What kinds of math do plumbers need to know?
Math is a part of trade jobs, and the plumber's trade is no exception. In fact, basic math and several
forms of advanced math may be used by plumbers working out in the field or in the office.
A good plumber not only uses his hands, he uses his mind. In fact, he spends much of his time
troubleshooting problems with water pipes, plumbing fixtures and appliances. Many plumbers are
familiar with how to read a blueprint, and have even studied a little bit of chemistry and
bacteriology---but they also need to know math. Algebra and geometry are especially important
when it comes to layouts on the job, and basic math also comes in handy when a job calls for
The 45-Degree Formula
It is essential that every plumber knows how to connect two pieces of pipe. Math will play an
important role in getting this job done, so it is important for plumbers to understand a set of math
procedures known as the 45-degree formula. Plumbers-School.com explains that the 45-degree
formula takes the center measurement between the two pipes and multiplies it by the constant
1.414. The length of the two fittings is then subtracted from the original answer. However, there is a
stipulation. In order to accurately complete the measurement, the plumber must also know how to
convert a fraction to a decimal.
A plumber must know how to measure. Whether he will be measuring a length of pipe or measuring
for a fitting, it will be important to understand how to convert a decimal into a fraction. The
plumber's ruler utilizes inches and when doing conversions it will be necessary to take a
measurement such as 1 ½ inches and convert it to a decimal; which in this case would be 1.5 inches.
A plumber should also know how to measure the area of a water tank. According to Plumbing
Help.ca, some of the formulas used to measure area may include the area of a circle, which is
determined by the formula Area = diameter x diameter x .7854, as well as the surface area of a
sphere which is calculated by using the formula Area = diameter x diameter x 3.1416.
In the book "Plumber's Exam Preparation Guide,"
author Howard C. Massey explains that hydraulic
calculations are also important mathematical
procedures that are used by plumbers. Hydraulic
calculations include volume, which is measured in
cubic units and pressure; measured in pounds per
inch. Velocity is also a hydraulic measure, calculated
in distance and time.
Don't Forget the Charges
In order to get paid, a plumber must know how to
calculate his hourly rate times the amount of hours
that he worked. The Educations Resource Center
reports that this can be done by using a simple math equation which looks something like this:
$25/hr x 2 hours= $50 total labor cost.
Plumber's Exam Preparation Guide
The Educations Resource Center