Sprinkler Head Layout

One of the main tasks of designing an irrigation system is the sprinkler head layout. The sprinkler head layout consists of deciding what kind of sprinkler heads will be used and where exactly they will be placed. When I do a layout I place flags in the yard representing where each head will go.

I continue to mark out the sprinkler heads, using different color flags for each individual zone. For example, the front right spray zone may have blue flags at each spot where a spray heads will be placed, a side spray zone may have orange flags, and a back rotor zone would have red flags.

Keeping each zone its' own color will help you with the building of your sprinkler system so that you don't mix the wrong heads on a particular sprinkler zone.

When laying out your lawn sprinkler system remember to not mix rotors and spray heads as I mentioned in my previous article. Rotors and sprays put out water at a different rate so you'll want to keep them separated.

Rotor heads typically throw 30 feet and can be reduced slightly if needed. Sprays can throw from 4 feet to 18 feet depending on what type of nozzle you use. Rotors can usually be adjusted from about 25 degrees to 360 degrees radius. Spray nozzles come in either fixed or adjustable pattern radius. I try and stick with fixed nozzles (ie. 15 half, 10 quarter, 12 full ect...) because they have a better spray pattern and don't tend to get clogged like the adjustable pattern sprays.

Overall the most important factor when doing a lawn sprinkler head layout is to make sure that you have "head to head" coverage. What this means is that the water from one sprinkler head reaches the next sprinkler head in the yard. This will ensure even precipitation and "double coverage" which is essential to a proper lawn sprinkler design.

So remember when designing out your lawn sprinkler system to make sure that you don't mix rotors & sprays, you have double or "head to head" coverage, and use different color flags to represent the different zones.

The Difference between Rotor and Spray heads

Often when I am giving a bid or an estimate on a sprinkler system I get asked whether I will be using rotors or sprays. Not everyone asks this question, but those who've learned information about irrigation and lawn sprinklers tend to ask.

The answer that I give people is "we use a combination of rotors and sprays depending on the landscape." When I say a combination I don't mean that you mix rotors and sprays on the same zone, I mean that you will use rotors in the larger turf areas and sprays in the flower beds and smaller grass areas.

Rotors have a smaller precipitation rate than spray heads. That means that they take longer to get the same sized area wet and spray heads water an area quicker. Spray heads just pop up and don't rotate, while rotors have to turn to water the area that they are designed to water. This is why it is not a good idea to mix rotors and sprays; because you will either overwater or underwater a section of that zone.

Frequently with certain designs and curves of a landscape, a spray head may need to be added to a rotor zone. Sometimes it is just impractical to have to run a separate line just to add one spray head, so you break the "rule" and add one head. With sandy permeable soil, you can tend to get away with this with little bad effects, but with a denser soil I would not recommend it.

If you can space your heads 25 -35 feet apart then you should use rotor heads. Rotors have bigger water droplets, don't get clogged like sprays, and cover a larger area than sprays. Spray heads are good for areas where you can space heads 4' to 15' apart. Spray can work better with landscapes with a lot of curves, and will water an area quicker, but they will get clogged more often when using a well supply.

That's all for now. Have a happy 4th of July tomorrow!