Probably the most popular size is 1/2” Poly Tubing, since this is the most commonly used size for drip systems.
The sprinkler pipe size from the water supply source to a sprinkler shall be not less than 3/4 of an inch (20 mm) in diameter. Threaded adapter fittings at the point where sprinklers are attached to the piping shall be not less than 1/2 of an inch (15 mm) in diameter.
If you choose to use PVC pipe for your irrigation laterals, make sure to use pipe that is at least 3/4" thick. 1/2" inch laterals clog very easily. If you choose to use fittings, most common PVC fitting types work fine.
The 1/2″ sizes of drip supply tubing are the most common sizes in use today, but there are also larger sizes produced and installed, although they are mainly used in commercial and agricultural installations.
The most used sizes are: 2-⅜”, 2-⅞”, 3-½” and 4-½”. The tubing joint length: is the length of tubing joint including the coupling and excluding the pin thread.
The most common size of main line drip tubing is also called 1/2" mainline drip tubing. Now, there are many sizes of 1/2" drip tubing and almost none of them actually measure 1/2". The most common size in drip irrigation is . 700, measuring .
A common rule that is followed for obstructions within 18 inches of the sprinkler deflector is the “three times rule”. This requires sprinklers to be positioned away from obstructions a minimum or three times the maximum dimension of the obstruction.
Nothing should be in that area between the bottom of the sprinkler heads and the imaginary horizontal plane parallel to the ceiling that is 18 inches below. This is done to allow an even and unobstructed spray pattern from the sprinklers when triggered to extinguish the fire.
You can operate 2 or 3 sprinklers at one time with 'Y's and extra hoses, depending on your water pressure. To run more than one sprinkler off the same faucet, attach a 'Y' to your faucet and run a hose to each sprinkler.
My recommendation is to bury sprinkler lines 8-12 inches. I usually try to keep a standard depth of 10" because it provides more safety if I need to do some type of ground work so I don't have to worry about hitting lines. A walk-behind rototiller generally won't go deeper than 8".
A big mistake that people make is putting the pipe trenches either too deep or too shallow. Pipe trenches for an in-ground sprinkler system need to be at least 7 inches underground and no more than 10 inches.
Specifically, “PEX or any other listed nonmetallic material can now be used in a standalone wet fire sprinkler system 'if the maximum static pressure from the water supply does not exceed 80 psi' – or a pressure release valve and an automatic means of pressure release is used when the pressure from the water supply is ...
The standard 1″ PVC pipe used for lawn sprinkler systems is rated to withstand 200 pounds per square inch (PSI). Comparable 1″ poly pipe is rated to withstand 100 PSI. In fact, to achieve the same pressure rating as PVC, the walls of poly would have to be twice as thick.
For spray heads, it is 30 psi, with an operating range of 15 to 30 psi. For drip lines, this is about 20 psi, with an operating range of 15 to 30 psi. Remember, flow rate and pressure are directly related to one another. If pressure is not well-controlled, irrigation efficiency will suffer.
Sprinkler heads must be a maximum of 12-15 feet apart, depending on the hazard rating of the space (it ranges from Light Hazard to Extra Hazard 1&2), and at least half that distance from the nearest walls (typically 7.5 feet away).
The “Four Times Rule” is really just an extension of the “three times rule” however it covers extended coverage sprinklers and the maximum clearance is 36 inches (0.9144 m).
5.4 (pendent and upright) and 10.3. 4.4 (sidewall), require 6 feet of clearance between heads. That minimum distance is measured from the center of each sprinkler head (or, “on center”).
The average system uses approximately 15-16 gallons per minute, per station.
Ordinary Hazard 1 and 2: Coverage area of 130 square feet per sprinkler head; 15-foot distance maximum between sprinklers. Extra Hazard 1 and 2: Coverage area of 90-130 square feet per sprinkler head, based on certain factors; 12-foot distance maximum between each sprinkler head.
For example, the capacity for 1/2 poly tubing is 200 feet (single run length) and 200 gallons per hour (flow rate). If you have a 1/2 tubing single run length of over 200 feet, you may have inconsistent water flow at your drip emitters due such factors as friction between the tubing walls and the water flow.