What pipe sizing means
Pipe sizing is choosing supply pipe diameters so every fixture gets enough flow and pressure at the same time, based on fixture units, pipe length and the starting pressure.
Where it matters on a plumbing job
Undersized supply lines show up as a shower that goes cold or weak when a toilet flushes. On repipes and additions, size the lines on paper first and put the sizes in the estimate.
What it costs
Jobs that involve pipe sizing are priced in the main water line replacement cost guide: about $1,700 typical, usually $1,200 to $10,000. The guide shows its sources and what moves the price. The water pipe sizing calculator prices a job line by line.
Work it out
- Free calculator: Water pipe sizing calculator
- Cost guide: Main water line replacement cost
- Licensing: Plumbing license rules by state
- Tools, templates and guides: Free plumbing resources