Why Your Water Pressure Dropped
Where the pressure drops tells you most of what you need to know.
Call for Plumbing HelpOne fixture only
Start with the aerator on the faucet or the shower head. Mineral scale builds up quickly on hard water and is a five-minute fix. If cleaning it does nothing, the fixture's cartridge or the stop valve under it is the next suspect.
Hot water only
Weak pressure on the hot side alone often points at sediment in the water heater or a partially closed valve on its outlet.
The whole house
A pressure-reducing valve that has failed, a partly closed main shutoff, a leak in the water line, or corrosion inside older galvanized pipe can all drop pressure everywhere. A gauge on a hose bib gives a real number to work from rather than a guess.