I'm going to repost a few pics from the Awesome Irrigation thread, to jumpstart a new idea. Post pictures of your tap and backflow installation, since everyone does different things. I'm curious to see how other people do DC's, as well as seeing some PVB and RP installs. Maybe Boots might show off his barometic loop. Anyways: Domestic line was 1 1/4" NSF 200 PSI Poly pipe, I use brass insert fittings and a union to install a tee, the white wire next to the poly is the 220v line for the well pump. Here I used a 1" nipple to bring it up to a decent height ( I don't like Doublechecks 18" down) and a Street El, before a 1" Brass FORD ball valve. Best ball valves on the market. I don't have a picture of the doublecheck, but I used a close nipple and threaded it right on after the Ford valve. This is how 95% of my taps are done. We only use brass before the backflow, and when we run domestic lines we only run NSF 200 PSI poly.