What is the grams-per-hour emissions limit for new wood stoves?
The limit is 2.0 grams of smoke particulate per hour for a new wood stove on the crib-wood test, or 2.5 grams per hour on the cordwood test method — the EPA's Step 2 standard, in force since May 15, 2020. For perspective, old uncertified stoves from the '70s and '80s often put out 15 to 30-plus grams an hour.
Two numbers, two test methods
You'll see the limit quoted two ways because the EPA allows two test fuels. Crib wood — dimensioned lumber stacked to a spec — carries the 2.0 g/h cap. The cordwood method, which uses real split logs closer to what you'd actually burn, allows 2.5 g/h. Many manufacturers now certify on cordwood because it reflects real-world use. Either way, the number on the tag is the ceiling; plenty of good stoves certify well under it.
Grams per hour is smoke, not heat
It's worth being clear about what the figure measures: particulate matter — smoke — leaving the stove, in grams each hour. It is not a measure of how much heat you get. In fact the two pull in opposite directions in a good design: a stove that burns its smoke instead of venting it keeps more of that energy in the room as heat, and dumps less creosote in your chimney. Lower g/h generally tracks with a cleaner, safer, more efficient burn.
Reading it on the appliance
The grams-per-hour number lives on the EPA hangtag and the permanent certification label, right next to the efficiency rating. A stove without those figures is uncertified, and we won't install it. When we help you choose — say a Regency Cascades F1500 — we'll walk you through the emissions and efficiency numbers so you know what you're getting before anything's ordered. Call (828) 545-0525 to talk it through.
Related questions
- What are the current EPA emissions rules for wood stoves?
- What does EPA 2020 certified mean on a wood stove?
- How much cleaner is a new EPA-certified wood stove than an old one?
- Do catalytic wood stoves burn cleaner than non-catalytic ones?
- Does an EPA-certified wood stove use less firewood?
- Do gas fireplaces affect indoor air quality?
Still deciding? Talk to a real installer.
Free assessments across Western North Carolina — no pressure, straight answers.