If you find a measure that is between 10 and 15 litres per minute, that's not bad but can be improved, while a flow above 15 litres per minute is good. Armed with this information on your water pressure, you can check the specifications of the tap you intend to buy and make sure it is a good match.
Kitchen faucets may temporarily increase the flow above the maximum rate, but not to exceed 2.2 gallons (8.3 L) per minute at 60 psi, and must default to a maximum flow rate of 1.8 gallons (6.81 L) per minute at 60 psi.
A low-flow sink faucet must not exceed a maximum of 1.5 GPM. A low-flow toilet must use no more than 1.5 gallons per flush (GPF).
Low-flow faucets
Faucets that meet energy efficiency standards for WaterSense mustn't use more than 1.5 gpm, a 32% decrease in flow rate over the federal requirement. Reduced flow faucets often make use of flow restrictors or faucet aerators to reduce the flowrate of the water.
The average flow rate for faucets is between 1.0 gpm and 2.2 gpm. In the US, the maximum flow rate for kitchen and bathroom faucets is 2.2 gpm at 60 psi. In more environmentally regulated areas, the maximum flow rates are further restricted. For example, Georgia is down to 2.0 gpm and California is at 1.8 gpm.
All kitchen sink faucets should comply with federal standards for a maximum flow rate of 2.2 gpm (8.3 lpm); a flow test does not exceed 0.4 gal.
A 2.5 gpm shower head will have a better pressure and shower experience than a 1.5 gpm shower head. A 1.8 gpm shower head would have a better pressure and shower experience than a 1.0 gpm shower head. Another drawback of low flow shower heads boosting the pressure is the temperature instability.
Please keep in mind that all new faucets since 1994 are restricted to conserve water per EPA code mandates. Older faucets had no restrictions. Beyond intentional flow restriction, new installations can sometimes have reduced flow if the lines are not flushed prior to installation of aerators or shower heads.
The water flow in plumbing is determined by the pipe width and the pressure. To put it into perspective, smaller pipes supply water to plumbing systems at a lower flow rate than larger pipes. The pressure also affects the flow rate. The greater the water pressure, the greater the water flow rate.
The savings with a low-flow faucet
Modern low-flow faucets reduce the water flow by about 30%, and sometimes more. The average faucet runs 2.2 gallons per minute, while low-flow models run 1.5 gallons per minute.
Higher GPM will help you get the job done faster. For most homeowners, identifying your ideal PSI (whether low or high) is a good start. Once you have the PSI you need, then look for higher GPM numbers to get better efficiency.
If you're looking for the most pressure, go for the 2.5 GPM Flow Rate, unless you are restricted because you reside in California, Colorado or New York. Again, this has been the Maximum Flow Rate since 1992. The step down from there in Flow Rate is 2.0 GPM.
How Many Gallons Per Minute Do You Need for Your Home? This is a loaded question, that really comes down to preference and the number of individuals that are in the home. The average household needs 100 to 120 gallons per person per day, and a flow rate of about 6 to 12 gallons per minute.
Low water pressure in sink faucet
Clogged aerators and clogged cartridges are two of the most common causes of low water pressure in a sink.
Clogged aerator screen
The aerator is the first to check when a faucet has low water pressure. Most faucets have aerators at the base or inserted inside the spout. Sediments, mineral deposits, or small debris can clog the aerator over time, which results in low water pressure.
The typical residential water flow rate for small households is between 6-12 gallons per minute, so unless you plan to add extra kitchens, bathrooms, or laundry rooms to your home in the future, your home will never need to exceed that final GPM, assuming your flow rate is already normal.
Most often homeowners complain about low pressure; however, having high pressure can result in expensive damage. The pressure level can vary, but 60 PSI (pounds per square inch) is recommended for most residential homes. Water pressure should not be higher than 80 PSI.
That's a common misconception. A lower flow rate does not mean that your shower will have less pressure. Water flow (gpm) refers to how much water is coming out, not how fast or how hard it's coming out.
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.
If your showerhead is labeled 2.5 GPM or less, you have a low-flow showerhead. Any showerhead labeled 2.6 GPM or above is a high-flow showerhead. If your showerhead doesn't have a label, try this trick to determine the flow rate. Place a bucket or container with a 1-gallon marker under the showerhead.