What is the weight in pounds of one gallon of water?

One gallon of water weighs approximately 8.33 pounds. This value is derived from the density of water, which is commonly accepted to be close to 8.34 pounds per gallon at standard room temperature. The often-used approximated figure of 8.33 pounds is more convenient for calculations in various applications, including plumbing and pipefitting, as it allows for straightforward conversions and estimations.

Knowing the weight of a gallon of water is crucial for pipefitters and those in related fields, as it assists in various tasks such as calculating pressure, determining the load on pipes and fittings, and ensuring systems operate properly under different conditions. It also aids in understanding how to manage water volumes effectively within a system, especially when designing for drainage and fluid transport.