cost to replace PEX
1 Re-plumbing a house (installing new lines and abandoning the old ones) with PEX can cost $1,500-$8,000 or more. 2  Re-plumbing costs are typically based on the number of fixtures, with each sink, bathtub, shower, toilet, dishwasher, water heater, etc. counting as one fixture. Specialized tools are required to cut PEX tubing, install connections and check the tightness of crimped connections. 2  These can cost $50-$200 each, depending on size and type; a basic PEX tool kit typically costs about $90-$150. 3  Get several estimates.