Purpose:  The purpose of the Pipe Sizing Chart (above) is to help determine the size of a pipe.

Directions:  First, measure the circumference of the pipe by placing a flexible tape measure around the pipe.  (Note: If you don't have a flexible tape measure, simply cut a thin strip of paper or twine and wrap it around the pipe)  Second, measure the paper or twine and get the measurement.  Compare your measured circumference to the right hand column above.  The size of the pipe is on the left hand column.

Example:  You have a small pipe in your basement you want to insulate.  You wrap a piece of twine around the pipe and mark the circumference with a marker on the twine.  You then measure with a ruler the length of the twine which was wrapped around the pipe.  You measure just about 10 inches.  You then look at the chart and see the closest size is 9-3/4 inches which is a pipe size of 3-1/8.

CLICK HERE TO SEE THE OUTSIDE DIAMETER MEASUREMENTS FOR EACH PIPE SIZE

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