Low water pressure in London Ontario is one of those problems that starts as an annoyance and slowly drives you crazy. A weak shower. A tap that barely trickles. A dishwasher that takes forever to fill. Before you call a plumber there are a few things worth understanding — because the cause of low pressure changes everything about the fix.
I’m Aron Oretan — a Licensed Red Seal Plumber and Steamfitter with 26 years in the trade. Here’s how I diagnose low water pressure in London Ontario and what can actually be done about it.
The First Question I Ask Every Homeowner
When someone calls about low water pressure the first thing I ask is simple. Where are you experiencing it? Is it happening throughout the whole house? Or is it just one fixture — one shower, one sink, one tap?
That single answer points me in two completely different directions. Furthermore it often tells me whether the homeowner can fix it themselves or whether we need to come out.
Low Pressure at Just One Fixture — Often a DIY Fix
If the pressure problem is isolated to one fixture the cause is almost always something local to that fixture. Here are the three most common culprits.
Blocked aerator. The aerator is the small screen at the tip of your faucet. Over time sediment and mineral deposits collect in that screen and restrict water flow. As a result what feels like low pressure is actually just a blocked aerator. Unscrewing it, rinsing it out, and screwing it back on takes five minutes. This is something most homeowners can do themselves.
Calcium buildup on the showerhead. London Ontario has hard water. Mineral deposits accumulate inside showerheads over time and block the spray holes. Soaking the showerhead in white vinegar overnight dissolves the calcium and restores full flow. Again this is a DIY fix.
Something stuck in the valve cartridge. If cleaning the aerator and showerhead doesn’t help the problem may be inside the valve or faucet cartridge itself. Debris or sediment can get lodged in the cartridge and restrict flow. In that case the cartridge needs to be removed and cleaned or replaced. This one is more involved and worth calling a plumber for if you’re not comfortable with it.
Whole House Low Pressure — What’s Actually Going On
If the pressure is low throughout your entire home the conversation gets more interesting. Because here’s something most homeowners don’t know.
Water pressure is geography — not a knob you can turn.
Your home’s water pressure is a function of its location relative to the City of London’s reservoir or pumping station. The further your home is from the pumping station — or the higher your home sits relative to it — the lower your pressure will naturally be. If your house is at the top of a hill and the pumping station is at the bottom, your pressure will be lower than your neighbour’s house at the bottom of that same hill. That’s physics. It’s not a plumbing problem.
So when a homeowner calls about whole house low pressure the first thing we do is test the pressure after the water meter. We’re looking at the actual PSI coming into the home. If it’s under 40 to 45 PSI and the homeowner is genuinely bothered by it, a booster pump is the solution. A booster pump increases the pressure of water entering the home and maintains consistent pressure throughout. It’s an effective fix for homes with chronically low municipal pressure.
Low Pressure Caused by Your Plumbing — What to Check First
Before assuming the problem is municipal pressure it’s worth checking a few things inside the house. Sometimes the cause is much simpler.
A partially closed valve. I’ll be honest — I’ve done this myself. After a plumbing repair I’ve slowly opened a valve, checked everything was working, and then forgotten to open it fully before leaving. A partially closed valve restricts flow and feels exactly like low pressure. Check the main shutoff valve where the water enters your home. Make sure it’s fully open. Check any other shutoff valves under sinks or near fixtures that may have been turned during a repair. This is something homeowners can often fix themselves.
Galvanized pipe. Older London Ontario homes — particularly in Old South, Wortley Village, and Old East Village — often still have galvanized steel water lines. Galvanized pipe rusts from the inside out. Over decades that rust narrows the inside diameter of the pipe and restricts flow. As a result pressure and volume both drop. If galvanized pipe is the cause replacement is the fix. There’s no other solution.
Pressure vs Volume — A Distinction That Matters
This is something most homeowners — and honestly most plumbers — don’t explain clearly enough.
Pressure is the force of water coming out of a tap. Volume is how much water can flow at one time.
These are different problems with different causes. If you have a half-inch water main into your home and multiple people are using water simultaneously — showers running, dishwasher going, laundry machine filling — you’ll feel like you have low pressure. However what you actually have is insufficient volume. The pipe simply can’t deliver enough water fast enough to satisfy simultaneous demand.
Upsizing the water main from half-inch to one-inch — which the City of London now requires on all new installations — dramatically increases the volume of water available to your home. Similarly upsizing the distribution pipes inside the house addresses volume restrictions on specific branches.
Understanding whether you have a pressure problem or a volume problem changes the recommended fix completely. That’s why the diagnostic conversation matters before anyone recommends a solution.
Learn more about Triton’s plumbing services in London Ontario
How Hard Water Affects Water Pressure in London Ontario
London Ontario’s hard water accelerates the pressure problems I’ve described above. Mineral scale builds up inside galvanized pipes faster in hard water areas. Aerators and showerheads clog more frequently. Furthermore scale can build up inside valves and cartridges over time reducing flow.
A water softener reduces mineral buildup throughout your entire plumbing system. As a result your fixtures, valves, and pipes stay cleaner longer and pressure-related problems become less frequent. If you’re on well water in Oxford County or Elgin County where hardness can reach 41 grains per gallon, a water softener isn’t optional — it’s basic home maintenance.
Frequently Asked Questions About Low Water Pressure in London Ontario
Why is my water pressure low in London Ontario? There are several possible causes. For a single fixture the issue is usually a blocked aerator, calcium buildup on the showerhead, or debris in the valve cartridge. For whole-house low pressure the cause could be municipal pressure levels based on your home’s location, a partially closed valve, corroded galvanized pipe, or insufficient pipe size. A pressure test after the water meter tells us exactly what we’re dealing with.
Can I increase my water pressure myself? Sometimes yes. Cleaning a blocked aerator or soaking a calcium-covered showerhead in vinegar are DIY fixes. Checking that all shutoff valves are fully open is also worth doing before calling a plumber. However if the problem is municipal pressure, galvanized pipe, or pipe sizing a licensed plumber is required.
What is a booster pump and do I need one? A booster pump increases the pressure of water entering your home from the municipal supply. If your home’s water pressure tests under 40 to 45 PSI and municipal pressure in your area is consistently low a booster pump is an effective solution. We test pressure before recommending one.
What’s the difference between low water pressure and low water volume? Pressure is the force of water at the tap. Volume is how much water can flow at one time. If pressure drops when multiple fixtures run simultaneously you likely have a volume problem — typically caused by undersized water supply pipes. Upsizing the water main or distribution pipes fixes volume issues.
Can galvanized pipe cause low water pressure? Yes. Galvanized steel pipe rusts from the inside out over decades. That rust narrows the inside of the pipe and restricts both pressure and volume. If your older London Ontario home still has galvanized water lines low pressure is often a symptom of pipe deterioration. Replacement is the only permanent fix.
How much does fixing low water pressure cost in London Ontario? It depends entirely on the cause. Cleaning an aerator costs nothing. A booster pump installation is a more significant investment. Replacing galvanized pipe is a larger project priced based on how much pipe needs replacing. Contact Triton for an honest assessment and quote based on your specific situation.
Book a Low Water Pressure Assessment in London Ontario
If your water pressure isn’t what it should be — whether it’s one shower or the whole house — Triton Home Service can diagnose the cause and give you an honest picture of your options.
Licensed Red Seal Plumber. 26 years in the trade. Serving London, St. Thomas, Woodstock, and Southwestern Ontario since 2010.
Book your low water pressure assessment with Triton
For reference: City of London Water System Information — City of London Ontario
Aron Oretan is a Licensed Red Seal Plumber and Steamfitter, UA Certified Instructor, and founder of Triton Home Service. With 26 years in the trade, licences in plumbing, steamfitting, and gas fitting, and five years teaching at Fanshawe College, he brings classroom expertise and field experience to every job in London, Woodstock, St. Thomas, and Southwestern Ontario. Phone: 226-270-6424 | tritonservice.ca
