How To Vent A Toilet Without A Vent

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Ventless toilets have become a popular alternative to other types of toilets. They are often cheaper and more environmentally friendly, but they also come with a few disadvantages. This article will go over some of the ways you can vent your toilet without using vents.

What is a ventless toilet and how does it work?

Ventless toilets are just like regular ones, except there is no vent for the toilet to release the water vapor. Instead, they use a siphon action that pulls the water out of the toilet bowl into an underground waste pipe.

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This means you don't have to worry about clogs from air getting drawn down into your pipes and it reduces the need for water to be transported out of your home.

Why are ventless toilets bad?

While they are a good alternative, ventless toilets do have their problems. The biggest one is that there is no vent outside of the toilet itself. This means any gasses released when using it will not be able to escape into the atmosphere but will remain in your indoor environment where they can cause health problems and odors.

These issues may require you to buy an expensive venting system or get rid of your new toilet altogether if you plan on keeping it in any location other than a basement or garage. Lastly, if you live in an area with high-water tables, your bathroom might end up smelling like sewage and you might have trouble flushing your toilet if the waste pipe is too deep underground.

How to install a ventless toilet

Before starting, make sure to check with the manufacturer of your toilet to see if it is approved for use in your region.

You will also need a level surface that is at least 18 inches off the ground and has a drain hole nearby. You can build this table or buy one from a hardware store such as Lowes or Home Depot.

Step by Step Instructions:

The base can be made from wood, but make sure it is strong enough to support the weight of your toilet.

The easiest way to determine if it is too weak or strong enough is by placing your toilet on it and checking for any rocking motion. You will also need access to a drain hole for the waste pipe as well as PVC or ABS piping to connect the two.

If you are not able to make a solid connection between the two pipes, they may end up splitting over time and cause a huge mess when water begins leaking out of your toilet. You can use a 2-1/2″ ABS pipe inside the HDPE pipe to help increase its strength.

Step 1:Build the frame 

Build the frame for your table and make sure it is level before attaching your PVC piping. The length of this table will depend on how deep you want to bury your waste pipe, but make sure you have enough room for all parts.

If you are using wood or something lighter, such as plastic or aluminum, then I would suggest adding some extra bracing around the area where the pipes meet to ensure they don't become unlevel over time due to shifting ground and pressure from the surrounding soil.

Step 2: Dig the hole outside your house

Dig the hole outside your house for the waste pipe and temporarily attach a section of ABS pipe to it. Before attaching PVC to the ABS you will need to cover both with plastic mesh to prevent any moisture from getting in through small cracks.

This can be done with regular wire mesh that is wrapped around each piece several times or by cutting up a thick plastic bag and wrapping it around each one.

If you are using wood for your table, make sure the soil isn't too wet before digging, otherwise, it could weaken or split your table. The depth of this hole should be just deep enough so that when it rains, water does not start to pool at the surface. If this happens, then you will most likely get wet wood and begin to see puddles of wastewater.

Step 3: connect the hole to the PVC pipe

 After digging your hole, connect it to the PVC pipe that is coming from under your house using a T-shaped section. You can use a long piece of ABS piping to temporarily connect these two instead if needed, but make sure it can be easily removed later on so you don't have a giant wad of plastic sticking out of your backyard once everything has been installed.

The other end of the PVC should also come up through the ground somewhere around or near where your base will be placed for it to drain into the pipe when you flush.

Step 4: Mark where the hold should be

Once you have everything connected, place your toilet on the base and mark where the hole will be. You should also make sure that it is level before proceeding to the next step.

Step 5: Drill a small hole

Drill a small hole through each of the four corners of the toilet's base and use PVC or ABS cement to fasten a plastic mesh cap to each one. This is done by putting a little bit of glue into the hole, forcing in some mesh with pliers, then using more pliers to force all of it down as far as possible.

Important: Make sure there are no gaps or cracks anywhere along this pipe if you want it to drain properly (which you do). If there are leaks, then the water won't flow through it and will instead end up pooling around the base of your toilet. This could lead to mold growth as well as possibly slow corrosion of the metal components.

Step 6: Add a little extra cement

Once all of that is in place, you can add a little extra cement along the edge of where your PVC pipe meets with your ABS or HDPE main waste line and quickly push it down into the hole before it hardens too much.

Try to aim for a bottom depth closer to 5 feet than 4-5 inches since this will help prevent leakage over time by making sure there are no large holes or cracks at any point below ground level. You should also make sure that you have reconnected your PVC pipe under pressure before doing this.

Step 7: Wait Before Testing

If you are using regular soil to fill in around everything then wait a couple of days until everything has been filled with water from the rain before burying it completely and test how well it all drains by placing something like a bucket or trash can over one of the holes with its bottom edge resting against a straight section of waste pipe close to where it exits the ground.

Once there is water on top of it, dump out any excess and then wait anywhere from one minute to a full day or two before dumping out the contents. 

Important: If you notice puddles forming at the bottom of your hole outside of where water is supposed to be draining into it, then there is a problem and you should correct whatever issues are causing it.

The most common causes for this are too much soil being used around the base with large clumps that aren't fully saturated with water, as well as rocks/roots/mud getting mixed in around ground level and allowing air gaps where debris can get stuck on top of your waste pipe.

Take some time (probably 10 minutes) to check everything out thoroughly by running your finger along each part of where the waste pipe meets up with the soil and make sure that there are no spots where it is covered by anything but the soil you used to fill in around your waste pipe.

Tips for using your new ventless toilet

If you live in an area with a high water table or where the ground cannot be dug deep enough due to rocks or other obstacles, consider installing your HDPE pipe vertically instead of using the drain hole.

This can also be helpful if the surface level is lower than your house for whatever reason and gives you a tall pipe instead of one that runs along the surface.

If you are not able to find ABS or PVC piping at your local hardware store, a plastic drainage pipe should work just fine as long as it fits on both ends and is thick enough so that it does not split over time. Just make sure to cover each end completely with something like wire mesh beforehand to prevent any moisture from getting inside.

How much does a ventless toilet cost?

Here's a quick pricing guide for building your ventless toilet: HDPE pipe, ABS or PVC fittings, and cement can usually be purchased in bulk at a hardware store (or online) for between $20-$50.

Plastic drainage pipe is usually available in 10 or 20-foot lengths and can be purchased locally with prices varying wildly depending on geographic location. If you haven't already cut off the end caps, remember to account for that cost as well.

What about air admittance valves?

What is an air admittance valve anyways?

An air admittance valve or AAV is a mechanical device that allows air into the drainage system. An air admittance valve balances the air pressure and positive pressure causes air admittance valves to close so that gases from plumbing and sewer pipes do not escape into homes.

How do you install an air admittance valve?

So you have decided that an air admittance valve is the solution to your ventless toilet, you will need to have a tee sanitary connection pipe first. With the right sanitary tee pipe, you will be able to install air admittance valves with ease no matter what brand you have bought.

Before checking out which air admittance valves your local plumbing shops sell, it is important to check out your local plumbing codes as they differ from the international plumbing code. If air admittance valves are permitted, determine what air admittance valve size you need. Then, determine what air admittance valve is compatible with the vent pipe material you have.

Measure out your drain pipes and make sure that the air admittance valve is located at least 4″ above the horizontal drain and 6″ above insulation materials along your drain line. An air admittance valve should be installed properly within 15 degrees of vertical vent pipe. Connect the left and right parts of the tee sanitarian waste pipe and install air admittance valve. Position the disconnected part of the sanitary tee pipe to the ceiling. Connect the vent with Teflon tape and then install the air admittance valves.

Building a ventless toilet for less than $100

If you are on a tight budget, or just want to see how low you can take it, here is one example of steps that could be taken to build your ventless toilet for around $40-$75 plus the cost of an old bucket and some plumbing pipe fittings.

This would also work if you don't have sufficient space outside the house to make proper use of one of these commercially available units by using a rigid drainage pipe instead of a pre-formed PVC pipe. This will allow you to have taller walls and/or waterproof everything better than with traditional PVC waste pipes. Just remember to make sure there is enough room within the house (and yourself) to deal with the smell of your waste.

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This design also will not work if you have a water table that is constantly being pumped out or if the ground cannot be dug deep enough, since it requires an opening into the soil to drain wastewater outside. However, with proper sealing, you may be able to correct this issue by using a rigid pipe and then just cutting off any excess plastic above grade level once everything is sealed inside.

Potential problems with your toilet

Before we conclude this article, keep in mind that there are some common problems that you should be aware of when it comes to your toilet.

Knowing that these problems exist is a proactive way of anticipating any problems and knowing how to fix them if they happen.

For example, understanding what toilet gurgling means, how to identify the problem and actually fix it is quite crucial.

Final thoughts on how to vent a toilet without a vent

In conclusion,  ventless toilets can be a great way to save money and reduce water usage when compared to other types of toilets. They are also much better for the environment than using a full flush toilet with some sort of septic or sewer system attached, which is important if you live in an area that naturally does not have easy access to proper sewage disposal facilities.

However, ventless toilets may not be right for everyone or every situation, depending on how many people will need to use them and where you want to locate your toilet inside your house. They do have a unique smell that most people grow accustomed to after time but having said that venting properly will help minimize sewer gases and smells from the inside and out.

Jim Spencer

Jim Spencer

Jim has been in the construction business for over 12 years with plenty of experience working on client projects, from start to finish. From kitchens to bathrooms and backyard spaces, he writes on a wide variety of topics surrounding home improvement.

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