Water distributing system for plumbing

After considering the major sections of a piping system, such as the water supply main, the soil stack, and the house drain, we must then plan the several branches which will carry water to and from these systems. Not only must we be sure that we will have outlets where we need them, but also we have to be certain that adequate water at sufficient pressure will be fed to them.

Cold water usually passes directly from the supply main to the fixtures; hot water must, of course, pass through some heating device. In designing a piping layout, a list should be made of those fixtures which will need both hot and cold water pipes running to them, and those which will need only one of the two. Such a check list is given below:

Using both hot and cold water kitchen sink

  • Bathroom sink
  • Bathroom bathtub
  • Bathroom shower
  • Extra sinks and showers
  • Wash and laundry tubs
  • Washing machine

Using only cold water

  • Water closets
  • Fire sprinkler systems
  • Lawn sprinkler systems
  • Outside faucets and hose connections

If you live on a farm, there are several other water outlets needed, such as connections to barns, coops, or pens, and water troughs. But regardless of where you live, your plans must take into account the average daily consumption of those using the system, so that the necessary amount will be available. The table below computes this for you. These are average figures and may vary considerably in different situations.

Check list

In planning the location of your kitchen and bathroom installations, consider these points carefully:

Water consumption

  • For each member of family 35 gal. per day
  • For each cow 30 gal. per day
  • For each horse 15 gal. per day
  • For each hog 2 gal. per day
  • For each sheep 1 1/2 gal. per day
  • For each 100 chickens 3 gal. per day
  • For each sprinkler, 1/2" hose 200 gal. per hour
  • For each sprinkler, 3/4" hose 300 gal. per hour
  1. Can the newly installed pipes be run between existing partitions? If they can, well and good, because the finished job will look better. However, beware of weakening partitions. Rather than have this occur, run the pipe exposed and then box it in.
  2. Are you being economy-wise and placing the kitchen sink on the same wall that contains other plumbing? If you have two upstairs bathrooms, are you placing them back to back, or as close to each other as possible? Are they directly over the kitchen? Such an arrangement permits kitchen waste to drain off into the waste pipe or soil lines from the bathroom.
  3. Does your water-closet soil pipe run parallel to the floor joists wherever possible? If not, you will have to cut into the joists during installation, thereby weakening the building. If it is impossible to run the soil pipe between the floor beams, it is recommended that it be run along the ceiling below and then boxed in.
  4. Do the kitchen and bathroom have adequate window space? Windows provide important ventilation and light. A pleasant view through the kitchen window makes working there much less arduous.
  5. Can you place all kitchen and bathroom fixtures along one wall? If you can, you will save pipe, reduce the number of fittings, and have less trouble in making the installation.
  6. Have you planned to pitch your piping so that supply lines pitch downward toward fixtures and waste lines pitch downward away from fixtures? By taking advantage of gravity, this arrangement adds pressure at fixture openings and speeds the flow of waste. All piping, except traps, should have a pitch of 1/4" per foot.
  7. Do you know how the piping runs in both your supply and drainage systems? Where they meet at fixture openings? Have you kept wall and beam cutting to a minimum to prevent weakening the structure?
  8. Have you been careful not to run drain pipe from an ice-box containing food into your soil and waste lines? Since gases from soil and waste lines might contaminate food, drainage from food containers should be collected separately.
  9. Does your soil-pipe vent extend through the roof? Keep it away from shafts or chimneys as this permits odours to enter the house. Minimum health standards strongly recommend full-size vents.
  10. Have you chosen the piping best suited to your installation? Will it be the most economical in the long run? Read the sections on the different kinds of pipe before you make any purchases. Remember that a slightly higher initial expenditure for better pipe may save time-and money-consuming repairs in a few years.
  11. Does waste piping fall away or pitch sharply enough to guarantee that waste will drain without clogging the system? Does it bend smoothly and without any sharp, angular turns?
  12. Have you made an accurate sketch of your installation? Do you know what tools and materials you will need? Are you certain of your procedure? For these important steps, read the next section carefully.
  13. In your bathroom planning, have you considered that the soil stack and water closet require your largest connection and so should be installed as near to one another as is feasible?
  14. Have you considered the effects of a given pipe's weight on both the installation and the structure of the house? For example, cast iron enamelled fixtures weigh several hundred pounds, while the newer types made of pressed steel weigh much less; cast iron pipe is heavier than copper tubing, requires more support, and involves more fittings.


In the present discussion of the various parts of the house piping system, fixtures will be referred to continuously, but no specific information will be given about them. Those desiring detailed information on fixtures to be placed in a specific room should refer to a different page covering that room.

Plumbing basics

Bathroom fixtures
Bathroom floor plans
Bathtub installation
Installing lavatory
Water closet install

Cesspool / septic tanks

Fixture pipes
House drain
House sewer
Soil stack
Vent piping

Finishing touch

Heating a home


Dishwasher install
Garbage disposer install
Kitchen plans
Kitchen sink installation
Laundry install
Room plans
Work areas

Cast Iron

Plumbing layout
Pipe plan
Water distributing

Faucet repair
Pipe problems
Repair other
Toilet repair


Plumbing materials
Specialty tools

Water Supply

Hot water heaters
Running pipes
Service connection
Water meter
Water savings

Wells / pumps