Low Water Pressure: Causes, Fixes, and What It Costs
From clogged aerators to failed pressure regulators — diagnose before you call.
Low water pressure has dozens of causes ranging from a $5 aerator clog to a $4,000 service line replacement. Diagnosing in the right order prevents wasted plumber visits and unnecessary work.
Diagnose before you call
Is the problem at one fixture or all fixtures? Single fixture: usually a clogged aerator (unscrew and clean — $0) or supply valve. All fixtures: house-wide issue.
Is it hot side only, cold side only, or both? Hot only: water heater issue (sediment buildup or failing dip tube). Both: main supply problem.
Common causes and costs
Failed pressure regulator: $250-$500 to replace. Common cause of house-wide pressure problems in homes 10+ years old.
Partially closed main shutoff: free fix if found.
Galvanized supply lines corroded internally: $4,500-$10,000 whole-home repipe. Almost universal in homes with original galvanized still in place.
Main service line leak or restriction: $2,500-$6,000 for replacement.