The Bay Area Gas Appliance Phaseout Is Coming to Concord and Contra Costa: What Rental Property Owners Need to Know
How Bay Area Air Quality Rules Will Reshape Water Heater and Furnace Replacements in Concord, Contra Costa County, and Beyond
California rental housing providers are used to a moving regulatory target — but for owners in Concord and across Contra Costa County, one change is no longer a distant "what if." The Bay Area Air Quality Management District (BAAQMD) has adopted rules that will gradually require water heaters and furnaces to meet zero-emission (zero-NOx) standards when they are replaced, and the first deadlines arrive as soon as 2027.
Unlike some air-quality rules that apply only in other parts of the state, these standards cover the entire Bay Area Air District — which includes all of Contra Costa County. If you own or manage rental property in Concord, Walnut Creek, Antioch, Pittsburg, Richmond, or anywhere else in the county, this rule will eventually shape how and when you replace major heating equipment.
Here is what property owners in our region need to understand.
What the Bay Area's Gas Appliance Rules Actually Require
BAAQMD's Regulation 9, Rules 9-4 and 9-6 set "zero-NOx" (zero nitrogen-oxide) emission standards for two of the most common systems in any rental property: space heating (furnaces) and natural gas water heaters.
A few points matter for how this plays out in the real world:
The rules apply at replacement, not immediately. There is no requirement to rip out a working furnace or water heater. The standard applies when a unit is newly installed — typically when an old one fails and needs to be replaced.
"Zero-NOx" effectively means electric. Because burning natural gas produces nitrogen oxides, meeting a zero-NOx standard generally points toward electric equipment such as heat pump water heaters and heat pump HVAC systems.
It governs what can be sold and installed here. Once each deadline hits, only zero-NOx versions of that appliance type can be sold or installed within the Bay Area Air District.
The Compliance Timeline
The standards phase in by appliance type and size:
January 1, 2024: New residential central furnaces already must meet an interim ultra-low-NOx standard (in effect now).
January 1, 2027: Smaller residential water heaters (under 75,000 BTU/hour) must be zero-NOx.
January 1, 2029: Residential and commercial furnaces must be zero-NOx.
January 1, 2031: Larger commercial and multifamily water heaters (roughly 75,000 to 2 million BTU/hour) must be zero-NOx.
For most single-family and small multifamily rentals in Concord and Contra Costa, the 2027 water heater deadline is the first one to plan around — and as of today it is only months away. As noted below, it is also the deadline most likely to shift.
Important: The Timeline Is Still Moving
This is where staying informed really matters. BAAQMD's Board of Directors is actively considering "flexibility amendments" in 2026 that could adjust the schedule and potentially push some compliance deadlines later. The smaller-water-heater requirement — the 2027 date — is specifically under review, with draft amendments circulating as recently as mid-2026.
In other words, the destination is fairly clear, but the exact dates and details are not yet locked in. These rules have also met real resistance elsewhere in California. In June 2025, the Southern California air regulator, the South Coast Air Quality Management District, narrowly voted down a proposed phaseout of gas furnaces and water heaters in homes, after the California Apartment Association and others argued the rules were preempted by federal law and the U.S. Attorney for the region warned of a potential lawsuit. A separate 2024 zero-NOx rule from South Coast, covering commercial and multifamily buildings, remains in effect but is now itself the subject of a federal lawsuit. Southern California regulators are expected to revisit a modified version, so the direction has not changed, but the episode shows how contested and fluid these appliance mandates still are. Owners who track these developments — rather than assuming the calendar is fixed — will be in the best position to time replacements wisely.
Who's Covered: Concord, Contra Costa, and the Fairfield Question
The Bay Area Air District spans nine counties: Alameda, Contra Costa, Marin, Napa, San Francisco, San Mateo, and Santa Clara in full, plus the southwestern portion of Solano County and the southern portion of Sonoma County.
What that means for the areas we manage:
Concord and all of Contra Costa County are fully within the district. These rules apply to your properties here.
The Fairfield area is a boundary case. Only the southwestern portion of Solano County — the Vallejo and Benicia area and communities along the county's southwestern edge — falls inside the Bay Area Air District. Fairfield sits right near that dividing line: parts of the greater Fairfield area may fall inside the district, while the rest of Fairfield, along with Suisun City and Vacaville, falls under the separate Yolo-Solano Air Quality Management District, which has not adopted these appliance standards.
Because the district line runs through the greater Fairfield area, the safest move for any property near that boundary is to confirm which air district governs the specific address before planning an equipment replacement.
Infrastructure Costs Can Extend Well Beyond the Appliance
Switching a water heater or furnace from gas to electric is often not a simple one-for-one swap. Depending on the property, a heat pump conversion can involve:
Electrical service or panel-capacity upgrades
New wiring or dedicated circuits
Equipment relocation (for example, moving a water heater out of a tight closet)
Ventilation or condensate changes
Broader mechanical redesign in older or multifamily buildings
These supporting improvements can cost more than the appliance itself. The owners who fare best are the ones who understand their properties' electrical capacity before an appliance fails — not in the middle of an emergency replacement with a tenant waiting for hot water.
Plan Capital Improvements Around the Timeline
Water heaters and furnaces are long-lived assets, and replacement decisions made today will bump up against these deadlines. A water heater installed now may well need replacing right around the 2027 or later compliance window.
Practical steps for Concord and Contra Costa owners:
Inventory the age and condition of heating and water-heating equipment across your portfolio.
Flag units likely to fail near a compliance deadline so a compliant replacement is not a surprise.
Budget for possible electrical upgrades, not just the appliance.
Weigh long-term operating costs — heat pump equipment is typically far more energy-efficient — when selecting new systems.
Don't Overlook Available Incentives
Because these rules push toward electric equipment, a range of rebates and incentives can offset upgrade costs for heat pump water heaters and HVAC systems. Statewide and regional programs — such as those listed through California's Switch Is On and regional energy programs like BayREN — are worth checking before any major replacement, since incentives can meaningfully change the math on a conversion.
Why Professional Property Management Matters Here
In California, owning rental property has always meant more than collecting rent. Rules like these reward owners who plan ahead and cost owners who react late. Strong property management means staying on top of:
Evolving regulatory and compliance deadlines
Equipment age tracking and proactive replacement
Vendor coordination and permitting
Capital-improvement scheduling and budgeting
Available rebates and incentives
Long-term asset preservation
The goal is simple: replace equipment on your schedule and budget, with the right compliant system and any incentives you qualify for — not scramble after a failure to find that the rules, the equipment options, and the costs have all changed at once.
The Bottom Line for Concord and Contra Costa Owners
The Bay Area's gas appliance phaseout is not a someday story, and unlike Southern California, it has not stalled — it applies here in Contra Costa County, and the first deadlines are close. The exact schedule may still shift as BAAQMD weighs flexibility amendments in 2026, but the direction is set, and the owners who plan now will avoid the cost and stress of reacting later.
At Legacy Property Management, we help rental property owners across Concord, Contra Costa County, the greater Fairfield area, and throughout Northern California stay ahead of changing regulations — tracking compliance timelines, planning equipment replacements, and protecting the long-term performance of their investment properties through proactive, informed management.
