How to Install a Toilet Drain

Believe it or not, but it’s actually possible to install a toilet drain on your own. Even better, you don’t need a significant amount of DIY experience. You will simply need to be able to follow directions very carefully. Learning how to install a toilet drain is fairly straightforward, but there are still a number of elements to the project that must be kept in mind.

Getting Started

You’re going to get started by making your drain and vent systems are working correctly. You will also want to check local building codes since these requirements can vary from one building to the next. Failing to install the toilet drain properly can result in costly, even dangerous mistakes. This includes a sewer gas leak.

After you’ve figured out where to seat the toilet, you’ll need to look for the simplest route that will end with installing the toilet drain properly. You will need to keep to the minimum slope for your pipe, and you will also need to make sure things are ventilated properly.

Toilet And Drain Pipe Locations

Ready to get started? Here are the basic steps for installing your toilet drain:

• Make sure you have a comprehensive understanding of both building codes and permit requirements. These codes/requirements determine not only the size of your drain pipe but also the size of your vent. You may have to make an appointment for an inspection later on.
• Find your main plumbing stack, which is located in the basement or crawlspace. Figure out where it goes through your home, and then figure out where the exit is on the roof. Not only should you look for where your large waste drain pipes are running, but you will also want to figure out which pipes you can use for venting. Finally, figure out your access point for the drain pipes, main stacks, and vent pipes connecting to your toilet.
• Make plans for the possibility of opening walls and removing floors. With an integrated trap, you can prepare for direct drain connections with minimum bends.
• Give yourself enough room for installing your sanitary tee, which connects to your main stack or combo fitting to connect with your horizontal drain. Make sure you also have a clear understanding of your building code, in terms of finding limits on toilet drain pipe length.

At this point, you’re ready to get started with installing the actual pipes.

Installing Your Pipes

Time to get the pipes installed!

• Cutting your pipes, you will want to assemble them without doing any actual gluing. This will ensure you’ve cut the proper lengths, and that they are going to fit.
• Ensure the stack/current drain has firm support above and below where you plan to make your connection. Support braces are sometimes needed. Now, you’ll want to cut your existing pipe, before taking out a length equal to the length of your sanitary tee/combo fitting.
• Do you have play in your current pipes to insert new fitting? If so, apply pipe cleaner and pipe glue (one and then the other) to your flange and your fitting. Inserting your fitting, you will need to twist it firmly into your flange. If you can’t move your stack/drain pipes, purchase a no-hub flexible coupling. Cut away additional lengths of your current pipe, making sure it is equal to the length of your coupling. After gluing your additional length of pipe into the upstream flange of your fitting. Next, slide your coupling onto your upstream existing pipe. Glue your fitting into position on your downstream pipe. Finally, you will slide your coupling over your joint, and begin tightening.
• At this point, you’re almost done! You will need to start gluing your remaining pieces of pipes and fittings into the proper position. You will work your way from your main drain pipe to the location of your toilet. Every four feet or so, you’re going to want to provide support for your pipes with pipe straps. The final bend, which can be found upwards and under the toilet. Make sure this bend has proper support, as well. It should also reach high enough to allow you install your toilet flange correctly.

These are the simple steps that will take you through this project. As we mentioned before, this is a fairly straightforward project. You don’t need to have a significant amount of DIY experience for something like this, but a basic understanding of plumbing can prove to be useful. Use this article to give you an absolute understanding of what needs to be done. You may also want to consult other informational resources, which can serve to break things down even further.

In the end, if you don’t think this is the right project for you, remember that most plumbers provide services that include work such as this.

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