Stove Builder International HE350
Stove Builder International HE350 is a non-catalytic wood stove from Stove Builder International certified at 1.6 g/hr particulate emissions with 64% HHV efficiency and a 16,600–43,000 BTU/h output range.
| Appliance type | wood-stove |
|---|---|
| Combustion technology | Non-Catalytic Stove |
| Certified fuel | Cord Wood |
| Covered model numbers | HE350, FP-15-Waterloo, Horizon, Monaco XL, WFP100, FP-15A Waterloo, St. Clair 4300, Solution 4.5 ZC |
| Emission rate | 1.6 g/hr |
|---|---|
| Carbon monoxide | 2.6 g/min |
| Efficiency (HHV) | 64 % |
|---|
| Heat output (low) | 16600 BTU/h |
|---|---|
| Heat output (high) | 43000 BTU/h |
| Firebox volume | 4.28 cu ft |
| 25C tax credit eligible (≥75% HHV) | No |
|---|---|
| 2020 NSPS compliant | Yes |
| Currently in production | Yes |
| EPA certification number | 64-16 |
What space does the Stove Builder International HE350 suit?
- Its 43,000 BTU/h peak output covers roughly 1,250–1,700 sq ft at the 25–35 BTU/h-per-square-foot rule of thumb — see the sizing calculator to adjust for your insulation and climate.
- The 4.28 cu ft firebox puts it in the large-home, overnight-burn class.
- Rough fuel use: about 2.5 cords per season at the midpoint of its output range (8 burn-hours/day, 150-day season, 22 MMBtu/cord — see methodology).
- Certified burning Cord Wood — the test fuel closest to real-world firewood.
Similar wood stoves
- Hearthstone Quality Home Heating Products WFP100 (1.6 g/hr)
- FPI/Regency Fireplace Products I2500 (1 g/hr)
- New Buck Corporation (Buck Stove Corp.) Model 91 (1.3 g/hr)
- Woodstock Soapstone Company 210a Ideal Steel Hybrid (0.89 g/hr)
- Travis Industries Rockport NexGen-Hybrid (0.73 g/hr)
- Morso Jernstoberi A/S 5660 B (1.2 g/hr)
Frequently asked questions
Is the Stove Builder International HE350 EPA certified?
Yes, the Stove Builder International HE350 is on the EPA's current list of certified wood heaters (certification number 64-16) and meets the 2020 NSPS Step 2 emission limits.
What is the Stove Builder International HE350's emission rate?
The Stove Builder International HE350 is certified at 1.6 grams of particulates per hour (tested with cord wood). Real-world emissions depend heavily on fuel moisture and operation — the lab figure assumes seasoned fuel and correct air settings.
How many square feet can the Stove Builder International HE350 heat?
Roughly 1,250–1,700 sq ft, estimated from its 43,000 BTU/h peak output at 25–35 BTU/h per square foot. Insulation, climate, ceiling height, and floor plan move this figure substantially in both directions.
Does the Stove Builder International HE350 qualify for a federal tax credit?
No — the federal 25C credit for biomass stoves was terminated for property placed in service after December 31, 2025. The Stove Builder International HE350's certified efficiency is 64% HHV, which did not meet the credit's ≥75% HHV threshold while it existed. State and local incentive programs may still apply — check your state energy office and air district.
Sources
- cfpub.epa.gov (retrieved 2026-07-23)