## How do you size the drainage systems?

The sizing of drainage piping systems is based on fixture unit values. The fixture unit value takes into consideration the average rate of discharge, duration of use for a single operation and the interval between each operation of a plumbing fixture.

### What is the correct slope for a drain pipe?

¼ inch per foot

The ideal slope of any drain line is ¼ inch per foot of pipe. In other words, for every foot the pipe travels horizontally, it should be dropping ¼ inch vertically. Many drains either have too little slope or too much slope. That’s right, it is possible to have too much slope in your drain lines.

#### What are the four main plumbing systems?

They are:

- Single stack system.
- Partially vented single stack system.
- One-pipe system.
- Two-pipe system.

**What are the basic plumbing systems?**

Plumbing and Drainage Principles The main inlet system with water delivered by local municipality, borewells or a water harvesting unit. This water flows through various fixtures to different rooms for different purposes. Used and wastewater then gets collected into drains at various points across the home.

**How many toilets can you run on a 3 inch line?**

There is one answer. The International Plumbing Code requires 5 Drainage Fixture Units in a bathroom group. It’s good for 20 DFU’s or 4 bathroom groups.

## Can you put a 90 in a sewer line?

It’s fine to have a larger-radius (sweep) 90-degree bend at the base of a vertical drainage stack where the wastewater starts to travel horizontally. It’s also a good idea to have a sweep 90-degree fitting where a drain pipe pops out of a wall for a kitchen, vanity or laundry sink.

### How do you calculate the fall of a drain?

Drainage Gradients Falls

- FALL = GRADIENT X DISTANCE.
- Invert Levels.
- The level at the crown of the pipe = the invert level + internal diameter of the pipe + pipe wall thickness.
- Manholes can be manufactured from masonry or precast concrete.