How Does an Upflush Toilet Work

An upflush toilet is engineered to eliminate the need to install expensive plumbing systems. While the interior of an upflush toilet is hardworking machinery, the exterior is a fashionable complement to any bathroom decor.

But how does an upflush toilet really work? In this guide, we illustrate how upflush toilets function and why you may need one in your home or temporary structure. You can also go through our upflush toilet review guide to compare some of the best brands on the market today!

How Macerating Toilets Work

The main differentiating feature of an upflush toilet from standard toilet fixtures is the waste discharge mechanism. The key components of a macerating toilet include a macerator/pump and a small-diameter pipe.

The muscular macerator features a rotating blade that shreds and grinds all solid materials like human waste and toilet paper. When the solid materials are mixed with flushing water, they turn into a fine slurry that easily moves upward through a narrow pipe.

An upflush toilet also has an electric-powered pump that pushes the fine slurry upward under high pressure. By utilizing a small-diameter discharge pipe (usually as small as 3/4″ in diameter), an upflush toilet solves many structural problems since the pipe can be run virtually anywhere without digging up concrete walls or floors.

The fine slurry can move easily through the narrow pipe to your normal sewage system, holding tank, or septic tank.

Who Needs an Upflush Toilet?

Wondering whether an upflush toilet system will work for your specific project? The simple answer is, it depends on your individual situation.

Upflush toilets are ideal for both residential and commercial use. They work well for households looking to expand and increase the value, or rental properties looking for extra usability without requiring additional maintenance.

Some upflush toilet systems are also strong and durable enough to be integrated into commercial establishments since they can accommodate extended use.

SaniCUBIC grinder pumps such as the Saniflo 099 Sanicubic 2 Vortex system are powerful enough to grind and pump for multiple fixtures within an entire building simultaneously.

There is literally no limit to the applications of these brilliantly engineered Upflush toilet systems!

How to Install an Upflush Toilet 

If you’re wondering how to install an upflush toilet, this section highlights the step by step approach to help you out.

Unlike installing a traditional toilet that involves breaking concrete floors, installing drain pipes, and pouring new concrete, an upflush toilet makes the process much easier.

Instead of relying on gravity to drain, a macerating toilet features a heavy-duty pump that is activated by a float and switch. Once the lower portion of the tank fills up, the macerator/pump turns on, forcing waste up through a 2-inch drain.

Note: You will need a 3-inch vent to conform to most local plumbing codes.

Today’s upflush toilet units are more dependable and come with pumps that are powerful enough to send solid waste and wastewater to the required distance to your house’s drain system. 

It will take you roughly a day to install an upflush toilet. Get started by first purchasing a macerating unit, drawing a plan, and consulting with your local plumbing inspector to ensure the plumbing will meet code.

Tools Required to Install an Upflush Toilet

You only need four basic connections to install an upflush toilet:

If you’re not an ardent DIYer, get someone skilled in installing plumbing/venting systems.

Overall, you don’t need to drop a ceiling or dig up the floor! You don’t even require any custom equipment!

An experienced plumber can install an upflush toilet in just a few hours or complete a whole bathroom in just a day at a fraction of the cost of constructing a traditional bathroom.


  • Spade
  • Level
  • Wheelbarrow
  • Garden hose
  • Adjustable wrench
  • Screwdriver
  • Hammer
  • Bucket


  • Sand-mix hydraulic concrete
  • Iron support flange
  • 2×6 joists
  • Toilet mounting bolts
  • Discharge pipe
  • Float switch
  • Rubber flange
  • GFCI receptacle
  • Liquid soap
  • 3-inch PVC vent pipe
  • 2-inch PVC drainpipe
  • Subfloor
  • Backflow device
  • Subfloor fasteners
  • Wax ring
  • Access panel
  • Upflush toilet
  • Stop valve

Step by Step Procedure on How to Install an Upflush Toilet

STEP 1: Check Depth

Before you choose an upflush toilet model and begin the installation, determine what type of macerating toilet you’ll need based on the overall distance from the sewer line. An upflush toilet can only be useful if your bathroom is well below the sewer line (approximately 12 feet) or if the drain pipes must travel a long distance (as long as 150 feet) before linking with the main sewer line.

A macerating toilet is designed with a rotating blade that grinds solid waste before pumping it away. The units come with smaller discharge and drainpipes, and the flush cycle normally takes 15 to 18 seconds.

Some manufacturers combine the toilet and the macerating pump in one compact unit while others feature a stand-alone pump with connections to showers and tubs. So, choose what works best for your situation.

STEP 2: Make Base

Most macerating units are designed to fit between 2×6-inch joists. Make a base that allows the toilet to rest on a stable and fairly level surface. If possible, build a simple 2×2-inch wooden frame, mix and spew sand-mix hydraulic concrete, and carefully set the component in the concrete.

Be sure to level the base in both directions and allow the concrete to cure properly before proceeding.

STEP 3: Install Support Flange

The next step is to install the iron support flange to prepare the unit for the toilet. Ensure that the toilet mounting bolts are positioned correctly and are long enough for proper mounting of the toilet.

STEP 4: Install Pump

Next, assemble the float switch and install the discharge pipe. Carefully place the pump in the tank and mount the float switch. Test the pump to make sure it’s working before sealing the unit. To do that, simply attach a garden hose to a water supply and run it through the flange hole.

STEP 5: Discharge Extra Water

Now, connect the discharge to a drainpipe that discharges to a bucket or floor drain. Be sure to tape the temporary drainpipe joints since the pump is usually forceful. Plug the unit into a GFCI receptacle and slowly fill the tank with water. Once the water reaches the correct level, the pump should come on automatically and discharge water through the drain pipe.

STEP 6: Install Vent Pipe

Insert the rubber flange provided in the package and insert a 3-inch PVC vent pipe to the unit. To achieve a tight fit, use liquid soap to make the pipe slippery. Now, run the vent into the main stack, ensuring that the vent and drain are configured to code.

STEP 7: Install Backflow Device

Next, connect the discharge pipe to the unit’s backflow device to ensure that no wastewater flows back into the unit. (Confirm that the right end faces up – it’s usually marked on the pipe). Connect a 2-inch PVC drainpipe to the discharge unit and let it run all the way to the house’s drain system as per the code.

STEP 8: Connect Pipes

Connect the vent and drain pipes to the house’s drain system. Plug the macerating unit into a GFCI receptacle mounted within reach from the access panel and connect the supply line. Finish up by installing the subfloor and walls, taking care not to puncture the tank with long fasteners.

STEP 9: Install the Toilet

Next, finish the floor and walls and mount the access panel. Mount the toilet onto a wax ring and let the bowl rest on the macerating unit. Connect your new toilet to a cold water supply line through a stop valve.

STEP 10: Connect Other Features

Finally, connect additional plumbing fixtures—usually a sink or tub/shower—to the macerating unit. Make sure that the drainpipes for these fixtures flow down to the upflush unit.

This will not pose a problem for the sink since the drain for a macerating unit is usually 16 inches above the floor. You will, however, need to raise the tub so the drain line can flow down to the macerating unit.

Types of Connections Required on the Outside

You will need to make the following 4 connections on the outside of your upflush unit:

  • Connect the macerator/pump to the spigot of the horizontal outlet toilet 
  • Connect the toilet tank to the water supply 
  • Connect the macerator/pump to the small diameter discharge pipework 
  • Connect the macerator/pump to the electrical supply. 

You can also connect the discharge pipes from the bathroom sink, shower, and/or bath.

Adding a Sink and Shower to Your Macerating Pump for a Full Bathroom

You can add a half bathroom or go full out by adding a sink, shower, and bathtub to your macerating pump.

Once you connect the pump to the toilet, you can seamlessly add multiple fixtures to create a full bathroom out of nothing. Just be sure to get the right type of pump that can effectively push up all the waste.

Upflush Toilet Maintenance: How to Clean an Upflush Toilet

Proper cleaning ensures that your upflush toilet system remains in good working conditions without compromising your family’s health. Here are the steps you should take when cleaning your macerating toilet:

Step 1

First, turn off the power to your upflush toilet’s macerator. Depending on the manufacturer and model, you can find the macerator’s power switch somewhere on the box itself, mostly located directly behind the toilet unit.

Step 2

Next, pour 2-3 cups of non-acidic toilet bowl cleaner in the toilet bowl. Allow it to settle for at least 2-3 hours to allow the cleaner to break up any deposits and grime that has accumulated inside the macerator.

Step 3

Now, turn the macerator on to allow the toilet bowl cleaner and other loose unwanted debris and particles to drain from the macerator through the drain system. The toilet bowl cleaner will also clean the inside of the plumbing pipes.

Pros and Cons of Upflush Toilets

Upflushing toilets offer numerous benefits, including flexibility, portability, cost-saving, and water efficiency. However, they also come with some downsides, such as high price tags and noise levels. In this section, we outline the pros and cons of upflush toilets to help you make an informed choice.

Pros of Upflush Toilets

If you’re looking to add a new bathroom in your basement, renovate an old home to incorporate an extra bathroom, or just want to avoid coughing thousands of dollars on a new bathroom construction, then an upflush toilet might be the right answer for you.

Here are the outstanding benefits of upflush toilets:

#1: Upflush Toilets Save Money in the Long Run 

An upflush toilet costs just a fraction of what a full traditional toilet construction costs. Installing one can save you thousands of dollars you would spend buying different plumbing fixtures and hiring a plumber for days.

This makes upflush toilets a fantastic choice for budget-conscious homeowners who can’t justify spending half of their life savings constructing an extra toilet.

Another way upflush toilets save you money is that they remove the need for digging and breaking walls and floors in your home. That’s something that often requires professional help, and the costs can rise quickly depending on the plumbing design you currently have.

Moreover, macerating toilets tend to be very water efficient. Currently, most upflowing toilets consume up to 1.28 gallons, saving you money on water utility bills.

Most traditional toilets take up an upward of 1.6 gallons per flush, meaning that an upflush toilet could save up to 70% in water usage.

#2: Same Aesthetics as Regular Toilets

When it comes to the appearance, size, stability, and comfort of an upflush toilet, there’s really no difference between this system and the regular toilet you already have in your home.

While an upflush toilet incorporates a macerator system and pump unit, all other fixtures, including the toilet seat, bowl, and flushing buttons or handles look virtually the same.

#3: More Flexibility

For many homeowners, macerating toilets offer a higher level of flexibility that standard toilets can’t match. Because many regular toilet flushing systems utilize gravity, they don’t function for rooms below the sewer line, such as in the basement.

With a pump system included, upflush toilets are able to send waste upwards much easily. You’ll not even need to worry about where your plumbing systems or drainage networks are in the home.

That’s why macerating toilets also work great for attics and temporary situations where you don’t want to drill into the wall or floor or completely re-design your plumbing system.

#4: Highly Portable

On top of their flexibility, upflush toilets are highly portable, allowing you to move it around your home with ease.

Although this will depend on the specific model you install, many all-in-one upflush toilets on the market can be moved around easily by simply unscrewing a few bolts.

#5: Upflush Toilets Can attach to Other Sanitary Ware

A macerating toilet system allows you to attach other commonly used bathroom hardware such as sinks and showers and take advantage of the same drainage system provided they are compatible and installed correctly.

Note that there are specific design considerations you must take into account to achieve this, but it is relatively easy to accomplish.

#6: A Longer Lifespan

Upflush toilets are built to last just as long as traditional toilets. Well-known brands such as Liberty Pumps and SaniFlo Macerating toilets are known to flush up to 50k times before the mechanical components require any replacement.

It can be safe to say that macerating toilets can last as long as 10-15 years, if not longer. However, the specific lifespan of your upflush toilet will depend on how well you look after it through regular cleaning and maintenance.

#7: Minimal Maintenance

All upflush toilets come sealed and ready to operate. What’s more, they require very minimal maintenance for the entire life of the pump.

#8: You Can Add a Bathroom Anywhere

With a macerating toilet, you can add an extra bathroom anywhere in your home. An upflush toilet allows you to transform any odd closet or empty space into a functional guest bathroom. Even in the basement, a macerating toilet makes it simple and cost-effective to add a bathroom.

Upflush toilets even allow you to install a temporary bathroom in a home under renovation, a home with an elderly family member who may find it difficult get up or down stairs, or a home with more residents than usual.

#9: Boost the Value of Your Home

According to HouseLogic, creating an extra full bathroom in your home can increase its value by more than 20%. Unfortunately, constructing a full traditional bathroom can cost as much as $50,000.

By installing an Upflush toilet, you can save money and get a better ROI down the road. Moreover, you can install an upflush toilet by yourself and save even more money.

#10: Ample Warranty

Upflush toilets often include a 3-year manufacturer’s warranty.

Cons of Upflush Toilets

As mentioned earlier, upflush toilets come with their fair share of disadvantages, including:

#1: Noise

If you’re looking for a toilet fixture with a quieter flush, an upflush toilet may not be the best option for you. Most traditional, compact toilet units are less noisy since they don’t have the mechanism to churn the waste and make it ready for pumping.

Although macerating toilets still use similar steps in the flushing process, the extra grinding process can produce extra noise that may be uncomfortable for some users.

#2: High Price Tags

The upfront cost of upflush toilets is generally high, especially if you’re going with well-known brands such as SaniFlo. Most standard gravity-fed toilets will rarely cost you more than $600, but units with a macerating pump can cost an upward of $1000.

#3: Power Cuts

If you’re off the grid, or simply lack electricity due to a power cut, a macerating toilet may not work for you. The same applies to any hardware connected to the macerator’s drainage system.

Unless you have a portable generator, a macerating toilet is best suited for homes with a reliable source of electricity.

What an Upflush Toilet is Not

Many homeowners confuse an upflush toilet with a composting toilet. The confusion often arises because these two toilet designs are relatively new in the US.

While a composting toilet uses evaporation and decomposition to eliminate waste and provide composting products, an upflush toilet works like the traditional toilet you already know and love.

It just runs on a waste elimination system that’s engineered differently – shredding and grinding all solid materials like human waste and toilet paper before pumping it upwards through a narrow pipe.

The SANIFLO Advantage

Although there are multiple upflush toilet brands out there, none has the sophistication, history, performance, research budgets, or full product lineup of Saniflo. Some models even carry very respectable brand names, but very few are truly macerating pumps. Most models use old technologies and frame them as macerating toilets.

This is why many homeowners have stuck with Saniflow upflush toilets for years. Although you can find other brands offering macerating toilets at much cheaper prices, you won’t probably get the proven SFA macerating technology, elaborate product warranty, a responsive technical support team, and the proven knowledge that the industry leader provides.

Here are the most popular Saniflo Upflush Toilets to Consider:

Common Upflush Toilet Problems and their Solutions

 Upflush toilets are increasingly becoming common in homes with basements or minimal space to install traditional bathrooms. These innovative toilets allow you to eliminate waste when flushing from below the sewer line.

However, creating a macerating system that is powerful and quiet, yet compact for installation in tiny spaces presents a huge problem. Macerating pumps often block, fail, or break at some point, and you’ll need to learn a few tricks to solve such problems.

In this section, we help you identify common potential issues with upflush toilets and how to deal with them. Read on!

#1: My Macerating toilet keeps running and will not switch off

One of the most common problems with macerating pumps is that they occasionally fail to switch off. The pump can flush and keep flushing, even when the macerator is clear.

More often, diagnosing the source of this hitch is not easy. It could be triggered by one problem or a mixture of issues, including:

  • A blockage in the macerator or pump
  • A blockage in the waste pipe leading to the external drain system
  • Damage to the pump’s rubber membrane
  • A faulty microswitch

The Solution

  • A blockage in the macerator – Turn off the power to the pump at the mains supply and physical check if there is a blockage in the pump’s macerator unit. If so, clear it using a pair of thin-nosed pliers as you slowly turn the blade counter-clockwise.
  • A blockage in the pump – Check if cotton buds or other debris are blocking the impellers and remove them. To access the pump, lift the motor out o the unit and turn the unit upside down.
  • A blockage in the waste outlet pipe – Check if the return valve is blocked as this can return the waste as it hits the blockage. To clear this, use thin-nosed pliers to remove the lid of the upflush unit and clear any blockage in the return valve. Sometimes, the return valve can be faulty and will require replacement.
  • The microswitch is misfiring – A misfiring microswitch is another common problem with upflush toilets. Solid waste can get lodged between the switch and the tank floor, which causes the switch to think that the tank is full and needs flushing. In such a case, you will need to clear the tank manually and restart the pump.
  • Damaged rubber membrane – The unit’s rubber membrane can get damaged and cause endless flushing. The rubber membrane is the thin sheet of rubber that water presses upon to switch on the pump. Once it is damaged or loses its seal, waste water can enter the switch and cause it to fail. Fortunately, if your macerating toilet is still within its warranty period, the manufacturer should cover the cost of replacement.

#2: My Upflush toilet is vibrating violently

If the macerator/pump is making a horrible vibrating noise whenever you flush the toilet, then there could be a foreign object caught in the macerator blade. You can choose to get your hands dirty and fix the issue yourself or call in a service plumber.

The Solution

Turn off the power to the pump at the mains supply (Never remove the macerator lid unless the pump is turned off). Carefully remove the cover and check inside the pump’s macerator if there is any foreign object that tangles the blade. Use a pair of thin-blade pliers to remove the object as you slowly turn the blade counter-clockwise.

#3: My Macerator keeps starting randomly

If the pump keeps firing randomly at different times of the day or night, then there could be a problem with the microswitch. This issue could be caused by a fault with the rubber membrane that triggers the switch or there could be some waste lodged between the switch and the floor.

The Solution

  • Misfiring microswitch – If the problem is a misfiring microswitch, check if there is any foreign object between the switch and tank floor. This can cause the switch to think that the tank is full and trigger the flushing. Fix the issue by removing any excess waste near the microswitch and restart the pump.
  • The rubber membrane is damaged – If the rubber membrane wears out or loses its seal, waste water can enter the switch and cause it to malfunction. In such a situation, you will need to replace the rubber membrane and the switch.

#4: My Upflush toilet continually trips the electrics

If your upflush toilet system continually trips the electrics, it could be severely damaged and should be handled with great care. First, turn off the mains electricity supply and examine the pump for damage. In many cases, the motor seal is probably faulty. If the unit’s motor seal is damaged, the motor itself could be full of water and will definitely cause a short circuit in the pump’s electronics.

The Solution

Contact a qualified electrician to check the electrical connection.

#5: My Macerating toilet is leaking/foaming up

If your macerating toilet’s microswitch grows too old, it may not fire until the tank gets sufficiently full. Eventually, when the microswitch is activated, the spinning mechanism may cause wastewater to escape through the air vents.

The Solution

First, try replacing the rubber membrane that protects the microswitch. Usually, as the rubber ages, it becomes loose, requiring more and more pressure to activate the switch. But if the problem persists after replacing the rubber membrane, it may be necessary to replace the entire microswitch.

#6: My Upflush toilet smells terrible

If your pump has operated for a few years, it is important to give it a thorough cleaning. Follow the manufacturer’s instructions for cleaning the unit correctly.

The Solution

Use a high-quality upflush toilet descaler to clean the pump. Avoid general cleaning chemicals or bleach since they can damage pump components.

#7: My macerating toilet keeps blocking and backs up to the shower basin

If your upflush toilet frequently blocks and backs up to the shower basin, it’s likely that the internal unit or waste pipe is blocked. Waste pipe blockage often occurs when the outlet pipe was installed incorrectly. Typically, the waste pipe should be installed at 45 degrees to ensure that solid waste is thoroughly cleared from the pump and won’t flow back to the tank.

The Solution

First, try removing any blockage from the macerator or water tank. If it fails to work, then the blockage is probably in the waste pipe. You will need to call a certified plumber to inspect and clear the blockage. More importantly, ensure the pipes are installed at an angle of 45 degrees.

#8: My Macerator is running but it is not pumping out

This problem often arises when the waste pipe is frozen, especially in winter.

The Solution

First, switch off the macerator unit and try to remove some of the waste manually, especially if the waste threatens to overflow. Wrap some hot towels along the length of the waste pipe to help loosen up the frozen blockage and finally flush out the waste.

Upflush Toilets FAQs

How much does it cost to install an Upflush toilet?

While prices vary widely depending on your specific circumstances, the average cost to install a macerating toilet ranges between $210 and $320 (assuming you won’t be installing completely new plumbing systems- which can get much more expensive). The cost can run as high as $550 if you require a new plumbing network.

Does an Upflush toilet need a vent?

All plumbing fixtures must be properly vented. Your upflush toilet should vent into your house’s main vent stack, which usually extends from the main sewer line all through to the roof. The macerating tank features a vent connection on top to help you with that.

Can you put a toilet in the basement?

With traditional toilet systems, it is impractical to have a toilet in the basement as most models rely on gravity to eliminate waste. However, upflush toilets feature a powerful macerating pump to push up waste even if the toilet is positioned below the main sewer line.

How do I clean my Upflush toilet?

To clean your upflush toilet, pour 1-2.5 liters of non-acid Toilet Cleaner and Macerator Descaler into your toilet bowl. Switch on the macerator pump for a few seconds to enable the descaler to enter the macerator. Switch off the macerator again and allow the descaler to work for 2 hours. Finally, flush the toilet to get a sparkling clean toilet.

How long do Upflush toilets last?

On average, macerating toilets last about 10-15 years before any mechanical components need to be replaced.

Why does my Upflush toilet smell?

Bad smells can be triggered by a build-up of solid waste or limescale in the 2-3 inches of water that always remains in the macerating unit. To determine if it’s your upflush toilet that’s emitting the bad odor, flush the toilet or fill the basin with water and then unplug it.

In some cases, the smell can emerge from the tank itself, although it is often scent-sealed. Always choose upflush toilets that are EPA-friendly to minimize the chances of bad odor.

Final Words

Hopefully, this comprehensive guide has helped you understand how an upflush toilet works and given you some hints on what to do when things go awry. If you’re still wandering whether a macerating toilet is right for you, feel free to reach us via the comment box below. Whatever decision you make, always follow the correct building and plumbing codes.

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