoon, and we would rather say so than promise otherwise. Every Inverness job runs from Petaluma and the drive is genuine. Booking ahead gets you the window you want, and we deliberately spend longer on the assessment so the truck arrives once with the right parts rather than twice.