Yesterday John Podelak, our plumber came over to lay out his sewer lines in the foundation. The sewer pipes have to go in prior to pouring concrete. Sewer lines are 4” PVC pipes.
Normally water lines today are made of PEX (polyethylene) material, and are also run through the slab. However, we are using copper lines and running them through the walls. Some folks might not agree, but here are the reasons for these choices:
Water Lines in Walls
--- This gives better access to the lines if a leak issue should develop.
--- It is easier to insulate the hot water lines in the walls than in the slab.
Copper Lines instead of PEX
--- Copper is more expensive than PEX tubing. However, PEX should be sleeved when installed in a slab, which increases cost.
--- PEX will be damaged by sunlight, so there concerns about how they have been handled prior to installation.
--- There are questions about the effect of chlorinated water on the PEX.
--- PEX is made from petroleum products. There has been some controversy about whether chemicals will leach into the water. However, PEX is approved in all states. (California was last to approve in 2009). Jim is personally averse to plastic water bottles, etc., so this is not a good fit for us.