I'm wondering if I can switch from a 1/2" main water supply to a 3/4" water supply anytime? Let me explain, I have 3/4" main from the water meter but when this (old house) was built, the 3/4" switches to 1/2" under a cement patio. It currently runs 1/2" throughout. My wife and I are adding to a master bedroom suite with a new bathtub, two head shower, 2 sinks, and an additional toilet. From everything I've read, 3/4" increases the volume of water so additional fixtures can be accommodated. I want to switch back to a 3/4" copper pipe only a few feet from where it converts to 1/2" in the first place. So, it will go 3/4" from the meter (under the cement), 1/2" for about 10 feet, then switch back to 3/4" for a main through out the house. Does this sound like the best approach?