Water pressure is measured in 'bar', and generally speaking, anything 0.3 bar or below requires a low water pressure tap or shower, and anything at 1.0 bar or above requires a high water pressure tap or shower.
Water systems which operate at 1.0 bar pressure (10 m of drop) or greater are considered high pressure systems. Those with a pressure less than 1.0 bar are considered low pressure. When you're ready to choose a tap or shower, you'll find the water pressure it's suitable for will be clearly labelled.
Simply go to one bathroom, and turn on all faucets/showers. Once all the fixtures are on, flush the toilet to see if the water drops pressure from the sinks or shower heads. If water pressure drops while the toilet is filling up, there might be an issue. You should complete this process for all rooms that have water.
Find the spigot closest to your source of water. Make sure all the taps and other water uses are turned off in your house. Now turn on the spigot and see how long it takes to fill the bucket. Dividing the number 60 by the time to fill the bucket will give you the gallons per minute number.
Normal water pressure is generally between 40 and 60 PSI. Most homeowners prefer something right in the middle around 50 PSI.
In general, residential water pressure ranges between 45-80 psi (pounds per square inch). If your water pressure is under 40 psi, it's considered low. A psi between 20-30 is considered very low, and under the minimum water pressure required by most building codes.
Low water pressure can present itself in various ways, all of which can cause significant inconveniences. Taps may take forever to fill your bathtub, or the showerhead may not spray water efficiently. Either way, your daily activities are slowed down. Sometimes the issue comes from the municipal water supply.
Place the measuring jug under the tap. Then, turn the tap on full. Time how long it will take for the jug to fill up. If it takes more than 6 seconds to fill it up, then the water pressure is low.
Partially Closed Valve
One of the most common issues that can lead to low water pressure problems is that the water is being obstructed by one or more partially closed shutoff valves. Typically, a home will have one main shutoff valve located inside the house.
If there's an accumulation of sediments in your hot water tank, it can lower your water pressure. The presence of kinks in the flexible water pipes used in water heaters can result in low water pressure. If the shut-off valve isn't fully open, water pressure can drop.
If you have low water pressure in all your plumbing fixtures, the issue is almost definitely with your water supply or your pipes. However, if it's one or a few fixtures that seem to have a low flow, you may want to check out the fixtures.
Take the amount of water in the jug in litres (e.g. 0.8 litres) and multiply this by 10. This will give you your flow rate in litres per minute (e.g. 0.8 litres x 10 = 8 litres per minute). If your flow rate is less than 10 litres per minute, you may have what is considered low water pressure.
Residential water pressure tends to range between 45 and 80 psi (pounds per square inch). Anything below 40 psi is considered low and anything below 30 psi is considered too low; the minimum pressure required by most codes is 20 psi. Pressures above 80 psi are too high.
The maximum recommended water pressure for homes is 80 psi; any pressurization exceeding this amount will result in thousands of wasted gallons of water each month.
This is a serious concern—water pressure that's too high is difficult to contain, and could leak to plumbing leaks, worn seals, and damaged fixtures. It could even shorten the lifespan of your appliances that depend on a water connection like your washing machine, ice maker, dishwasher, and more.
Most residential plumbing systems are designed to handle 40 to 60 PSI of pressure, with 80 PSI being the typical maximum and anything over 100 PSI being possibly detrimental to plumbing components.
In addition to the mains stop valve outside the home, you'll have one inside. Your internal stop valve is most likely beneath the kitchen sink. Your external stop valve is owned by the water company. If it's open yet the pressure here falls below one bar, it's their responsibility to improve it.
Low boiler pressure can wreak all kinds of havoc on your heating system - it could leave you with no hot water and no heating. Luckily, it's a relatively easy fix that you can do yourself at home.
Hot Water Heater Problems
Believe it or not, and this is believable, your hot water heater can affect the pressure for both hot water and cold water.
You can increase water pressure by loosening a locknut on the valve. Contact a well-pump technician: If your house is on a private well, poor water pressure could indicate a problem with the captive storage tank or the pump. It's best to have the well system serviced by a qualified well expert.
Normal psi for a home pipe system is between 30 and 80 psi. While you don't want the psi to be too low, it violates code to be above 80. Instead, you should aim for a psi that's between 60 and 70.