Burn Days, No-Burn Days, and What They Mean for Your Fireplace

How the rules work in practice

They are not advisory and they are not the same in both districts, so it is worth knowing which applies to you.

The Bay Area

Spare the Air alerts are issued when particulate is forecast to be high, typically on still cold nights between November and February. On an alert day, burning wood is prohibited. Status is published daily and there are notification services.

The San Joaquin Valley

A tiered curtailment system through the winter season, with levels that restrict or prohibit wood burning depending on the forecast. The valley has some of the worst winter particulate in the country, which is why the rules are stricter.

Exemptions exist

Both districts have provisions for households where wood is the sole source of heat, and for areas without natural gas service. Those are registered exemptions rather than assumptions — if you think you qualify, check with the district rather than relying on it.

Gas is generally not restricted

Which is the practical reason so many households have moved to gas inserts and log sets.

What it changes about maintenance

Less burning does not mean less maintenance. It changes what the maintenance is for.

Creosote builds more slowly, other things do not

A fireplace used a handful of times a winter accumulates little creosote. It still collects nesting, its damper still seizes, its cap still corrodes and its arrestor still blocks. The annual inspection is the part that matters; the brush is close to incidental.

An appliance nobody uses is an appliance nobody checks

This is the real risk in restricted areas. Faults develop over years without anyone noticing because nothing prompts attention. Then someone lights it on the one cold evening it is permitted.

If you switch to a gas insert

It needs a liner sized to the appliance. Venting an insert into an open masonry flue is a fault — the gases cool, slow and condense, and the appliance will not draft as designed. Most manufacturers require the liner.

Burning better on the days you can

If you do burn wood, doing it well matters more where the rules are tight, because the rules exist because of what poor burning produces.

Seasoned hardwood below about twenty percent moisture burns hot and clean. Unseasoned wood spends the fire's energy boiling water out of itself, runs cool and smoky, and produces both the particulate the districts are measuring and the creosote that coats your flue. A moisture meter costs very little and settles the question.

The other habit is not damping the fire right down. Cool smoke condenses and pollutes; hot smoke leaves.