Can Two Showers Run at the Same Time? Plumbing Considerations Explained

So, is it possible to run two showers simultaneously? Yes, you can run two showers at once. But, it will reduce the flow rate and water pressure of showers. Normally, it is not possible to run more than one shower without disturbing its flow rate and pressure. In the case of temperature-controlled showers, both might not serve hot water.

In this article, we will discuss the reasons behind the reduction in water flow. In addition, the methods to minimize this effect while using hot water cylinder running two showers simultaneously will also be discussed. You will come to know more information if you go through this article. So, keep reading.

Can Two Showers Run at The Same Time?

If you’re wondering if can two showers run at the same time, the answer is yes. However, it also comes with certain side effects. Let us explain.

Can Two Showers Run at the Same Time
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Though two showers can run simultaneously at the same time, you won’t get a proper water flow through them. One shower running at one time will give you the required flow of water. If you start another, there will be pressure and volume loss in both of them.

The reason for the pressure drop is due to the friction between the pipe and the water. Friction loss increases with the increasing flow rate and pipe length. The greater the friction loss, the greater will be the pressure drop at the outlet. Thus, you’ll notice greater pressure drops in the shower that’s close to the water source.

The greater the volumetric flow rate at constant pressure, the greater the friction loss. When two showers are turned on at the same time, the flow rate of water at two pipe ends increases. This increased flow rate is yet another cause of pressure loss of water, when using two showers.

How to Maintain Water Flow in Both Showers Running Simultaneously?

It is possible to maintain a decent pressure of flow on both showers running at an instant. Methods that you need to follow to get this result are:

Can Two Showers Run at the Same Time? Plumbing Considerations Explained
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1. Internal Plumbing Pipe Size

The size of pipe coming into your house is normally 1 inch or ¾ inch. After that, it enters into a ½” pipe of your home. This reduction in ok pipe size will cause at least 75% decrease water pressure, and volume loss.

So, you have to upgrade the pipe leading to your main bathroom up to ¾”. As a result, it will increase the pressure at each shower head.

2. Checking Cold Water Tank Source

Can Two Showers Run at the Same Time? Plumbing Considerations Explained
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The output of a good pump is usually 5GPm. A showerhead generally uses almost 5GPM. So, if you use two showerheads, the output will be 2.5 GPM.

That’s why for maintaining 5 GPM per showerhead, you have to upgrade the good pump. You also can add a third cold water or water storage tank to increase it to a minimum of 10GPM.

3. The Thermostatic Shower Valve System

Can Two Showers Run at the Same Time? Plumbing Considerations Explained
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There are two kinds of shower valves. One is a pressure balance valve and another is a thermostatic. Pressure balance valves try to keep the pressure even in both shower heads. This causes a reduction in pressure.

On the other hand, the thermostatic valve has separate volume control for every shower head. If you use the thermostatic valve controls this, it potentially increases the pressure and volume in each showerhead.

4. Low-pressure Shower Heads

Can Two Showers Run at the Same Time? Plumbing Considerations Explained
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Showerheads with lower GPM operate under high pressure. Because even pressure the internal space of that shower is tighter.

This type of showerhead help to concentrate the water. They hold water in a small space while water pressure is increasing behind it. So, you can use this type of showerhead to maintain the required water pressure.

Can I Run Two Showers On The Same Water Line?

You can add two shower faucets on the same water line. But, the water pressure in both faucets will reduce while operating both at the same time.

Can Two Showers Run at the Same Time? Plumbing Considerations Explained
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If you want plumbing system to maintain constant pressure, you have to use a large supply pipe. Besides, the parallel arrangement can also help you in this case. But you’re still bound by your residence’s water supply size and pressure.

You should use low-flow shower heads for water saving. Moreover, you can also check the size of the water supply line, water meter, and water meter union. Then, try to increase the cold water tank size if possible.

The main water supply must have an installed pressure regulator. Now, try to measure the static pressure downstream of that regulator. Then you can decide if you e the regulated pressure.

Is It Possible to Run Two Electric Showers at the Same Time?

An electric shower consumes a significant amount of energy. As a result, it heats the cold water and supplies warm water through the electric shower head.

Can Two Showers Run at the Same Time? Plumbing Considerations Explained
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Electric showers can be of various electric shower amps and wattages. These varying rating powers ensure the desired flow rate of warm or cold water throughout.

Normally electrical showers are of 8 and 9 KW. They take almost 40 electric shower amps when they run individually. If you run two electrical showers at once, it will take a total of 80 shower amps. This will cross the rating of the main house fuse. Thus, it will cause the main fuse to blow.

Can I Run Two Shower Heads Using One Valve?

Can Two Showers Run at the Same Time? Plumbing Considerations Explained
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Yes. You can run two shower heads using one valve. But you have to consider the size of the tubing and the number of fittings. Only then, you can run two showers using one valve without changing the flow.

½” supply tubing is sufficient to supply an ample amount of water to both shower heads. A showerhead can supply a maximum flow of 2.5 GPM. A supply tubing of ½” can feed 5 GPM. In this case, supply tubing must not have too long a run, flow rate restriction due to corrosion, and too many twists and turns.

If the valves pass through is above 5GPM, it can feed the two shower heads. So, you can run two showers at once easily using one valve.

On the other hand, the supply tube may have many flow restrictions. In this case, you have to use showerheads with less flow-through.

Can I Run Two Showers With A Combi Boiler?

Can Two Showers Run at the Same Time? Plumbing Considerations Explained
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Combi boiler provide both central heating and hot water in multiple showers with the same system. We won’t recommend you to operate two showers at once with a combi boiler.

You will be able to run one very low flow shower heads at once because the first one will lose water pressure after opening the second shower. Two showers of very low flow rate might be possible.

It is not allowed to use a pump with a combi boiler. Thus, the solution to this problem is not cheap and easy. You will need to fit high flow rate multi-point for running hot water between two showers.


Can 2 people shower at the same time?

An ordinary tank style water heating unit can usually start providing 2 showers at a time but the heated water pressure in the tanks may run out before the showers have completed; that’s not true on the Tempra 24+.

Can you run 2 electric showers at once?

Electrical showers typically have an output rating from 8 kW to 9 kW taking in 40 amps for showering while running. If the electric shower itself is powered by two electric units the total charge is 80 shower amps which exceeds the power output in the house which might cause blowing.

Can you run two showers off one pump?

There are 2 showers at home. Is it necessary to have water heater in them supplied with the pump that is in the pump? Okay? Yeah.

Is it okay to take two showers?

In some cases, you could even have two or three showers depending on time. No one can argue that cleanliness is important to a family. Although some people take a shower every night, most of the time it’s not necessary.


So. can two showers run at the same time? As you can see, running two showers simultaneously without pressure loss is not possible generally. You will get a very poor water volume and a reasonable water pressure if you do so.

But, you can solve this problem by using a few techniques. If you follow those ways, you will get decent maintain water flow in both showers. Still, you will get less flow than the flow restriction that you will get if you run only one shower at one time.

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