On mains (reticulated) water supply, low water pressure is usually caused by one of a handful of things:
- Pipe corrosion or scale build-up in older homes
- Pipework that was undersized for current demand
- A faulty or partially closed valve
- Too many fixtures drawing water at once
If your property runs on tank or bore water instead, a struggling pump is more often the cause – see the section below on bigger jobs. Whichever applies, working out whether the problem affects your whole house or just a single tap is the first step to actually fixing it, rather than guessing.
Is it low pressure everywhere, or just at one fixture?
Low water pressure at every tap usually points to your main supply line or pipework, while low pressure at just one fixture is usually local to that tap or outlet. Working out which one you have is the first step to fixing it properly.
Low pressure everywhere usually points to something affecting your main supply line – ageing or corroded pipework, a partially closed stopcock or valve, mineral scale gradually narrowing older pipes from the inside, or in some cases an issue with the supply coming into your property.
Low pressure at one fixture is more often local to that tap or outlet specifically – a clogged aerator or shower head, a fault with that particular fitting, or a partial blockage in the short pipe run leading just to that fixture. This is usually the simpler, and cheaper, of the two to fix.
If your pressure has dropped suddenly alongside any damp patches or the sound of running water you can’t account for, it’s worth checking for a leak before anything else – see our guide to leaks on your Hawke’s Bay property. Dealing with the opposite problem? Our guide to high water pressure covers what’s causing that instead.
Simple fixes worth trying first
The simplest fixes for low water pressure are cleaning or replacing the aerator, checking the shower head for scale, and confirming your stopcock is fully open. Try these first, particularly if only one tap is affected, since they cost little and often solve it.
- Clean or replace the aerator on the affected tap – mineral build-up here is one of the most common, and easiest to fix, causes of single-fixture low pressure.
- Check the shower head for scale blocking the holes, especially in areas with harder water.
- Confirm your stopcock is fully open – a partially closed valve after any recent plumbing work is an easy thing to overlook and a common cause of a whole-house drop.
- On a tank or bore supply, a clogged sediment filter is a common cause. See our guide to rural water filtration.
When it’s a bigger job
If the simple fixes don’t resolve your low water pressure, or the whole house is affected, the cause is usually further up the line: corroded or scaled pipework, undersized pipework, or a low incoming supply pressure that a pressure pump can help with. These are bigger jobs best assessed by a plumber. Here’s what each involves:
- Corroded or scaled pipework, common in older Hawke’s Bay homes with galvanised steel pipes, narrows the pipe from the inside and reduces flow throughout the property. This often needs partial or full pipe replacement to properly fix.
- Undersized pipework for your household’s current demand (more bathrooms or appliances than the system was originally designed for). If this is identified as the issue, you may need to upsize the pipes to properly supply your home.
- A pressure pump can help where your incoming supply pressure is genuinely low rather than restricted by your own pipework – common on rural or gravity-fed properties, including many running on tank or bore water. See our guide to rural water filtration and maintenance if a struggling water pump could be part of the picture.
Low water pressure troubleshooting checklist
- Check whether it’s one fixture or the whole house
- Clean the aerator or shower head on the affected tap
- Confirm your stopcock is fully open
- Check for signs of a leak (damp patches, running-water sounds)
- If it’s whole-house and unresolved, get your pipework properly assessed
Get it sorted
As Certified Master Plumbers, Gasfitters and Drainlayers, we diagnose and fix low water pressure in residential and commercial properties across Hawke’s Bay. From a quick aerator clean through to pipe replacement and pressure pump installation, whatever’s causing yours, it’s work we’re qualified and set up to handle.
Not sure which of these applies to you? Book a diagnosis and we’ll pinpoint the cause. Already identified a bigger job? Request a quote and we’ll put a plan together. Call us on 06 211 6462 either way.
