Water pressure & elevation
Enter the pressure at the meter and the fixture height to see what pressure arrives, and when code requires a regulator.
Typical city supply: 40–80 psi. Measure with a hose-bib gauge.
Second-floor shower head ≈ 18–20 ft in a typical house.
Most fixtures: 8 psi minimum. Flush valves: 15–25 — check the spec sheet.
Result
Clears the fixture's 8 psi with 44.2 psi to spare (before friction losses in the pipe).
How is this calculated?
Using the tool
Water is heavy, and the building makes it climb: every foot up costs 0.433 psi, every foot down gives it back. Put in the static pressure at the meter and where the fixture sits — you get what actually arrives, whether it clears what the fixture needs, and the code flag when the street pressure is high enough to require a regulator.
The physics
A column of water one foot tall pushes down with 0.433 psi(62.4 lb per cubic foot spread over 144 square inches) — that's the whole tool. Pressure at the fixture = static pressure − 0.433 × feet of climb, and a basement fixture gainsthe same way. It's also why a 100 ft water tower makes about 43 psi at the ground with no pump running. This is the static picture: open the tap and friction in the pipe and fittings takes another bite, which is a pipe-sizing question — the next tool in this area.
New to the math? Learn the concept: Plumbing fundamentals