Heating Basics
Contents
1. Heat loss & ΔT
Heating demand rises with the temperature difference (ΔT) between inside and outside, and with the quality of the building envelope and air infiltration. A simple rule: losses ≈ H·ΔT + 0.33·ACH·V·ΔT (H in W/K, ACH = air changes per hour, V = volume).
2. Insulation & windows
- Roof/attic insulation has the highest impact per dollar.
- Seal thermal bridges (continuous metal parts).
- Use double glazing and thermal curtains to cut losses.
3. Off-grid heating systems
- Wood stoves: robust, local fuel, modern EPA-certified units are cleaner.
- Pellet stoves: efficient but need electricity for auger/fan.
- Propane: easy to control, requires ventilation and CO detector.
- Heat pumps: highly efficient if powered by a strong solar system.
- Thermal mass: adobe or brick walls help smooth temperature swings.
4. Fuels & efficiency
- Dry wood: ~3.8–4.3 kWh/kg.
- Propane: ~13.6 kWh/kg.
- Typical efficiencies: wood 60–80%, propane 80–95%, heat pumps COP 2.5–4+.
5. Quick sizing
Use the Heating Needs Calculator for detailed results. As a shortcut: well-insulated small cabins need 30–60 W/m² in temperate cold climates, poorly insulated ones can exceed 80–120 W/m².
6. Safety
- Always install CO/smoke detectors.
- Ensure proper ventilation for propane or wood stoves.
- Clean chimneys and flues regularly to avoid creosote buildup.