Stove Builder International 2.5R Series (Solution 2.5 ZC II
Stove Builder International 2.5R Series (Solution 2.5 ZC II is a non-catalytic wood stove from Stove Builder International certified at 1.2 g/hr particulate emissions with 64% HHV efficiency and a 12,700–60,700 BTU/h output range.
| Appliance type | wood-stove |
|---|---|
| Combustion technology | Non-Catalytic Stove |
| Certified fuel | Cord Wood |
| Covered model numbers | 2.5R Series (Solution 2.5 ZC II, Stratford II, FP10 Lafayette II, FP12 Mundo II, HE250R, Destination 2.7, Matrix 2700, FP10 Lafayette IIS, WFP-75 8411, HE275, HE275CF, Green Mountain Insert 90 8460, St. Clair 2500) |
| Emission rate | 1.2 g/hr |
|---|---|
| Carbon monoxide | 1.6 g/min |
| Efficiency (HHV) | 64 % |
|---|
| Heat output (low) | 12700 BTU/h |
|---|---|
| Heat output (high) | 60700 BTU/h |
| Firebox volume | 1.94 cu ft |
| 25C tax credit eligible (≥75% HHV) | No |
|---|---|
| 2020 NSPS compliant | Yes |
| Currently in production | Yes |
| EPA certification number | 321-22 |
What space does the Stove Builder International 2.5R Series (Solution 2.5 ZC II suit?
- Its 60,700 BTU/h peak output covers roughly 1,750–2,450 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 1.94 cu ft firebox puts it in the mid-size home class.
- Rough fuel use: about 3.1 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
- Foyers Supreme Astra Duo 38 (2.2 g/hr)
- United States Stove Company US2500E (0.88 g/hr)
- Pacific Energy Fireplace Products Limited NEO 2.5 LE (2 g/hr)
- Travis Industries Answer (2 g/hr)
- New Buck Corporation (Buck Stove Corp.) Model 81 (1.1 g/hr)
- Jotul North America (Jotul U.S.A., Inc.) F35 (1.2 g/hr)
Frequently asked questions
Is the Stove Builder International 2.5R Series (Solution 2.5 ZC II EPA certified?
Yes, the Stove Builder International 2.5R Series (Solution 2.5 ZC II is on the EPA's current list of certified wood heaters (certification number 321-22) and meets the 2020 NSPS Step 2 emission limits.
What is the Stove Builder International 2.5R Series (Solution 2.5 ZC II's emission rate?
The Stove Builder International 2.5R Series (Solution 2.5 ZC II is certified at 1.2 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 2.5R Series (Solution 2.5 ZC II heat?
Roughly 1,750–2,450 sq ft, estimated from its 60,700 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 2.5R Series (Solution 2.5 ZC II 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 2.5R Series (Solution 2.5 ZC II'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)