How to size greenhouse heater?

BTU or kW needed = (heat loss through structure) based on temperature difference, insulation, and wind.

Surface area, R-value of glazing, desired inside temp, outside low, ventilation losses.

Greenhouse Heater Size Estimator Calculator

Estimate the BTU output needed for a greenhouse heater based on its volume and the desired temperature difference.

Estimate the BTU output needed for a greenhouse heater to maintain desired temperatures.

Greenhouse Length (feet)

Greenhouse Width (feet)

Greenhouse Height (feet)

Desired Inside Temp (°F)

Lowest Outdoor Temp (°F)

The full supporting guide for this calculator is still being expanded. The tool remains accessible while we improve the educational content.

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