Natural Gas. The fuel that heats our homes, our water, our ranges and dryers. Every house is different. Gas distribution is measure in BTUs, or British Thermal Units. A BTU is measured as the amount of energy needed to heat, or cool, 1 pound of water, by 1degree Fahrenheit.
For plumbers who install natural gas piping systems, the systems are sized by BTU load. As the BTU load increases, so will the pipe size. More volume of natural gas requires larger diameter piping.