Understanding Water Pressure When Using A Private Supply

There’s nothing more frustrating than trying to wash your hair in a trickle of water.

Low water pressure is inconvenient, whether you’re at home trying to wash dishes or running a business that relies on consistent water flow.

If you’re struggling with water pressure issues you’re not alone. Depending on where you are in the country your water pressure might be low if Scottish Water reduce pressure to prevent leaks.

Edinburgh and parts of Clackmannanshire have recently struggled with low pressure. While Scottish Water try to fix such issues there is no legal obligation for them to do so. This can leave the domestic user feeling frustrated every time they turn on the tap or shower. The good news for those using a borehole or well water system instead of mains water is that there are lots of solutions to low water pressure when you have control over your plumbing system.

This expert guide will explain everything you need to know about water pressure on a private supply, from what to do when your pressure suddenly dips to how to measure water pressure and optimize the flow rate.

Read on to discover the common causes of low water pressure and how solutions like water booster pumps can help.

What is water pressure?

Simply, water pressure is the force that moves water through a water pipe.

Water pressure determines the flow of water through your tap or shower outlet.

Water pressure is measured bars. 1 bar represents the force needed to push warer to a height of 10 metres. Your shower head and taps come will typically have a pressure rating between 0.1 and 3 bar.

As you may already know, water pressure can vary significantly between homes in various places and even on different days.

Generally, mains water pressure is determined by where you live relative to the nearest reservoir/source. If you live on a hill, the water pressure may be lower than the house at the bottom.

Those using a private supply can experience low water pressure for several reasons, which we’ll look into now.

Why is my water pressure so low?

Here are the most common reasons for low water pressure when using a private supply.

Clogged Fittings

The first thing to check for before calling an expert is clogged appliances and fittings. Blocked pipes are another culprit. If you feel confident you can perform these tasks yourself. Otherwise, call a certified plumber.

Wrong shower heads and taps

Low pressure water systems need the right tap and shower head to work efficiently.

A lower pressure system might achieve a stronger flow from a simple change of fittings.

Old or Narrow Pipes

Narrow pipes and pipework that hasn’t been upgraded or maintained can cause a drop in water pressure.

If your pipes aren’t wide enough then water can’t travel through them adequately. In this case you’ll need to speak to a water hygiene company whose trained experts can upgrade your water system’s pipes.

You might be eligible for a grant of up to £800 from the Scottish Government to upgrade old pipework. Read our blog to find out more.

Water Quality

We always stress the importance of regularly testing the water of your private supply, and this is another reason!

Did you know that calcium and iron can cause a buildup in your pipes, fittings and water tank? This can prevent you from achieving high water pressure.

Trusted water companies can test your water for mineral contaminants and put measures in place to prevent buildup and loss of pressure.

Combi boiler system

A combi boiler system can affect the efficiency of your water system.

Sometimes it’s a leak that causes a drop in pressure, in which case you need to re-pressurise the system.

You can call a professional to help or re-pressurise yourself using the boiler manual.

Gravity fed system

Simple gravity can often be the cause of low water pressure.

Depending on where it’s placed, a well pump might have difficulty pumping water to the top floors of your home. If you’re considering installing a private water supply, you should consult with a local company who will be able to advise on the best placement for your well or borehole.

Of course, in the case of natural water sources, you can’t simply move them. And what if you’ve already forked out for a borehole?

In these cases, we recommend trying a water booster pump.

Water Booster Pumps – the answer to water pressure woes?

Weak flow from a tap or shower and toilets that fill and flow slowly can benefit from a water booster pump.

A water booster pump can improve water flow rate from your property’s water tank. It works by providing added pressure to distribute water around your home or business property.

Water booster pumps are a great way to achieve higher pressure if your property draws its supply from a well.

High quality booster pumps start at around £300. The amount and size you need will be dependent on your property and how many use the supply. A private water company can help you install adequate water pump boosters.

Why not get your water tested at the same time? You’ll not only benefit from power showers but the peace of mind that your water is free from contaminants.

What should my water pressure be?

The minimum water pressure standard that Scottish Water tries to maintain is 1.0 bar where the pipework enters your home (usually found at your property boundary).

Anything above 1.0 bar is considered high pressure while anything under one bar is low pressure.

Another rule of thumb is that you should be able to fill a 1 gallon water jug from the kitchen tap in 30 seconds.

You’ll certainly know there’s a problem if your cursing how long it takes to fill the kitchen sink or you haven’t had a decent shower due to weak water flows!

What water pressure can I expect on a private supply

The water pressure considered optimal for households is 15 litres per minute.

Between 10 – 15 litres per minute is fine, but a business that uses water as part of a manufacturing process or for agricultural reasons, might need more.

Another water pressure gauge you might have seen is pounds per square inch. Setting your pressure gauge to between 40-60 pounds per square inch (PSI) is recommended.

How do I check my water pressure?

Here’s a simple method to check your water pressure:

• Find the timer app on your phone
• Place a 2 litre water jug under the a tap or shower head
• Switch on your timer at the same time as the tap
• Run the tap for 6 seconds to fill the jug
• Take the amount of litres collected and multiply by 10. This will tell you the rate in litres per minute of water produced
• Less than 10 litres per minute is considered poor
• Between 10 -15 litres per minute is average
• Over 15 litres per minute is good

If you’re unsure about the above process or find it hard to get an accurate result, contact your local private water company for help.

What’s the difference between water pressure and water flow?

Water pressure and water flow are two different issues.

The best way to describe the difference between the two is that water flow is how much water comes out of your pipes and water pressure is how hard the water comes out.

Water flow rate can often be improved by fixing tap fittings and pipe openings. Cleaning sediment buildup and replacing narrower pipes with a wider plumbing system will also help.

The number of taps being used at once also affects water flow rate because your system has to work harder to disperse pressure evenly.

Further information

To learn more about private water supplies read our blog for tips on how to save money with a private supply and grants for upgrading lead pipes.

Water pressure FAQs

The following list includes the commonest questions we have about water pressure and our expert response to them.