BTU Calculator

1 How many cubic feet do you want to heat?

width

length

height

number of ft³

2 What is the temperature difference needed between the
outside temperature and the desired inside temperature?

outside temperature

temperature wanted
inside

difference in degrees

3 Déterminer le facteur pi³/BTU
Establish the BTU factor using the temperature difference in step 2:

Difference of

between the outside temperature
and the temperature wanted inside

Factor

4 What is the insulation or "R" factor?

Well insulated = Factor 2
Enclosed area with indows and walls installed.

Partly insulated = Factor 4
Walls installed, no insulation.
Doors and windows covered with tarps.

Poorly insulated = Factor 7
Mosts walls installed.

Not insulated = Factor 8,5
Main walls not installed, area enclosed by tarps.

5 Calculate the required BTUs:

number of ft³

BTU factor

"R" factor

Number of BTUs needed

Propane Consumption Guide

Here is a simple way of calculating your fuel needs when using a propane heater:

The basic rule:
At -17°C one 100 lb tank provides 64,000 BTU
At -7°C one 100 lb tank provides 94,000 BTU

Just divide your BTU needs by 64,000 or 94,000.

Example: A 300,000 BTU heater, temperature where the cylinders are located is -17°C
300,000 BTU/64,000 BTU = 4,69 cylinders

Since the law prohibits connecting more than 4 tanks of propane to a single piece of equipment, using 100 lbs tanks is not recommended to get maximum output.