Can you put a 90 on a sewer line without compromising the flow?

Answer 1

I assume you are talking about the line inside the house. If there is a section availible, a saddle clamp can be used to tap into the line. This consists of a patch that looks like a a section of pipe cut in half lenghwise. It is held on with 2 U-bolts. A hole is cut in the pipe and the saddle is clamped in place and connected to as you would any connection. You can tap into the top of the existing drain so the drain can be kept in use. above answer good but might be not quite the answer your looking for. simply put a sweep 90 {as opposed to a right angle} might slow the flow slightly but not enough to make a difference. I've installed a lot of sewer pipe.

These answers are both wrong... In drainage the only time you can use a 90 is when you go from horizontal piping to vertical piping and on the drop from a toilet you can use a 90 but you cannot use a 90 to go from vertical to horizontal... and making turns it is proper practice to use a wye and a 45 to create 90 degrees...and put a cleanout cap on the remaining side of the wye