If your mid-century house has a brick or block fireplace, the wood burning fireplace rules Bay Area air regulators set apply every time you light it, remodel it or sell the house. They come from one regulation, the Bay Area Air District's Regulation 6, Rule 3, which the Air District's board last amended on October 1, 2025.
This guide covers Spare the Air no-burn days, the narrow exemptions, the $15,000 remodel trigger, the ban on wood-burning devices in new construction, EPA-certified stoves and gas inserts, and the disclosure you give a buyer. It's based on the rule text and the Air District's wood smoke pages, read in November 2026.
What Regulation 6, Rule 3 covers
Rule 6-3 was adopted in July 2008 and amended in 2015, 2019 and 2025; the October 1, 2025 version is current as of November 2026. It applies to any wood-burning device in the Air District, which the rule defines as any wood heater, fireplace, or indoor permanently installed device used to burn solid fuel for heat or for looks. That includes masonry and factory-built fireplaces, wood stoves, pellet stoves and wood-burning inserts. Solid fuel includes manufactured logs and pellets, so a store-bought log counts as burning.
Outdoor fire pits, chimineas and outdoor fireplaces aren't covered by Rule 6-3, and the Air District's FAQ (updated February 2020) says new ones don't have to be EPA-certified. But Regulation 5, its open burning rule, bans recreational fires during a Mandatory Burn Ban (section 5-302), and the FAQ says that covers outdoor fireplaces, fire pits and chimineas.
Spare the Air no-burn days
Section 6-3-301 makes it illegal to burn wood or any solid fuel in a wood-burning device during a Mandatory Burn Ban, which the Air District announces through a Spare the Air Alert. As of the October 2025 amendments, a ban is called when the 24-hour average of fine particle pollution (PM2.5) is forecast to exceed 25 micrograms per cubic meter anywhere in the Air District. The old trigger was 35. Air District staff estimated the change could raise the number of no-burn days from an average of 15 a year to between 19 and 41.
The Air District's wood smoke page says bans apply year-round, including when wildfire smoke drives up fine particles. Its FAQ says the forecast comes out by 2 p.m., and a ban covers the whole next day, midnight to midnight. Check the Spare the Air website or app, or sign up for alerts.
On enforcement, the February 2020 FAQ says an inspector has to observe the violation. A first violation brings a $100 fine, and violators may get a one-time option to take the Air District's wood smoke awareness test instead. A second violation brings a $500 fine, and repeat violations bring higher penalties. The Air District's current wood smoke page gives no amounts, so confirm current penalties with the Air District.
Exemptions are narrow
Rule 6-3 has three limited exemptions, all subject to verification:
Sole source of heat (6-3-110). You can burn during a ban only if your sole source of heat is an EPA-certified device registered with the Air District and you have no permanently installed gas, propane or electric heat. An open hearth fireplace never qualifies. Registration lasts five years, and you renew before it expires.
Broken heater (6-3-111). If your only installed heater stops working, you can get a 30-day exemption while it's repaired, with repair records sent to the Air District within 10 days of a request.
Utility outage (6-3-112). A temporary loss of gas or electric service, with no other heat available.
The Air District's exemption guidance (March 2020) lists radiant heaters, wall heaters, baseboard heaters and central furnaces as permanently installed heat. So if your Eichler still has working radiant floor heat, the fireplace isn't your sole source of heat, even if the radiant system doesn't warm the whole house. A portable electric heater doesn't count against you. Rental properties in areas with natural gas service must have permanently installed heat that doesn't burn solid fuel, and they can't use the sole-source exemption.
Remodeling a fireplace or chimney
Section 6-3-307 is the rule mid-century owners run into during a renovation. You can't remodel a fireplace or chimney unless you install a gas-fueled, electric or EPA-certified device. The rule defines a remodel as a change to the appearance or functional utility of a fireplace or chimney that requires a building permit, and the requirement applies when the total cost is more than $15,000, not counting the permit fee.
Under that wording, a permitted fireplace or chimney remodel costing more than $15,000 has to end with a gas, electric or EPA-certified device, and work under that amount, or work that doesn't need a permit, doesn't trigger this section. The rule doesn't say whether a particular job, such as rebuilding a damaged chimney to match, counts as a remodel, so ask the Air District and your city building department before you sign a contract. If the chimney work is seismic, our post and beam earthquake retrofit guide covers who should assess a masonry chimney. Taking a chimney down also counts as demolishing a load-supporting member under the Air District's asbestos rule, as our asbestos survey guide explains.
New construction, additions and ADUs
Section 6-3-306 bars installing any wood-burning device in new building construction, which the rule defines as a housing unit whose construction began on or after November 1, 2016, counted from when the foundation was installed. The FAQ says that includes fireplaces, EPA-certified wood stoves and inserts, and pellet devices; gas and electric devices are allowed. The rule doesn't say whether a detached ADU counts as new building construction. Since the definition covers any housing unit whose foundation went in on or after that date, ask the Air District before planning a wood-burning device in an ADU.
Choosing a device: EPA-certified, gas or electric
Under section 6-3-303, any wood-burning device sold or installed in the Air District must meet the federal standards in 40 CFR Part 60, Subpart AAA, which is what "EPA-certified" means in the rule. That doesn't apply to a device that's an installed fixture in a house being sold. A certified heater can be freestanding, built in or an insert in an existing fireplace.
The EPA's Burn Wise pages add practical points, though the EPA notes the program ran from 2009 to 2025 and the pages haven't been updated since October 30, 2025:
An insert goes inside the firebox of an existing masonry or metal fireplace, and a certified installer should make sure the flue liner in a masonry chimney is installed correctly.
A factory-built, or zero-clearance, fireplace needs an insert designed and tested for that unit.
The EPA calls fireplaces typically very inefficient heaters, and says a properly installed and operated fireplace retrofit device can cut pollution by approximately 70%.
Gas stoves can vent through an existing chimney or directly through a roof or wall. The EPA doesn't support unvented gas models, citing indoor air quality, and says some places don't allow them.
Gas and electric devices aren't subject to burn bans. The Air District's zero-NOx appliance rules apply to furnaces and water heaters and no other natural gas appliances. The Air District's wood smoke page says it periodically offers grants to replace a wood-burning device with a heat pump.
Burning when it's allowed, and selling the house
On days without a ban, section 6-3-308 limits visible smoke from a wood-burning device to No. 1 on the Ringelmann chart, or 20 percent opacity, for no more than 3 minutes in any hour, with up to 20 minutes allowed when starting a fire, once in any four-hour period. Section 6-3-309 bans burning garbage, treated or painted wood, unseasoned wood, used pallets, plastic, glossy or colored paper, saltwater driftwood and particle board. Seasoned wood has 20 percent moisture or less. The EPA's Burn Wise pages say fire officials recommend a professional inspection of the appliance, chimney and vent every year.
When you sell or rent out a house with a wood-burning device, section 6-3-304 requires a disclosure of the health hazards of wood smoke. The Air District updated its Residential Wood Burning Disclosure on October 1, 2024, and says transactions after January 1, 2025 must use the updated form, signed and dated by the buyer or renter. Rule 6-3 doesn't require removing the fireplace before a sale. The Air District's historic table of local wood smoke ordinances lists Palo Alto, Mountain View, Sunnyvale, Los Altos and San Jose, with provisions such as a ban on new masonry fireplaces or on converting a gas fireplace to wood, and warns that some listed provisions are no longer valid. We didn't check those cities' current codes, so check your own city's. Our guide to California home sale requirements covers the carbon monoxide alarms a house with a fireplace needs.
This is general information as of November 2026, not legal advice. Air District rules and Spare the Air thresholds change, so confirm current requirements with the Air District and your city building department, and use a licensed contractor or certified installer for any insert or chimney work.
Frequently asked questions
Can I use my fireplace on a Spare the Air day?
Not if a wood-burning ban is in effect, unless you qualify for one of the three exemptions. That includes manufactured logs and pellets. A gas or electric fireplace can still be used.
Can I put a gas insert in my original fireplace?
Rule 6-3 allows it: the rule treats gas-fueled inserts and fireplaces as gas-fueled heating devices, which aren't subject to burn bans. Ask your city whether the work needs a permit, and if it's part of a fireplace remodel over $15,000 with a permit, the new device must be gas, electric or EPA-certified anyway.
Do I have to remove a wood-burning fireplace before I sell?
Not under Rule 6-3; its device standard doesn't apply to an installed fixture sold with the house. You do have to give the buyer the Air District's wood burning disclosure. Check whether your city has its own ordinance.
Are outdoor fire pits allowed on no-burn days?
No. Regulation 5 bans recreational fires during a Mandatory Burn Ban, and the Air District's 2020 FAQ says that includes outdoor fireplaces, fire pits and chimineas. Barbecues are allowed.
Related reading
Heat Pumps for Mid-Century Homes: Going All-Electric in the Bay Area
Eichler Radiant Heat: Copper vs. Steel, Repair, Replace or Retire
Insulating an Exposed Beam Ceiling: Above the Deck, Edges and Walls
More guides on this topic: Owning & Renovating a Mid-Century Modern Home
Weighing a fireplace remodel, or selling a mid-century house with its original hearth? Call or text the Boyenga Team at Compass at (408) 373-1660 or (650) 383-8606, or contact the Boyenga Team to talk through the house before you start.
