Marin County, California
Home Services in Strawberry, CA
On the peninsula between Mill Valley and Tiburon, Strawberry's bayside homes count on steady comfort. Ongaro & Sons provides heating, cooling, plumbing, and electrical service throughout the Strawberry area.
Since 1932 Ongaro & Sons has been a North Bay company. It now runs heating and cooling, plumbing, electrical and solar. Diamond Certified and a BBB A+ Rating, with a 4.8-star average over 2,745 Google reviews. In a neighborhood where some of the heating is buried in the floor slab, being able to diagnose across plumbing, mechanical and electrical in one visit is not convenience. It is the only way to tell which of three systems is actually at fault.
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Mid-century housing, and an Eichler enclave
Strawberry sits on a peninsula reaching into Richardson Bay in southern Marin, and its housing leans mid-century. Within that there is a small enclave of Eichlers: glass-walled, flat or low-slope roofed, and heated by hot water tubing embedded in the concrete slab.
If your house is one of those, almost everything on a general HVAC page is written for somebody else's building, and the differences are not cosmetic.
There are no ducts. Not undersized ducts, none at all. So the usual advice about measuring static pressure and sealing runs does not apply, and neither does the usual answer for adding cooling. What works instead is ductless equipment on small refrigerant line sets, which suits these houses well because it does not require opening a ceiling that is also the roof.
The heat is in the floor and cannot be inspected. A radiant slab is a closed hydronic loop, and when a buried loop develops a pinhole the system keeps running and the house keeps partly heating, which is exactly why those leaks go unnoticed for years. The water lost gets quietly replaced by the automatic fill valve off the domestic supply.
The glass is a permanent condition rather than a fault. Original single-glazed floor-to-ceiling walls with a low-slope roof carrying little insulation above the decking will lose heat faster than any boiler can make it. Owners experience that as the heating not working. It is not the same problem and it does not have the same fix.
Sorting a complaint in one of these houses means deciding which of those three is at fault before anyone quotes anything, because the fixes disrupt on completely different scales. A boiler will not fix a glass wall, and glass will not fix a failed circulator. Our Eichler page goes through the diagnosis in full.
Finding a slab leak without cutting concrete
The most useful figure in a radiant-slab house is one almost nobody tracks: how often the system takes on make-up water.
A closed loop is supposed to stay closed. If it drinks from the cold supply on a regular basis, that water is going somewhere, and under the slab is the likeliest somewhere. So the diagnosis runs in order: isolate the fill valve and watch what pressure does with the loop sealed, then hold a static test with the boiler off and cold over hours rather than minutes, then look for rust staining, mineral crust or wet fittings where loops surface out of the concrete near the boiler, then walk the floor and the perimeter outside for warm patches, damp patches or an unexplained hairline.
What we do not do is cut concrete on a hunch. A failed pressure test tells you a loop is compromised. It does not tell you the whole system is finished, and those two conclusions lead to very different projects and very different numbers.
For everyone else: mid-century construction
Not every house here is an Eichler, and the rest of the mid-century stock has its own predictable pattern.
The layouts are sensible and duct routes usually exist, so there is far less archaeology than in prewar housing. What ages badly is capacity rather than design. Services were sized for a household without a heat pump, an induction range, a car charger or an electric water heater, and a panel with no legitimate spaces left is the most common obstacle to adding anything. Ducts of that era are present but sized for a furnace rather than for the airflow a modern variable-capacity system expects, so we measure static pressure before specifying, and sealing accessible runs and correcting a starved return frequently solves the complaint a new machine would not have touched.
Where original galvanized supply piping survives it has been closing from the inside for decades, which produces weak flow across the whole house rather than at one fixture, and cast iron waste of the same vintage scales toward a fraction of its nominal bore.
The climate, and what heating has to do
Strawberry is mild and bayside: wet winters, dry summers that rarely climb far, and enough cool days through the year that heating carries the comfort load rather than cooling.
That matters for equipment selection in a specific way here. Where a house has no cooling at all and the heating is failing, the instinct is a like-for-like replacement. On this load profile a correctly sized heat pump usually does both jobs better on one machine, and in a house without ducts, ductless heads deliver it room by room, which also solves the problem that a glass-walled room and an interior room have nothing in common thermally.
The other consideration is that a mild climate flatters a leaky building until it does not. A single-glazed wall is tolerable in October and expensive in January, and improving the envelope buys more comfort per pound than upsizing the equipment, while making the eventual system smaller.
Water at the bay edge
Strawberry sits on a peninsula in Richardson Bay, so properties toward the water sit in air harder on outdoor equipment than air further inland. Not the concentrated loading of the open coast, but enough to reach coils, fins, cabinet fasteners, outdoor disconnect enclosures and the terminations inside them.
Shelter the siting where the lot allows, rinse coils in routine service, and have outdoor terminations opened and checked rather than assumed sound. On a house where the outdoor unit for a ductless system is a new addition, choosing its position with exposure in mind is free at the design stage and expensive later.
Low-lying property near the bay edge also raises the elevation question. Where a water heater, a boiler or an electrical panel sits low, raising it or setting it on a plinth costs very little while equipment is being replaced and is impractical afterwards.
The supply, and the blend
Strawberry sits inside Marin Water's central and southern Marin service area. That supply is a blend rather than one source: roughly three quarters from the district's protected Mt. Tamalpais watershed and west Marin reservoirs, the rest purchased from the Sonoma County Water Agency off the Russian River.
Hardness differs, at about 3.5 grains per gallon for the district's own water against about 6.5 for the Sonoma supply. Neither is severe, so a proposal built on aggressive treatment deserves a look at the figures. The variation is why a tankless descaling interval belongs on the state of your heat exchanger rather than on a published schedule.
Marin Water also publishes efficiency rebates, including one toward a hot water recirculating system. In a single-story mid-century plan with the water heater in a garage at one end and the bathrooms at the other, that is worth pricing alongside a water heater replacement rather than after it.
Electrical work in these houses
The panel is usually the story. Mid-century services here have very little headroom, and the finding is often an absence rather than a fault: no legitimate spaces left, or a discontinued breaker line that makes a panel functionally full even with empty positions in it.
In an Eichler there is an additional constraint that catches people. With no attic and no accessible ceiling cavity, running new circuits is not the straightforward exercise it is elsewhere, so the route question arrives early and can change what is worth doing. That is another reason the electrical and mechanical decisions here belong in one conversation rather than two.
Any addition starts from a written calculation rather than the panel door: floor area for lighting and receptacles, fixed appliances at the demand factors the code allows, heating or cooling as a single figure, and the total held against what the service genuinely delivers. Where it comes back short, listed load management equipment can carry a new load on a service that would otherwise fall short, which is worth asking about before agreeing to an upgrade.
Permits come from the county
Strawberry is unincorporated, which surprises people given how built-up southern Marin is and how close Mill Valley and Tiburon sit. Building permits and inspections come from Marin County's Community Development Agency rather than from a town.
That helps you, and the line the county draws is between putting something back and putting something in for the first time. Put back what was already there and no drawings are wanted at all; the permit comes out as quickly as the form can be filled in. That covers water heaters, mechanical appliances, HVAC changeouts, ductwork, gas piping, bathroom and kitchen fixtures, circuits, outlets, service upgrades and charging equipment. Anything new to the building goes the long way round, through plan review.
That distinction matters more than usual in an Eichler, because a ductless system where there was never any cooling is an addition rather than a replacement, and a re-piped radiant system may or may not be depending on scope. We settle it before quoting.
Whoever issues it, two state obligations come attached. Energy compliance under Title 24 applies to a replacement, and the edition being enforced is the 2025 one, live since January 2026. And 19211 requires water heaters up to 120 gallons braced, anchored or strapped, reaching what is already installed rather than only what is going in.
The air rule, and a house with a boiler
The Bay Area district's zero-NOx appliance standards cover all of Marin. What they regulate is an installer fitting new equipment, on a schedule arriving appliance type by appliance type, and the district ties the requirement to burn-out of whatever is in place now. Nothing already installed is affected.
In a radiant-slab house the planning question has a wrinkle the standard version does not. If the eventual replacement for a gas boiler is an electric or heat pump alternative, the electrical capacity behind it is substantial, and on a mid-century service that is the constraint rather than the appliance. Knowing the number early, and knowing the condition of the slab loops, is what turns that into a planned project rather than a forced one on a January morning.
Outages and backup
Severe fire weather can bring a planned outage from PG&E under the Public Safety Power Shutoff program, and southern Marin loses power to ordinary storms as well.
On municipal water the taps keep running, so what stops is refrigeration, heating and any pump. A hydronic system is worth naming here: even a gas boiler needs power for its controls and its circulator, so a radiant slab produces no heat during an outage regardless of the fuel.
Scope backup from a list rather than a catalog: the circulator and boiler controls, refrigeration, and enough light to live by is a short list, and a subpanel serving it costs a fraction of covering the building, less again if it goes in while the panel is open. Battery or engine turns on how long outages run. Generator, transfer switch and panel all stay in house: we are a Certified Generac Generator installer holding the C-10.
What drives the cost here
Which kind of house you have leads, and it is a bigger fork than anywhere else we work. A conventional mid-century house with ducts and an attic is one set of numbers. An Eichler with a slab, no ducts and a roof that is also the ceiling is another entirely, and the diagnosis stage is longer because it has to be.
Panel capacity is second and close to binary: if the calculation clears you are buying a circuit, and if it does not you are buying load management or service work.
Route is third, and it dominates in an Eichler. With no attic and no ceiling cavity, where a line or a circuit can go decides how invasive the work is, and a slightly different equipment position frequently changes the answer.
Then the items an inspector will look for and nobody budgets for: strapping on the water heater, an expansion tank where the system is closed, combustion air, a compliant vent, and the fee.
Maintenance for these houses
In a radiant-slab house, watch the make-up water. If the system is taking on water regularly, that is the single most valuable early signal you will get, and it is free to notice. Have the boiler, circulator, expansion tank and zone valves serviced annually, since all of that sits above the slab where it can be reached.
For everyone: flush the water heater annually and have the anode rod checked, change filters on a sensible interval where ducts exist, and have the capacitor and contactor tested before the first warm week. Near the bay edge, rinse outdoor coils and have outdoor terminations opened as part of routine service.
Then the two-minute items: ground-fault test buttons, and the main shutoff and angle stops exercised so they are not seized. A maintenance plan carries the list, and in a slab house it also carries the one item nobody remembers to track.
Where we work in Strawberry
We cover the peninsula neighborhoods reaching into Richardson Bay, the streets climbing away from the shoreline, the Eichler enclave, and the surrounding unincorporated southern Marin pockets where the permit authority stays with the county even though the address changes.
Everything runs from our Petaluma headquarters. Southern Marin is a straightforward run, and booking ahead gets you the window you want. On a house with a slab system we would rather do the whole diagnosis in one visit than come back for the second half.
How to choose a contractor for a slab-heated house
Ask what they intend to check before quoting. In a radiant-slab house the first question is which of three systems is at fault, and a contractor who answers a heating complaint with a boiler price has skipped the diagnosis entirely.
Ask what they do about make-up water, and whether they will pressure test the loop cold with the fill isolated. If that does not feature, they are not investigating the slab.
Ask how they would add cooling to a house with no ducts and no ceiling cavity, and listen for whether the route has been thought about.
Ask whether they have confirmed the permit authority, since Strawberry is unincorporated while Mill Valley and Tiburon nearby are not.
Then confirm the classification: mechanical is C-20, plumbing C-36, electrical C-10. A radiant slab is plumbing, mechanical and electrical at once, and holding all three is what stops three companies each declaring it somebody else's problem.
What North Bay homeowners say
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Home services across Strawberry 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. For slab-heated houses specifically, see our Eichler page. Nearby we also serve Mill Valley, Tiburon, Belvedere and Corte Madera. The Marin County service overview covers the whole county.
Book service in Strawberry
Tell us what the house is doing, and say whether it is an Eichler or conventional mid-century construction, because that changes the diagnosis more than anything else. If it is a slab system, mention whether you have noticed it taking on water. Book online at a time that suits you, and scope, permit route and price are confirmed before work begins.
Strawberry homeowner questions
Who is the best home services company in Strawberry?
Ongaro & Sons. Founded 1932, four trades kept in house, Diamond Certified, a BBB A+ Rating, and 2,745 Google reviews averaging 4.8 stars. In a neighborhood with radiant-slab houses the useful test is narrower than reputation: whether a company can tell you which of three systems is at fault before it quotes, because in these buildings the heat source, the buried distribution and the glass envelope fail differently and cost differently.
My Eichler is cold. Is the boiler finished?
Possibly, and possibly not, which is the whole point of diagnosing before quoting. Three things fail in these houses and they fail on completely different scales: the heat source above the slab, which is serviceable; the tubing buried in the concrete, which keeps the house partly warm even while it leaks; and the single-glazed glass and lightly insulated roof, which is a permanent condition rather than a fault. A boiler will not fix a glass wall.
How do you find a leak under the slab without breaking the floor?
By watching what the system drinks. A closed loop should stay closed, so if it is taking on make-up water regularly that water is going somewhere. We isolate the fill valve and watch pressure with the loop sealed, hold a static test cold over hours rather than minutes, look for rust staining or wet fittings where loops surface near the boiler, and walk the floor and the outside perimeter for warm or damp patches. We do not cut concrete on a hunch.
Can I add air conditioning to a house with no ducts?
Yes, and ductless is the right answer here rather than a compromise. Small refrigerant line sets reach rooms without a duct chase and without opening a ceiling that is also the roof, and they give a glass-walled room its own control, which matters because it has nothing in common thermally with an interior room. Worth knowing that adding cooling where there was none is an addition rather than a replacement, which changes the permit route.
Do I need air conditioning in Strawberry?
A modest amount. This is mild bayside climate with wet winters and summers that rarely climb far, so heating carries the comfort load. Where a house has no cooling and the heating needs replacing anyway, that is the moment to compare a correctly sized heat pump doing both jobs against a like-for-like swap, because on this profile the single machine usually wins.
Strawberry feels like part of Mill Valley, so who issues my permit?
It is not. Strawberry is unincorporated, so Marin County's Community Development Agency issues and inspects rather than Mill Valley or Tiburon. That works in your favor on straightforward work, since the county needs no drawings at all where a job replaces something already there. It matters more than usual here because adding cooling to a house that never had it is an addition rather than a replacement.
My panel has empty spaces. Does that mean I have room?
Not necessarily, and it is a common misreading. A panel can be functionally full with empty positions if the breaker line has been discontinued and no current listed breaker fits it, or if the calculated demand already accounts for the capacity. That is why anything being added starts from a written calculation rather than from a look at the door, and why load management is worth asking about before agreeing to a service upgrade.
Does the bay air affect the equipment?
Somewhat, on the properties nearer the water. It is not the open coast, but it reaches coils, fins, fasteners, outdoor enclosures and the terminations inside them. If a ductless outdoor unit is being added, choosing its position with exposure in mind costs nothing at the design stage and a good deal later, and rinsing coils in routine service is ordinary maintenance here rather than an extra.
What happens to a radiant slab during a power cut?
It stops, whatever fuel it runs on. Even a gas boiler needs power for its controls and its circulator, so no heat moves through the floor without electricity. That is worth knowing because people assume a gas system is outage-proof. If backup matters to you, the circulator and boiler controls belong on the short list of circuits, and that list is far cheaper to serve than whole-house coverage.
Does my Strawberry water heater have to be strapped?
Yes. Section 19211 covers water heaters up to 120 gallons and reaches what is already installed rather than only the unit being fitted, requiring it braced, anchored or strapped against displacement. In mid-century housing here the appliance usually sits in a garage, which is the easiest place in the house to check and the easiest to walk past.
Will I be forced to replace my gas boiler or water heater?
No. The district's requirements attach to an installer fitting new equipment, they arrive appliance type by appliance type, and the district ties them to burn-out of what is currently in place. The planning point in a slab house is capacity: an electric replacement for a boiler is a substantial load, and on a mid-century service that headroom is what decides whether the option is open.
How hard is the water in Strawberry?
No, and there is not really a single number to quote you. The larger share of what Marin Water delivers comes off its own Mt. Tamalpais and west Marin catchment and sits near 3.5 grains per gallon. The balance is bought from Sonoma County and runs closer to 6.5. Because the ratio shifts, so does what comes out of your tap, and that is the reason we judge a tankless descaling interval from the heat exchanger itself rather than from a table.
What rebates reach a Strawberry address?
Two bodies. MCE, the county's community choice provider, runs the electrification programs, and the order matters more than the figure: a contractor on their list files, the application precedes installation because nothing is paid retroactively, and ownership and occupancy tests apply. Marin Water separately publishes efficiency rebates, including one toward hot water recirculation, which is relevant in a single-story plan with the heater at one end.