Do you live in an area with high labor and overhead costs?
Different cost of living from region to region is the main reason why there is no hard “average” cost for installing a sprinkler system. If you live in the suburbs of Detroit where there are plenty of sprinkler contractors and business overhead is moderate, all else equal you will find a lower average bid than you will in Long Island where overhead is high. If you live in a high cost part of the country you could end up saving significantly more by installing yourself.
Do you live in a cold weather climate where you need deeper trenches for pipe?
In cold weather markets it is generally a good idea to bury pipes at least 12 inches deep to reduce the possibility of early or late season freeze (in any freezing market, prior to deep winter you should blow pipes out with compressed air or otherwise drain them to avoid freeze breaks in the pipe. For winterization instructions click here) and the deeper the trenches the more time you need to allow for trenching and cleaning. In many northern markets contractors avoid trenching altogether by “pulling” poly pipe through the ground with something called a “vibratory plow.” While you could theoretically rent one and pull poly pipe yourself, this is not a project for the novice. Options would be to pay a contractor to pull pipe or dig trenches for you, or dig the trenches yourself. For less than $200 a day most equipment supply stores will rent a “trencher”, which makes shorter work of digging trenches.
Do you have rocky, clay or “hardpan” soil that is difficult to dig?
The type of soil that lies below the surface will be a major factor in how long it takes to pull pipe or dig trenches for a sprinkler system. A trenching machine will have a tendency to hop or buck in rocky, clay or hardpan soil, and this could increase pretty dramatically the time and effort required to get the trenching done. Regardless of how you want to do it, you should grade the entire landscape to finished level before installing the sprinkler system. After the grading is complete one way that you can test how hard difficult trenching will be is to make sure the ground is moist (but not wet) and then use a shovel to dig the holes for your sprinkler manifolds. If it is impossible to dig even those holes, you can assume that even with a trencher digging trenches will be hard work, which may tip you in favor of hiring a contractor to do the trenching and then you do the rest.
Do you have several distinct small areas to water or do you have just a few large areas?
The size of the different areas in your yard makes a surprisingly big difference in how much automatic sprinklers cost. Perhaps it’s not intuitive, but it is typically costs much less to install sprinklers in a few large areas than it does to install sprinklers in many small areas, even if the total square feet of the large area is significantly more than it is for the small areas. This is because of two main factors: first, large areas generally require a lot less pipe and heads than small areas; and, second, several small areas can significantly drive up the number of zones that are required and this increases the cost of valves, wire, and sprinkler timers. So, as a general rule, the more small areas that you design into your landscape – especially if they have different watering requirements – the higher will be the cost of your installation.