Whole House or One Fixture? The Causes in Order
The PRV. Most La Vergne homes have a pressure reducing valve near the main shutoff, often by the water heater or where the line enters the house. It holds street pressure down to a safe level for your pipes. When a PRV ages, it can stick and starve the whole house. A gauge on an outdoor hose bib tells us in minutes whether pressure is low coming in or only low at fixtures.
A partly closed valve. After any plumbing work, a meter repair, or a winter shutoff, the main valve or a fixture valve may not have been fully reopened. It sounds simple, and it is one of the most common fixes we make.
Scale at one fixture. Rutherford County water is moderately hard, so mineral scale narrows aerators and showerheads over time. Unscrew the aerator, check for white grit, and run the faucet without it. Strong flow without the aerator means cleaning or replacing that small part solves it. Our faucet repair page covers fixture-level fixes.
Aging pipes. In older pockets of La Vergne, galvanized pipes corrode from the inside and slowly choke flow. Copper can develop pinhole leaks that bleed pressure. If pressure fell gradually over years and the house still has original galvanized lines, a repiping conversation may be more honest than another small repair.
A hidden leak. Pressure that drops suddenly, paired with a higher water bill, can mean water is escaping before it reaches your fixtures. See our guide to the signs of a hidden water leak and run the meter test described there.
Pressure Problems at a Glance
| Cause | Pattern you notice | What settles it |
|---|
| Failing PRV | Whole house weak, sometimes pressure surges then fades | Gauge test at a hose bib, static and flowing |
| Partly closed main or fixture valve | Sudden drop after other plumbing work | Valve position check along the supply path |
| Scaled aerator or showerhead | One fixture weak, others normal | Remove the aerator and compare flow |
| Corroded galvanized pipes | Slow decline over years, worse at upper floors | Pipe inspection and pressure test by section |
| Hidden supply leak | Sudden drop plus a bill increase | Meter test, then leak detection |
Homes in Heritage Valley built in the 1990s are now at the age where original PRVs fail, and slab homes in Lake Forest Estates sometimes show pressure loss from a supply leak under the slab. Both need a gauge and a test, not parts guessing.
