# Irrigation Install



## Sfurunner13 (Feb 26, 2019)

I was reading through the irrigation tutorial and I camae across this paragraph under calculating GPM available.



My main line enter the hose and goes into my water meter. Piping is 3/4 copper. Directly after water meter it splits into my hose bib which is 1/2 copper (type L). From the split to the hose bib is 4 ft.



I was planning to tap into the main line further up and having to run 25 ft of piping to get it outside. I'm aware this is probably the better option. But my question is since My hose bib run is so short could I use the GPM of my 3/4 copper piping and install my backflow preventer directly after my hose bib outside.


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## g-man (Jun 15, 2017)

@Sfurunner13 i moved this to the irrigation folder.

A hose bib has a lot of pressure losses due to all the small orifices inside. If you want to go after the hose bib, then determine the gpm after the hose bib.


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## Sfurunner13 (Feb 26, 2019)

g-man said:


> @Sfurunner13 i moved this to the irrigation folder.
> 
> A hose bib has a lot of pressure losses due to all the small orifices inside. If you want to go after the hose bib, then determine the gpm after the hose bib.


3/4 copper piping should give me 11 gpm.

Just tested the hose bib gives me 11 gpm with static pressure of 50 psi.


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