The most common cause of low shower pressure is a blocked showerhead, as a result of limescale build-up. These blockages obstruct the water flow, leading to reduced pressure over time. Most showers are fitted with a filter, protecting the pipework from debris, but this can become partially blocked by scale.
A simple way to increase the water pressure in the showerhead is to purchase a new shower head – they're inexpensive items – and look for the washer inside. This is designed to restrict the water flow, but you can widen this with a drill until the water flows properly.
For water conservation purposes, most plumbing codes require faucets and showering devices to not exceed a certain maximum flow rate. Removing the flow restrictors could cause these devices to no longer meet these codes.
What does a flow restrictor look like? Before you remove the flow restrictor from your shower head, you need to know what it looks like. A water flow restrictor is usually a flat, circular, plastic piece. The center of the restrictor is shaped like a star, or similarly shaped, and comes in a variety of colors.
If the water from your showerhead is shooting out in all directions, or your flow has become almost nonexistent, the holes in your showerhead are probably clogged with hard water minerals and soap residue.
Look on the main supply pipe near your water meter for a conical valve that has a bolt sticking out of the cone. To raise pressure, turn the bolt clockwise after loosening its locknut. Keep an eye on the gauge to make sure the pressure is within bounds, then retighten the locknut.
Lower pressure could be more severe than you imagine, potentially involving serious problems like leaking or cracked water pipes and may require professional intervention before snowballing into a home plumbing disaster.
The short answer is low water pressure in your home arises due to a number of causes. Some include a shut or blocked water meter valve, mineral buildup clogs pipes, corroded pipes, or even a crack in the main city supply pipe to your home.
Shower and bathtub shutoff valves are usually hidden behind an access panel. That panel can be in the bathroom, the room behind the bathroom or the ceiling of the room below. If you don't have an access panel, it could be hidden behind the wall.
More often than not, no water pressure in the shower, bathrooms and other parts of the house are caused by your pipes or drains being blocked. You may also have a broken or leaking pipe. If this is the case, you may notice a damp smell, an increase in your water bill or water on your carpets or walls.
Once you've installed your shower head, switch on the cold water supply and allow the water to run for between 10 and 15 seconds. After this, do the same with the hot side. If you are performing a shower valve test with air, simply follow the same procedure.
Showerheads clog over time because of a buildup of mineral deposits—specifically calcium. You may notice water spraying out of the nozzle in random directions, part of your showerhead is completely clogged, or poor water pressure.
Clogged Shower Head
Usually, this is a result of a build up of calcium or lime scale. These mineral deposits build up over time, accumulating on shower heads. This often clogs the water coming from the shower head causing lower water pressure or even an entire stoppage of water altogether.
You have leaks or drips
For example, water might seep out of parts of the valve; you may even see some water on the floor under it. This might indicate a faulty seal or a corrosion problem. If you have a TMV in your shower, then a faulty valve can make the shower drip even when it is off.
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.
No, flow restrictors do not change pressure, but they do take pressure into account. Flow rate is dependent on three factors: the size of the outlet, the upstream pressure, and the downstream pressure. The pressure differential between both sides of an outlet determines how high the flow rate of a fixture is.
If you've just installed a brand-new showerhead and find that the pressure is suddenly lower, it's probably because you've purchased a water-saving showerhead. Check the labels around the rim, or perform the showerhead GPM test as described below.
Federal, state, and local governments regulate shower head GPM flow rates, because the potential for water and energy savings are significant. A standard 2.5 GPM shower head uses 2.5 gallons of water each minute. That's 25 gallons for a 10-minute shower.
A typical shower valve replacement costs around $375. You could pay as little as $20 to replace the valve or you could spend as much as $750. Just how much your replacement valve installation costs depends on the type of valve you're replacing, the extent of work and the going rates for plumbers in your area.
A properly installed shower valve should serve you well for a long time. Even if you live in an area with hard water that causes limescale build-up in your appliances, you can expect to have a shower valve work well for about four or five years.