What certification actually is
EPA's New Source Performance Standards for residential wood heaters set a maximum particulate emission rate that a model must meet before it can be sold. A certified model has been tested by an accredited lab against that standard and appears in EPA's public database. Certification is about the appliance, not about your house, your chimney, or your installer.
Certification does three practical things for a buyer:
- Many local change-out and rebate programs require it, and some require that your old stove is not on the list.
- Some insurers ask for it.
- Some jurisdictions restrict the sale or installation of uncertified appliances.
What certification does not do: it does not tell you the stove is well built, it does not tell you it will heat your square footage, and it does not certify your installation.
The numbers on a certification, one at a time
Emission rate, grams per hour
The headline number. It is particulate matter released per hour under a standardized test protocol.
| Wood stoves | Pellet stoves | |
|---|---|---|
| Models in database | 1,155 | 283 |
| Median emission rate | 3.1 g/hr | 1.3 g/hr |
| Range | 0.3 to 7.5 g/hr | 0.08 to 6.6 g/hr |
Pellet stoves run cleaner as a class because the fuel is dimensionally uniform and the feed rate is metered. This is a fuel and mechanism difference, not a brand quality difference.
Real examples at the clean end, all figures read from their EPA listings: the Vermont Castings Intrepid FlexBurn 2115-CAT, certified by Hearth and Home Technologies, at 0.3 g/hr; Travis Industries' Cape Cod at 0.45 g/hr; Woodstock Soapstone's Progress Hybrid 209b at 0.46 g/hr; and Jotul's F 500 V3 at 0.5 g/hr.
Note what the first of those already demonstrates: the certificate says Hearth and Home Technologies while the stove says Vermont Castings, and the non-catalytic 2115 variant is a separate listing at 0.6 g/hr. The exact variant matters.
Heat output, BTU per hour
EPA publishes a range, not a single number, because output varies with burn rate. The Woodstock Soapstone Ideal Steel Hybrid 210 lists 12,300 to 57,000 BTU/hr. Kuma's Sequoia (K100/300/400) lists 10,100 to 52,100 BTU/hr.
Read the low end as carefully as the high end. A stove whose floor is 12,000 BTU/hr will overheat a small, tight room in shoulder season. Oversizing is the most common sizing mistake and it shows up as a stove you damp down until it smolders, which raises emissions and creosote both.
Efficiency, percent HHV
HHV is higher heating value. It is the share of the fuel's total energy that ends up as heat in your room rather than up the flue.
Of the 1,438 models, 532 publish an efficiency figure. Among those:
| Models publishing efficiency | Median | Range | |
|---|---|---|---|
| Wood stoves | 354 of 1,155 | 73% | 59 to 84% |
| Pellet stoves | 178 of 283 | 76% | 51 to 87% |
The highest published wood stove figure in the database is the Kuma Stove and Iron Works K100/300/400 Sequoia at 84%. Blaze King's 30.2 series (Sirocco 30.2, Ashford, and siblings) publishes 83% at 0.81 g/hr. Woodstock Soapstone's Ideal Steel Hybrid 210 publishes 82% at 1.0 g/hr.
On the pellet side, Extraflame's V5.2 publishes 87% at 0.59 g/hr, the highest figure in the pellet set. SMG Hearth and Home's HP42-Alpine publishes 86%, and Enerco's PS20W model line publishes 85%.
Catalytic, non-catalytic, or hybrid
EPA records the combustion technology. The three classes perform differently in the database and the difference is large enough to matter when you shop.
| Class | Models | Median efficiency (of those publishing) | Median emission rate |
|---|---|---|---|
| Non-catalytic | 1,082 | 72% (409 models) | 2.9 g/hr |
| Catalytic | 315 | 78% (81 models) | 2.4 g/hr |
| Hybrid | 39 | 78% (38 models) | 1.0 g/hr |
Catalytic and hybrid stoves post better numbers. They also carry a consumable: the combustor degrades and gets replaced on a schedule, typically after several seasons of use, at a real parts cost. Ask the dealer for the replacement part number and price before you buy, and treat the answer as part of the purchase price.
NSPS 2020 compliance
The database flags whether a model meets the 2020 step of the standards. 409 of the 1,438 models carry a Yes; 1,029 carry a No. A No is usually an older certification still listed in the database rather than a currently manufactured appliance. If a program you are applying to requires 2020 compliance, that flag is the one to check, and it is not the same field as efficiency.
How to use this when you shop
Ask for the model line, exactly. EPA certifies model families, so one certificate often covers several names. The Enerco PS20W listing covers PS20W, PS20WTS, and C30XL among others. If the showroom tag says one name and the certificate says another, that is normal, and the certificate is what a rebate program will want.
Watch for near-identical listings with different numbers. The same model family often appears more than once in the database under separate certifications, and the figures differ between them. Blaze King's Ashford, Chinook, and Sirocco 30-series appears across several listings ranging from 75% to 83% efficiency and 0.8 to 0.97 g/hr. Enerco's PS20W line appears twice, at 85% and at 76%. These are different certifications, not errors, and a rebate program will want the specific certificate covering the appliance you bought. Match the certificate number, not the family name.
If you are chasing a 75% threshold, verify the published figure before you sign. 236 models clear it. Many models in a showroom do not publish a number at all, and no dealer can make one appear.
Do not shop on efficiency alone. A 73% stove that is correctly sized for your room and burned on dry wood will outperform an 82% stove you have to choke down. Fuel moisture swamps a few points of rated efficiency.
Check the old stove too. Several change-out programs, including Washington's Columbia Basin grant, pay specifically for surrendering a stove that is not in this database.
What this page does not tell you
Manufacturer names in EPA's database are certifying legal entities, not the brand on the casting. Hearth and Home Technologies certifies models sold as Heat & Glo, Quadra-Fire, and Vermont Castings among others. We join models to consumer-facing brands where we can and publish the join basis. 191 distinct certifying manufacturer names appear across the 1,438 models. Those are the certifying entities, which is a different field from the brand a stove is sold under, and the two counts should never be read as the same number.
EPA does not publish terms of use on the certified heater pages we read, and our reading of 17 U.S.C. §105 (federal works) is our own reading and not legal advice.
Methodology and freshness
Source: EPA's certified wood heater database, full ingest 2026-08-15, 1,438 models. Every figure on this page is computed from that ingest and none is estimated. Blank fields are reported as blank. Efficiency medians and ranges are computed only over models that publish an efficiency figure and never imputed for those that do not. Refresh cadence: quarterly.
Corrections: if a model's listing here disagrees with its certificate, tell us and we will correct or remove it.
This page is a reference directory, not certification, legal, or installation advice. We do not sell, install, or service stoves and we do not arrange installation work.