How to Calculate BTU & Square Feet

BTU stands for British thermal unit and equals the quantity of energy necessary to increase the temperature of 1 pound of water by 1 degree Fahrenheit. Calculating BTUs is useful in determining the capacity of cooling and heating equipment. You can use BTUs and square foot measurement to choose the right size water heater or a heater for your swimming pool, for example, so you can enjoy warm water on cold days and nights.

Tape measure
BTU chart

Instructions

- 1
  Calculate the square feet of the area that is going to be heated. To obtain this information, use the tape measure to measure the length of the area, then measure the width and multiply them by each other. Note both measurements.
- 2
  Calculate the temperature increase you desire. First estimate the temperature you wish to achive. Then calculate the average daily temperature of your location, taking into account the temperature statistics of the coldest months. Subtract the latter from the former. The result gives the temperature increase you need from your heater.
- 3
  Compare the square feet and the temperature measurements with BTU charts available online. If you don't have a computer, you can easily gather the information from a store that sells the heater. These charts will help you find the BTUs required to heat a room based on the surface area and the increase in temperature.
- 4
  Find a heater that produces the output as specified by the chart. To know the output BTU of a heater, multiply the input BTUs of the heater with its efficiency rating. The efficiency rating of a heater or air conditioner is located on the side of the unit, usually on a plainly visible yellow sticker.

How to Inspect a Mobile Home for Leaks

How do I Fix a Dryer That Takes Two Cycles to Dry Clothes & Cuts Off During the Cycle?

Ventilation