What Causes Low Water Pressure in a Home?

The first question with low pressure is how much of the house is affected, because that immediately narrows the cause.

One fixture only

A blocked aerator, a partly closed shut-off, or a worn cartridge inside the tap. These are usually the quickest to resolve.

Hot water only

Points toward the water heater, its shut-off valve, or sediment in the hot side rather than the incoming supply.

The whole property

A main shut-off not fully open, a pressure-reducing valve issue, corrosion and scale narrowing older supply pipework, or a leak somewhere on the supply line drawing off flow before it reaches the fixtures.

Pressure loss with a damp smell

Reduced pressure alongside moisture, staining or rising water use is worth investigating as a possible leak rather than treating as a pressure problem on its own.