"My first choice for PEX was to use a
home run plumbing system with a manifold for my domestic water supply," Peterson says. "But REHAU offers an innovative fire suppression system that is integrated with the domestic water supply plumbing through a circulating pipe layout. Their design offers a cost-effective way to add fire protection to a home, but requires a different water supply layout from a homerun plumbing system."
"REHAU's fire suppression design is integrated with the domestic cold water supply, so all of my cold water fixtures are dropped from the loop in the ceiling that supplies the fire suppression sprinkler heads. Any time you use a faucet or flush the toilet, it circulates the water in the sprinkler lines, always keeping those lines fresh."
"I estimate that one would want to budget an additional $3,000 to $7,000 to the plumbing costs to include this type of fire suppression system to a residence. It did give me about a 15% reduction on my homeowner's insurance, though."
"My plumber ran my lines from the mechanical room up the walls and then through the attic space or the floor joist space. They ran all of the tube for the integrated fire suppression and cold water system in 3 or 4 hours (that was including installing the 50 fire suppression sprinkler tees). Depending on the brand of PEX product you choose, you can pressurize or test a line either as soon as the fittings are installed, or after a short 'reshaping' time as the PEX fully compresses into the fittings."
Most builders find that they can reduce their plumbing rough-in costs by switching from copper to PEX piping. Although material costs are about the same, the savings come from labor due to significantly reduced installation time.
"I found material costs to be roughly equivalent to copper," Peterson says. "Depending on the manufacturer, the fittings are substantially more expensive than copper fittings, but a PEX system requires only 10 to 20% the number of fittings as traditional plumbing systems. And there is an obvious savings on installation costs with PEX because of how fast it goes in."
"Each manufacturer has its own patented fitting system, requiring an investment in that manufacturer's installation tools. However, many plumbing supply houses will rent the tools out to plumbers. Also, the technology uses no acetylene, solder, or glues, contributing to safer working conditions."