Low water pressure can make showers frustrating and ineffective. While low flow shower heads are in vogue right now, there’s a difference between saving water and suffering with low pressure. Federal regulations dictate water pressure remain under 2.5GPM (Gallons Per Minute) at 80psi, but anything below 1.5GPM feels unproductive. This gives us an ideal range of 1.5-2.5GPM, with many people preferring water pressure of around 2.0-2.5GPM. Poor water pressure can also be a sign of plumbing problems that go beyond the shower head.
There’s a simple way to test your water pressure. All you need is a 5-gallon bucket, a clock or timer that displays seconds, and a calculator for some simple math. Place the bucket in your bathtub and turn the shower on full blast. Use your timer to track the number of seconds it takes to fill the bucket. Then break out that calculator and divide 5 (gallons) by the number of seconds it took to fill the bucket. Multiply this by 60 (seconds) to get the number of gallons of water per minute (or your GPM).
Tracking Down the Pressure Problem
If your water pressure is below 2.5GPM, you’ll first need to determine if this is due to your shower fixture, or if it is the symptom of a bigger plumbing problem. Take off the shower head and repeat the water pressure test above. If the water pressure improves, you can simply buy a new shower head. However, if it is the same or close, you may have a problem in your pipes.
To find the source of your water pressure problem, start by checking the pressure in other parts of your house. For instance, you can disconnect the line to the toilet and test that or check the water pressure in your kitchen sink.
If the pressure is low in your whole house, check for any shut off valves that may be partially closed along your pipe. If you find a pressure reducing valve, loosen the nut, turn the adjustment screw clockwise to increase the pressure or counterclockwise to decrease the pressure, and then tighten the locking nut back.
If you do not find a valve, you may have to call a plumber. If the pressure problem is limited to your bathroom though, there are a few places you can check for blockages first. Take off hot/cold water handle and remove the bathtub facet to check for obstructions. If you’re feeling especially handy, you can also remove the retaining nut, cartridge, valve, etc. and clean them all out. While they’re out of the way, grab your bucket and check the water pressure again. If you do not find any obstructions or build up, and the water pressure is still low coming straight out of the pipes, the shower valve itself may be clogged. In that case, you will probably need to a new rough-in valve, and a plumber to install it.
Unless you have the experience and tools of the trade, it’s a good idea to hand any significant plumbing problems or upgrades over to a plumber. That includes water pressure problems that can’t be fixed at the faucet, because what might start as a minor annoyance could turn into a water damage nightmare if tended to incorrectly. The professionals at Biard and Crockett perform these routine kinds of repairs all the time. Give us a call to replace any needed valves, or to locate or clear any kind of blockage in your plumbing. If you’re shopping for a new rough-in valve or any material for a plumbing project, we have a retail store with all of the parts and materials you may need. Regardless of the cause of your shower water pressure issue, we’ll bring you back up to speed in no time.