Pipe Diameter Change
Name: Dan B.
Date: June 2004
What are the advantages of increasing the diameter of
3/4" diameter water pipe to 1" diameter water pipe? Typically, the main
water supply comes in on a 3/4" diameter pipe. Plumbers seem to tee off
the 3/4" diameter pipe and increase the size of the pipe to 1" diameter
for irrigation systems. What is the reasoning behind this? Does the
volume, pressure, and or flow rate change to benefit irrigation systems?
This sounds like a plumbing and building code problem. A large pipe will
flow more water than a smaller. I assume that builders and water supply
people have decided that 3/4" is adequate for most uses. For irrigation,
which involves long distances, it is wise to go up to 1" to minimize any
further loss in flow. Of couse, 1" throughout would be better than a mix of
3/4" and 1".
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Update: June 2012