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

Hello everyone,

I'm living in Montréal and I'm currently doing my first irrigation system for my new home. I started doing my homework of planning my system by looking at the available water source for the house. I have read many websites to try to get an idea of the best setup for my house, but I would like your advises.

Here's the specs:

Water is provided by the city and it enters directly in the basement from a copper pipe to the main shutoff valve (no water meter in my town), then it get transfered into a 3/4" Pex pipe to the rest of the house. There's a hose faucet outside the house on a 1/2 Pex pipe. I did the GPM test on it and got around 6-7GPM. I don't have a PSI gauge to plug on the faucet, but the house have a water softener on the main 3/4 Pex pipe and has 2 PSI gauge on it (One showing the around 60PSI from the main 3/4 Pipe and the other after the softener process going to the rest of the house is showing around 57PSI).

My first question, I find that the 6-7GPM out of the 1/2 faucet seems low. If I plan to connect my setup directly to the 3/4in main water Pex pipe before the water softener would this improve the GPM significantly?

I live where we have freezing winters (-22F/-30C) so I came to the conclusion that a Pressure vacuum breakers (PVB) wouldn't work outside unless I remove it for winter. I'm thinking instead to use a double check valve assembly (DCA) or a reduced pressure zone device (RZPD) if the pressure loss is acceptable, that would be installed in my heated basement (so it won't freeze). I would still drain the whole system every winter. Is that a good idea?

I read about the water velocity and that the best to avoid problems is to stay below the 5 feet per minute range. Would it be ok to connect a 1" pex pipe to the 3/4 main water pipe (after the main shutoff valve) using a Tee for my system? I'm wondering if the velocity inside the main 3/4 pex (before going into the 1" pex) would be an issue in that case or is this 5 fpm thing only applicable downstream of the system to protect the sprinklers/valves?

Do I need a pressure regulator on the system or is the sprinklers already able to regulate the pressure themselves?

Thanks for your time!