PEX plumbing system designs can save water and energy because of the elimination of the pipes between the water heater and the faucet. There are three proven design PEX options that are showed in the layouts bellow.

Tank-and-branch systems – consist a large trunk lines for water distribution trough the house. They have large numbers of fittings that makes this system cost more, slower for installation and more leaking possibilities.
Home-run manifold systems don’t rely on large pipe for water distribution so this way you can safe water and energy at once. Actually you don’t need to wait long before the water become hot in this case. But, it uses a lot of PEX and there are a lot of holes. Submanifold Systems – requires less pipes and drilling, but don’t save the water. For that you need to add a main mainfold and recirculating pump. More, in the link bellow.

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