SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

In an irrigation system... bigger pipes are better because it means less pressure losses due to friction between the water and the pipe wall.

The only negatives to larger pipes is that generally, larger means more money, and of course you would lose more water if the pipes drain between each use.

And mixing and matching doesn't hurt anything provided your system is designed to handle the smallest pipe.



As a general comment, from what I've read, you generally don't want to use 1/2" pipe in an irrigation system unless it's for feeding drip irrigation or its the last few feet of pipe suppying water to a single spray. The general reasons include typically huge pressure losses and higher likelyhood of water hammer (because the smaller the pipe, the faster it has to go).