It's frustrating to take a shower when the pressure is low, but it doesn't have to be that way. Knowing the possible causes of this problem will help you to avoid them or perform a quick diagnosis. Here are three possible causes of the problem:
Debris in the water can lead to low pressure even if there is no other problem with your shower system, since debris restricts water flow. For example, lime deposits from hard water can build up inside the showerhead, which reduces the flow of water. If your plumbing system is old, and it's comprised of metal pipes, expect rusty pieces to break off and clog your showerhead. Depending on your water source, algae in the water may also cause the blockage. Fortunately, this problem isn't difficult to solve since all you have to do is to clean out the aerator in the showerhead or replace the aerator (in the worst case scenario).
A leakage in any part of the plumbing system may reduce water flow not only in the shower but also in other water outlets. A small leak may not cause much of a problem, but a serious leak may affect your entire house's water pressure. Therefore, check all your water pipes for signs of leakage that may include these four:
- Damaged walls, paint, flooring or ceiling
- Signs of mold or mildew
- Constantly wet floors
- Unexplained increase in water bill
If this is the case, your shower's water pressure will normalize once a plumber plugs the leak.
The quality of your plumbing may also affect your water pressure. For example, low water pressure may be occasioned by small pipes that cannot supply all the water outlets in the house at the correct pressure. The probability of this being the cause of your low water pressure is even higher if you recently engaged in some DIY plumbing alterations; you may have used inadequate connections.
To confirm if this is the case, turn off other water outlets in the house and observe your shower's flow. If the pressure reduces only when other faucets are spewing water, then the culprit is likely inadequate connections. Contact a plumber to confirm the diagnosis and replace the relevant pipes with wider ones.
It's possible to have low water pressure due to other reasons other the three mentioned above. Call a plumber if you have ruled out the three issues above, and you still can't figure it out.