Fireplace with Lone Hill Quarry Stone.pngMore likely than not, you either own or have shopped for Silicon Valley homes with fireplaces. In that case, you’ve likely also heard tale about the new law that would force homeowners to replace older fireplaces with new gas only ones or decommission them entirely before selling. Let me quash those rumors now – homeowners with wood-burning fireplaces do not automatically need to replace them at the sale of the property at this time. But what’s behind the rumor anyway?


A few years ago, there were proposed regulations in place that were going to make stipulations for home sellers with older fireplace in the San Francisco Bay Area. Amendments have since been made to the ordinance, removing this requirement. These were part of Regulation 6, Rule 3: Wood-Burning Devices, which was adopted in July 2008 to regulate and improve air pollution levels for the health of the Bay Area community (Wood Burning Regulation). Its immediate effect was to enforce Winter Spare the Air Alerts and Mandatory Burn Bans.

The regulation also stated numerous rules that would be effective at future dates (mostly beginning November 1, 2015/6), including many that will be passed this year and in the future, up to 2020. So, while you don’t need to worry about replacing your fireplace before you sell, there’s plenty to be aware of when you use, replace, repair, and install your fireplace – and you may still need to replace it.


Smokey sky from fire June 2008With 1.4 million woodstoves and fireplaces around the Bay Area, it’s no surprise they make up a major part in the region’s air pollution – approximately one third of winter pollution! That’s greater than the amount of pollution caused by vehicles. Burning solid fuels produces what is known as soot, or more scientifically, PM2.5, which stands for Particulate Matter with diameter of 2.5 microns or less (Ordinance). These particles in the air are a form of pollution which is so fine that when breathed in it can penetrate deep into the lungs and even enter the blood stream.

Wood smoke contains a group of compounds that are similar to second-hand cigarette smoke and are likewise hazardous (2012 flier). Studies show that this type of pollution can cause a variety of health conditions which can put undue stress on individuals with weak respiratory or cardiovascular systems.

Apparently 1 in 7 Bay Area residents has a respiratory condition, and these folks of course are more vulnerable to problems from pollution. Immediate effects might be watery eyes and coughing, while long-term exposure to polluted air can permanently harm lung function, capacity, and development – possibly instigating diseases like asthma and bronchitis. “Eliminating residential wood burning during a Winter Spare the Air Alert can reduce soot in the Bay Area by 35 tons each day” (Wood Burning Regulations Flier). On top of the particulate pollution, wood smoke also contains a variety of gases, including toxins like dioxin (Wood Burning Regulations Flier).

But why winter? What about summer barbeques? Weather is important in regard to the displacement of these polluters. Spare the Air Alerts are hardly ever called when it’s been raining. Cold, still weather conditions cause the smoky air to become trapped near the ground, allowing pollution to build up to unsafe levels (Flier). When a Spare the Air alert is not called but data indicates worsening conditions there may be an optional compliance health advisory in the form of a Recommended No-Burn Day. And as for summer barbeques – the weather conditions in summer are more prone to heightening levels of ozone than soot, so Summer Spare the Air Alerts are placed based on very different weather and pollution concerns.

Other than pollution, there are still plenty of reasons to not burn. Fires are not a very efficient form of heating, and many fireplaces actually rob your home of heat, sending hot air up the chimney and out of your home. Prevent heat loss (and the need to burn more fuel or crank the thermostat) by keeping your home well insulated and weatherized. Get more efficient heating with an EPA certified device or alternative natural gas or electric heater.

Law on wood burning

Fire Belgatos Park Los Gatos - wood burning, grass burning in the park - luckily no homes were harmed and it was contained quicklySo now that we understand the why, let’s look at what the law is and how you comply with it.

For nearly 20 years, Spare the Air (est. 1991) was a voluntary campaign established by the Bay Area Air Quality Management District (est. 1955). Unfortunately, this did not meet clean air standards, and the program became regulated in 2008.

“Because most air pollution is preventable, Spare the Air is focused on educating the public and promoting changes in behavior that will help prevent unhealthy air quality”  from the Spare the Air site.

When can you burn? Firstly, Winter Spare the Air Alerts can be called any time between November 1st through the end of February. The Air District announces an air quality forecast each day at 2pm for the following day. When the forecast is unhealthy, a Spare the Air Alert will be called and that day will have a 24 hour, day long, ban on wood burning.

In other words, any time during those four months you must check for a mandatory burn ban before you light a fire. The bottom of this page has a list of ways to check – any time there is a Winter Spare the Air Alert it is illegal to burn solids. Gas-only and electric fireplaces may still be run during Spare the Air Alerts.

Where can you burn? Currently, new construction allows EPA-certified wood- or pellet-burning devices to be installed. On November 1, 2016, the law changed to disallow the installation of any wood-burning devices in the Bay Area. New construction and renovations costing $15,000 or more, or which alters an existing firebox, will only allow gas and electric devices. Manufacturers, sellers, re-sellers, and installers must only sell and install certified devices, and provide information on burning operation and maintenance and documentation on certification to the customer.

Find a list of approved indoor appliances at the EPA website. The law does not stop you from using an older fireplace already installed, or for making minor repairs to it. Regulations on sold and installed devices will become stricter in 2020.

Also, outdoor wood-burning devices are not covered in these regulations. They do need the same certifications as indoor installations, but, as recreational devices, they are still subject to Winter Spare the Air Alerts. (Winter Spare the Air FAQs)

What can you burn? This is very important, because different types of fuel release different types, and levels, of pollution.

Clean, seasoned firewood, pellets and manufactured logs are allowed solid fuels. Firewood must be seasoned, and all firewood sold in stores must be labeled to indicate if it is seasoned or if it is unseasoned and how to season it. Seasoned firewood has lower moisture content (less than 20% by weight – other identifiers through the link) than unseasoned and burns more cleanly. Seasoned wood is also untreated wood. Wood that has paint or lacquer, or wood that has been chemically treated, such as fence posts are treated for weather and insect resistance, and salt-water driftwood are illegal to burn. Plastics and garbage are also illegal to burn and are dangerous.

How can you burn? Even when everything else is right, you can still break the law by burning improperly. The regulation has set in place a year-round ban on excessive chimney smoke with Visible Smoke Limits (photo examples are in link). If you can remember “20-20 vision,” you can remember this rule – after the first 20 minutes, starting up your fire, the smoke must impair less than 20% visibility of objects behind it. So start your fire and after 20 minutes go outside to check that it’s not more than 20% opacity. To avoid, burn clean, dry fuel in hot fires with lots of air circulation, and have your chimney inspected often. (For more, see the Wood Burning Regulation.)

Other regulations include disclosures. While sellers are not required to replace a fireplace, effective June 1, 2016, anyone who rents, leases, or sells their property must provide disclosure documents describing health hazards of wood burning and PM2.5 pollutions (Ordinance).

While sellers will not have to replace old devices, renters do.

Effective November 1, 2018, all real property offered for lease or rent in areas with natural gas service shall have a permanently-installed form of heat that does not burn solid fuel.” (Ordinance)

And of course, there are exceptions.


Outdoor fireplaces (not attached to a structure) do not need to follow the same regulations as indoor devices.

The Winter Spare the Air mandatory burn bans do not apply to devices which are primarily used to cook human food. While you can barbeque on a Spare the Air Day, it is best if you refrain, or choose cleaner options like a gas or propane barbeques.

It is also still legal to burn during an alert if you are the resident of a dwelling whose only source of heat is supplied through wood burning. However, “All residential properties claiming Only Source of Heat Exemption must have a registered EPA certified device,” (Amendments August 2015), effective November 1, 2016.

During a power outage, where alternative utilities are lost, the regulation allows for a limited exemption from the rules. (Winter Spare the Air FAQs)

Rural areas have their own exemption as well: residential or commercial buildings with no infrastructure for gas service in existence within 150 feet of the property line are exempt. (Ordinance No. NS-1100.90)

Homes (excluding commercial and rental properties) with permanent heating devices that fail to function may receive a 30 day exemption from mandatory burn band to complete repairs to their permanent heater.

Often, Santa Clara County residents may not understand the importance of “Spare the Air” days or the impact of smoke on the health of others – especially with those who have lung problems.  As we continue to clean up our air, it’s likely that wood burning fireplaces will go the way of the dinosaur.  While it’s sad to part with something that provides such beautiful, even “homey” sights, smells, and sounds, in time I believe it will get to be the new norm.  Eventually the public sentiment will swing such that those who do burn will likely be frowned upon, not unlike those who play their car radios too loudly and disturb the neighbors to the point of annoyance.  We are not yet there – but it’s good to begin with small steps to cut back on wood burning for everyone’s better health.

Check Before You Burn:




Residents in particular circumstances may be eligible for PG&E Financial Assistance Programs for help in the payment of utility bills.

A brief of the Wood Burning Rules are here.

Read more about the BAAQMD plans here.

Find more details on regulations for wood burning appliances here, at the EPA website.

Santa Clara County BAAQMD

California Environmental Protection Agency Air Resources Board

North American Studies on the Health Effects of Woodsmoke

EPA Burn Wise

EPA Choosing Wood Burning Appliances