Double Check Valve installation (and a few other questions)
I want to put my own underground sprinkler system in my yard this summer. I planned to call a plumber to branch off my water supply line just after the meter, install all the valves, and leave a stub for me outside so I can connect the sprinkler manifold. I called the plumber yesterday, and he told me that would cost around $900, which was about 400-500 more than I thought/hoped it would be.
So, I'd like to try to do this myself. Ideally, I think I want the following components right after the tee branch (right?):
Tee...stop valve...double check valve...stop valve...boiler valve...out through the wall.
1) Is it easy to install a double-check valve? Is it just as simple as installing a normal valve? They are expensive, so I'd obviously want to be certain I would not break it.
2) I planned to use a Watts 007 Double Check valve assembly, is that a good choice?
3) Should I install a strainer before the double-check valve, like watts website says? I have seen arguments for and against it.
4) Where should I make the conversion to PVC for the sprinkler system, inside or outside?
5) When I drill out through my foundation, should I drill above ground, or dig outside and drill underground so the pipe can go horizontally into the valve box?