It's fairly easy to get flummoxed, as pvc ball valve there are so many different plastic pipes. Not long ago I installed a somewhat special plastic pipe to vent my daughter's new high-efficiency boiler. It is made from polypropylene and can withstand much higher temperatures than standard PVC that most plumbers might use.It's very important to realize that there are lots of different plastic pipes that you might use, and the chemistry of them is quite complex. I'm just going to stick with the most basic ones you might run into or might be required to use by your local inspectors.I used PVC for decades, and it’s fantastic material. As you might expect, it comes in different sizes.
The most common sizes you’d use around your home would be 1½-, 2wo-, three- and four-inch. The 1½-inch size is used to capture water that might flow out of a kitchen sink, a bathroom vanity or a tub. The two-inch pipe is commonly used to drain a shower stall or washing machine, and it may be used as a vertical stack for a kitchen sink.A three-inch pipe is what’s used in homes to pipe toilets. The four-inch pipe is used as the building drain under floors or in crawlspaces to transport all the wastewater from a home out to the septic tank or sewer.
The four-inch pipe may also be used in a home if it’s capturing two or more bathrooms. Plumbers and inspectors use pipe-sizing tables to tell them what size pipe needs to be used where.The wall thickness of the pipes is different as well as the inner structure of the PVC. Many years ago, all I would use would be schedule 40 PVC pipe for house plumbing. You can now buy a schedule 40 PVC pipe that has the same dimensions as traditional PVC but is lighter weight. It's called cellular PVC.
It passes most codes and may work for you in your new room addition bathroom. Be sure to clear this first with your local plumbing inspector.Give SDR-35 PVC a good look for the outside drain lines you want to install. It’s a strong pipe, and the sidewalls are thinner than the schedule 40 pipe. I’ve used the SDR-35 pipe for decades with fantastic success. The last house I built for my family had over 120 feet of six-inch SDR-35 pipe that connected my house to the city sewer.
