5 Plumbing Tips to Fit a Water Pressure Pump Under Your Bath

(Last Updated On: November 20, 2023)

It can be challenging to fit a water pressure pump under your bath because of space limitations. However, this can be a fairly easy DIY project.

Various technologies can exist inside the bathroom. You will likely be familiar with some of these, like toilet hand dryers, automatic soap dispensers, and water heaters. However, you may be less familiar with a water pressure pump.

Water pressure pumps are indispensable, as they allow the water from the tank to be pushed out with high pressure through the sink and bath taps. This pressure ensures that dirt can be cleaned off adequately and makes showers enjoyable. After all, showers are only pleasant when we can control the flow and temperature.

There are various places where you can fit a water pressure pump; one location is underneath the bath. While this is quite an unusual location to fit it and is only sometimes recommended, it may sometimes be necessary if there is no place to put it as assessed by an expert plumber or builder.

Not to worry, we will provide you with valuable tips that will allow you to fit a water pressure pump under your bath correctly and safely. Let’s dive in.

Water pressure booster pumps.

To fit a water pressure pump under your bath, choose the smaller ones that are suitable for a shower.

Whole House Or Shower Booster Pump?

A whole house pressure boosting pump is normally too large to place within the confines of a tub enclosure.

Usually they are placed close to where the water enters the house. For homes with well water, that would be after the pressure tank.

Shown below is the Simer 4075SS-01 3/4 HP Whole House Pressure Booster Pump.

Simer 4075SS-01 3/4 HP Pressure Booster Pump
  • Powerful 3/4 HP Pressure Booster Pump includes 6-foot 115-volt power cord
  • Works as needed; auto-activation when water runs
  • Rust and corrosion-proof stainless steel
  • Already set-up and ready for installation
  • Provides up to 40 PSI of additional pressure

However, a shower presssure booster pump can be placed within the tub enclosure.

Also, since they are smaller and less powerful, they are quieter and produce little if any vibrations.

To boost the water pressure in a shower use the KOLERFLO Water Pressure Booster Pump KF301.

KOLERFLO 120W Water Pressure Booster Pump 115VAC,396 GPH,21.7 PSI Household Automatic Home Booster Pump with Water Flow Switch for Home Kitchen Bathroom Irrigation(H15GR-15)
  • Applicable to the duplex apartment,suburban villas,water heater pressurized,household water pressurized, and the solar water heater pressurized. Our water pressure pump especially suitable for water heater pipe pressurization with insufficient water pressure, to prevent water supply from being cold.
  • Max Pressure: 1.5bar (21.7 PSI);Max Flow Rate: 396GPH(25L/min), Max Head: 49.2ft(15m); Connection size: 1/2″ NPT; Liquid temperature range: 0 F- +212 F.the water boost pump with flow switch can automatically adjusts to your needs, Increase the pressure of household water tank and keep a steady pressure.
  • Easy installation, only need a wrench to connect the pump, saving you the cost of plumbers; the water booster pump is also Energy Saving ;Easy Operate and Silence Working.
  • Powerful 120W Motor, High Quality Water flow switch and full brass fittings included, All-in-one unit to make the water booster pump durable and provide enough water pressure for home use.
  • We provide 30 days free return and 3 months fittings parts replacement for our water boost pump.If you have any problems for using our products,feel free to contact with us at the first time,we’ll made you satisfied with your purchase.

 1. Ensure the bath access panel is removable with tools.

If you fit a water pressure pump under your bath, you must ensure that the bath access panel is accessible. This way, if anything goes wrong, you can access the pump easily and get it repaired.

However, you must still get the panel secured in place and ensure it is not easily removable by hand. A loose-fitting panel will mean that water can leak inside, which can be an issue.

Instead, get the panel fixed in place and ensure it is screwed tightly. This way, it will still be easily accessible with tools, but secure enough to not allow water to collect underneath the bath.

 2. Take measurements of the water pressure pump and the area underneath the bath.

There is generally a restricted amount of space underneath the bath as opposed to other areas where you might fit a water pressure pump. In such a case, you will want to ensure that the water pressure pump you buy will fit properly, by taking accurate measurements of the area before purchasing.

Even if the measurements suggest the pump will fit, you should leave some room for ventilation and ease of access in case maintenance is required.

Additionally, you will have to make sure your pump isn’t in contact with pipes that are not connected to it.

 3. Mount a whole house water pressure pump on a solid base.

Mounting a whole house pump on a solid base is crucial, as whole house pressure pumps are powerful machines that create a lot of noise and vibrations.

These vibrations can easily pass through a non-stable base, and can cause any nearby plumbing to get damaged.

Damaged pipes will lead to leaks and water damage, which can be devastating. Therefore, ensure that the pump is on a solid base. The vibration reducing pads shown below will keep the water pressure pump quiet.

4 Pack Rubber Isolation Feet Pads Thick Rubber Washers 1.5 Inch Od 0.5 Inch Id 0.4 Inch Thick Mechanical Vibration Damping Pads Anti Vibration
  • The damping washer is made of high-quality rubber material and has good water, oil, acid, alkali and high temperature resistance
  • Excellent Texture: made of rubber material, these isolation pads are wear resistant and tough, not easy to damage, suitable for long term use; More importantly, it can absorb most of the vibration
  • Each washer has an outer diameter of 3.81 cm/ 1.5 inch, an inner diameter of 1.27 cm/ 0.5 inch and a thickness of 1 cm/ 0.4 inch
  • Rubber isolators help absorb impact and noise and have excellent resistance to aging,they will not harden or crack over time. Use them on audio subwoofer and electronic equipment to prevent skipping and interference

If the ground underneath the bath is made of concrete, that can act as a solid base. Otherwise, you will have to install a new solid base or mount the pump on the foundation wall.

3.5 Mount a shower water pressure pump on a solid base.

Being smaller than a whole house water pressure booster, this size pump can be placed on a typical house floor. However, these shower pressure boosting pumps also make noise and create vibrations when running.

Next we have a bathroom pressure boosting pump with vibration reducing feet included.

Dreyoo Water Pressure Diaphragm Pump Industrial 115V, Self Priming Pump 4 Gpm 45 Psi include Power Plug, Fittings Strainer Filter for Kitchen Bathroom RV Marine Yacht Caravan, Garden Hose
  • Utility Pump Features: 115V AC water pump features 4 gallons per minute water flow, pressure switch is set to 45PSI, 0.8 Max amps. So easy that automatically opens when turn on the water tap, stops when turn off the water tap
  • Safe and Smooth: Our pump have certified to CE, stable and durable, smooth self priming with silent operation and can run dry without damage, thermal overload and ignition protection. Tip: To avoid leakage to the pump rotor in case of some product failure, the correct operation is to put the pump head down or flat during when installation
  • Industrial Workmanship: features industry standard fittings, power plug and aluminum alloy mounting base to directly replace similar common water pressure pump. Please connect all parts closely to avoid leakage or combine seal tape with our pump strainer to better prevent leaks on pipes and plumbing
  • Wide Application: Great for use in kitchen and bathroom. It is also the great partner of camper, sprayer, garden sprinklers, fertilizers, sprinkler faucet and agricultural irrigation as you like
  • Why You choose Us: High quality home and industrial facility should be available to everyone. You’ll get 1 x AC Diaphragm Water Pump, 1 x 1/2 inch Twist-on Water Strainer (includes 50 mesh stainless steel screen), 2 x Hose Fittings, 1 x User Manual, 1 x Box Container

 4. Remove water before pump installation.

Pump installation will require you to cut into the main water line. However, before you can do this, you will have to drain any existing water within the piping.

You can do this by shutting off the water flow by closing the main water valve. After that, open the lowest faucet in the home and remove all the water until the flow stops.

After you have cut into the pipe, there may still be some water left between the lowest faucet and the cut location. To remove it, you will have to open the highest-level faucet to bring in air, allowing the remaining water to drain.

 5. Install a pressure relief valve and low-pressure cutoff switch.

It is recommended to install certain safety features when fitting a water pressure pump.

The first is a pressure relief valve, which will help remove extreme pressures that can lead to catastrophic failure and damage. It ensures that the pressure in the piping remains below a specific limit.

Merrill MFG PRVNL50 1/2″ No-Lead Pressure Relief Valve, Brass
  • Pressure relief valves are for protection against excessive pressure
  • 1/2 in. male NPT x 1/2 in. female FPT
  • Lead free brass with stainless steel control springs
  • 1/2″ Line Connection, 75 PSI
  • Not for use with water heaters – Cold water systems only

The second one is a low-pressure cutoff switch that will shut off the pump automatically when there is little to no water running in the pump.

Some pumps can explode when such a case occurs, and low-pressure cutoff switches will ensure this does not happen.

SNS 1/8 Inch NPT Male Thread Pneumatic Adjustable Diaphragm Type Pressure Switch Normally Open and Closed Integrated QPF-N1
  • Made of high quality aluminum materials, firm with long service life
  • Type: Adjustable Pressure Switch
  • Normally Open and Closed Integrated
  • Working Voltage : AC110V, AC220V, DC12V, DC24V, Max. Working Current: 0.5 A, Pressure range: 15-145psi(0.1-1.0MPa), Max pulse number: 200 Cycle/Min
  • Used to control the pressure of the pump, keeping them in normal operation


To conclude, fitting a water pressure pump under the bath may be unusual, but it is certainly possible and may even be recommended by an expert, depending on your situation. In such a case, there are certain tips you should follow for optimal fitting.

You should ensure the bath access panel is fixed but still easily accessible with tools in case repairs are needed on the pump.

Take measurements of the pump and the area underneath to ensure that the pump fits appropriately.

Mount the pump onto a solid base to ensure vibrations don’t damage the piping and the surrounding area.

Remove water before pump installation by opening the lowest faucet, cutting the pipe, and opening the highest faucet to let in air.

Lastly is the YOUNGTREE Water Pressure Booster Pump with vibration reducing feet.

YOUNGTREE 110V Water Pump with Pressure Switch include Power Plug 5.5 GPM 70PSI 110VAC Water Pressure Booster Pump for Home Kitchen Bathroom RV Marine Yacht Garden Hose
  • FLOW OF 5.5 GPM – The diaphragm pump provides high volume water flow with reduced pump cycling and smooth flow. Self-Priming up to 9.8 vertical feet, lift up to 125 feet. The flow of water makes it perfect to use in various settings.
  • AUTOMATIC PRESSURE SWITCH – Equipped with an on demand pressure switch which turns it on immediately when the faucet on. The optimal pressure is set at the factory (70PSI), but you can still adjust it according to your needs.
  • LONG WORKING LIFE – The water pump certified to CE, comes with corrosion-resistant valves and offers thermal overload protection to stay in excellent condition. Support run dry without damage.
  • MULTIPLE APPLICATIONS – Mainly use for RV water system, agricultural irrigation, showers & home water system, camping and ect. So easy to install and use.
  • OUTSTANDING AFTER-SALES – If you are dissatisfied with your purchase for any reason, you can contact us through your order, we are always there. NOTE: It is normal to have residual water. We require that every water pump must be tested before leaving the factory to ensure 100% quality guarantee.

Install safety features like a pressure relief valve and low-pressure cutoff switch for optimal operation.

We hope this article proves informative and enables you to fit a water pressure pump under your bath properly and safely. Thank you for reading!

Related article: Well Pressure Tank Guide: (DIY) Problems, Sizing, Types, PSI

Last update on 2024-02-23 / Affiliate links / Images from Amazon Product Advertising API

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