Plumbing 101: Pipes Used in Custom Homes

[vance]

In most states you can’t use a reducing bushing for drain lines. You need a bell that has nothing to catch on you can use 3” for a closet ring. Why put 4” to go into a 3” it will bottle neck and cause future problems.

[mattphillips]

I always wondered what pipes were for. Thanks.

[danielwalsh]

Sorry im lost is that a 4" going into the 3"??

[jadesmith]

The 4" vertical toilet pipe goes to your 3" horizontal pipe to your septic tank or sewer. The connection should be 45 deg and must be sloped towards a lower point. He forgets to mention the 4" rain pipe that goes to the 2" pipe that either goes in the ground or to a rain ditch which doesn't need to be sloped

[jadesmith]

You basically have dirty and clean water pipes. The dirty one needs a slope not to have your waste get stuck. Sometimes the 2 pipes become combined if the distance to the sewer is too long. The septic tank has an overflow to the sewer.