I am needing to install a PBV Backflow for my sprinkler system. I will be tieing into the main water line from inside my basement and going out under the foundation. The house was built in 1915 and basically only has about an 8" thick footing, which is maybe 1-1/2' below grade, at the point where I plan to tie into.
The main supply to the house is 3/4" copper, but I have an area, where I tee'd off the main line with 3/4" pex so I could place all outside hydrants on a shut off valve inside the house.
I have 2 questions:
1) Should I tee off the pex for the irrigation system or off of the main copper line? If I tee off the pex, I would have 1 more shut-off location if anything went wrong....but I question if I'd have more pressure if I tee off the copper, since less bends and such. I have easy access to both lines in the same area.
2) What is the best option for material to use for the supply side of the PBV Valve? PVC seems to be the most commonly used, but I am not real sure I want pressurized PVC inside my basement running underneath the footing. I will likely sleeve whatever I go with.