How do I increase water pressure in house?

Low water pressure that drops to a trickle when multiple fixtures run typically points to a restriction, a failing pressure regulator, or supply limitations under the Ontario Building Code (OBC). ​To diagnose and resolve this issue: ​Check the Main Shut-off & PRV: Ensure your main water supply valve is fully open. If your home has a Pressure Reducing Valve (PRV)—common in municipal supply setups across Ontario—a failing PRV often restricts flow and causes pressure drops. ​Inspect for Scaling or Clogs: Mineral buildup (calcium/lime scale) in older galvanized supply pipes or clogged aerators on individual fixtures can severely restrict volumetric flow. ​Verify Meter & Service Size: If your home has undergone additions or increased demand, an undersized municipal service line or water meter may struggle to handle simultaneous loads. ​A licensed plumber can perform a static and dynamic pressure test to pinpoint the restriction and ensure your plumbing layout complies with Ontario standards.

Low water pressure throughout the house, especially when the pressure drops significantly after opening a second tap, usually indicates an issue with the main water supply rather than an individual faucet. Common causes include a partially closed main shut-off valve, a faulty or incorrectly adjusted pressure-reducing valve (PRV), clogged or corroded supply pipes, or low incoming water pressure. The first step is to test the water pressure at the main supply and check the main shut-off valve and PRV. Once the actual pressure is measured, it will be much easier to determine whether an adjustment, valve replacement, pipe repair, or another solution is required.