LET’S ASSUME THAT YOUR COMPANY gets a contract with a homeowner whose property encompasses the size of two football fields, and, in addition to regular lawn maintenance, that homeowner wants you to install an irrigation system. You and your employees are all very happy—after all, this is a big job.

But here’s the problem: You’ve never installed an irrigation system before. All of those valves, sprinklers and wires—it’s enough to make your head explode. You don’t want to walk away from the job, so you do the next best thing and hire a subcontractor to come and do it for you.

Although many contractors are quite reliable, it turns out that the sub you hired has a serious issue with punctuality. His crew doesn’t show up when it’s supposed to, and your new client is left tapping his foot impatiently waiting for the work to get done. Half the day rolls by, and your sub still hasn’t appeared. You try to explain the situation to this new client and reschedule the installation, but he doesn’t want to hear it. The contract is cancelled and you’re left counting the dollars you lost while you wasted all that time.

Safe to say, no contractor wants to be put in such a position. If you want to build a strong relationship with your clients, then it’s worth looking into making the installation yourself. It saves you the aggravation of having to rely on subs who may or may not be competent, and it shows your clients what a true ‘service oriented’ company is all about. By adding irrigation to your menu of services, you not only bring in an additional revenue source to your company, you can schedule installs at your convenience and not have to work around your sub’s schedule. There’s a great deal of innovations and time-saving techniques out in the world of irrigation. Manufacturers are offering more efficient products, making it easier and easier for contractors. It’s only a matter of taking advantage of them.

The know-how

So now that you’ve decided to get into irrigation, where do you start? First, you’ll want to learn how to make an installation. Go to a local irrigation supply company and ask to talk to the owner or manager. They’ll walk you through the entire installation process free of charge, and although you won’t grasp all of it at one time, at least you’re on your way. But what’s in it for them? It’s about building relationships. Just like you, they too are looking for new customers. If they can help you, and you start to do more irrigation installations, repairs, retrofits, etc., you will continue to buy from that supply company. They should have a loyal customer for years to come. Just about every wholesale irrigation supply store offers classes and training in irrigation. “We have 18 training classes scheduled for the next month,” says Wayne Wheeler, operations manager at Automatic Irrigation Supply Company, Fishers, Indiana.

“These classes teach our customers the profitable way to install systems. For new guys in this business, that knowledge should be on the top of the list.” In addition, many irrigation manufacturers offer classes to help educate contractors about their new products, new techniques and more efficient ways of installing systems. T

he Irrigation Association has also scheduled courses to those interested in expanding their irrigation knowledge. These courses cover an array of topics, from diagnosing wire problems to sprinkler scheduling to understanding pumps, controls and wells. It’s a great opportunity to learn more about what’s out there, both for new contractors and seasoned contractors who’ve been in the irrigation business for some time and may not be privy to the more recent technological developments. You’ll want to do some self-educating as well. Most municipalities require that some sort of backflow prevention device be installed. Start by learning from your local water purveyors what the backflow prevention requirements are in your area. When it comes to backflow prevention, different towns and regions have different permit processes. From there, you can determine what kind of backflow device you’ll need. What is a backflow? Why and how is it used? Simply put, a backflow device is a mechanical assembly of sophisticated check valves. It allows public water to flow onto a property but will not allow that water, once it has entered the property, to flow back so as not to contaminate public water. “A common mistake irrigators make when installing a backflow device is that they miscalculate the water pressure. A lot of guys get into trouble by assuming that they’ll have the same water pressure and flow rate for every single jobsite,” says Wheeler. “That’s a huge problem. You might end up with a system that doesn’t work, and you’ll have to go back and dig the yard up to add zones, which is a huge mess.”

Installation tips

Before you begin installing an irrigation system, you should sketch it out beforehand. This might take up extra time, but it will help you divide the system into zones. At the same time, you can come up with a material take-off so you’ll know how to quote the job. Once you’ve put the design on paper and checked it carefully, you’re ready to begin the installation. Some contractors will mark off the property to show where they will lay the PVC pipes or tubing. Others will use small marking flags to indicate where they will put the sprinkler heads. A number of contractors, especially if relatively new at this, will lay out the pipe on the ground, cut the ‘Ts’ and put the risers and sprinkler heads on, making sure it all fits.

They then will dig the trench and drop the whole unit in. The pipe can be laid either by trenching, digging by hand, or using a pipe puller. Trenching is a practical choice for areas that require pipe to be buried 12 to 18 inches, or in rough terrain and on smaller jobs. Some contractors consider pipe pullers to be far more efficient. “If the conditions are right, nothing beats pipe pullers,” says Jeffrey Knight, education manager for Ewing Irrigation Products, Phoenix, Arizona. This machine knifes through the ground and pulls the pipe behind it, so it cuts through the grass as opposed to trenching it.

“Pipe pulling is also a lot quicker for the contractor,” adds Knight. Once the pipe has been laid, you’re ready to install the sprinkler heads. If you’ve done your homework correctly, i.e., drawing it on paper first, all you should need to do is make sure you have the proper spacing between the heads. It is important to note that if you’re working with PVC and you cut the pipe to put in a ‘T’ for the sprinkler, make certain you bond the pipe properly. These steps must be taken with considerable patience when connecting the pipes. “You’ve got to let the primer set for a while,” says Jim Lewis, owner of Lewis Landscape Services, Tigard, Oregon. “Make sure the bonding materials have dried or the pipes will end up exploding when you turn the system on.” Knight recommends taping the can of solvent and primer together to save time. “The standard way to solventweld fittings and pipe is to apply primer and then the solvent. It’s a two-step process, so tape both cans together for easier access.” Now you can install the electronic valves. If you’re going to install the valves underground, they should always be put in a valve box. Again, if you need help the first few times around, talk to your irrigation supply store.

Always run a performance test on the system before you backfill any trenches. If there are any leaks or faults in the system, you’ll want to know before you have to dig the pipes back out. “You need to make sure it can hold water,” says Lewis. “If you skip this step, sometimes you won’t know that there are leaks in the system for a very long time.”

Irrigation innovations

Recent developments in technology have boosted irrigation to the next level. Manufacturers are continually putting out new products made principally with the contractor in mind. One of the areas of innovation that has been focused on in the irrigation industry is preassembly. It used to be that you had to assemble all irrigation elements, such as saddles, swing joints and valves, valves boxes, etc. Preassembled products save time and are easier to install. “Our preassembled valves can save contractors up to 44% in labor,” says Stuart Eyring, president of Hydro-Rain, an irrigation manufacturer in North Salt Lake, Utah. “We identified that we could put our adaptors in the valves so the contractor doesn’t have to do it. This gets rid of all of the cutting, measuring and gluing time and makes it quite easy to put together.”

Other manufacturers, such as Olson Irrigation Systems, Santee, California, and DFW Plastics, Saginaw, Texas, offer pre-plumbed irrigation valve boxes. They include valves and manifolds preassembled in a heavy-duty valve box. Drip lines are also seeing some advancement. Traditionally, drip lines have come in a coil. It typically took two people working together to lay the drip line out. One person would have to unroll the coil while the other had to hold onto the other end to keep it from snapping back into place. Today, drip lines can come with a special resin that dramatically increases their flexibility, allowing you to unroll them and lay them flat. The resin will keep the drip line flat so that it doesn’t snap back to its coiled state. Done this way, drip line installation becomes a one-man job.

Another innovation, a new brand of pipe called Blu-Lock from Hydro-Rain, allows the contractor to install a system relatively quickly and easily. Rather than gluing the pipes together with primer and cement, as is the traditional approach, Blu-Lock involves a plug-and-play process that allows you to simply slide the fittings directly into the pipe.

A Direct Bury series of wire connectors is offered by Rain Bird. These connectors include a wire strip indicator to mark exactly where the wire needs to be spliced.

“Say you haven’t been in the business for long. You might not know where to splice the wire. These indicators are basically a gauge which will make the splicing process that much easier for the newer contractor,” says Brian Mueller, senior product manager for Rain Bird, Tucson, Arizona. There are valve boxes on the market that feature built-in knockouts on the sides. These halfmoon shaped holes can be hit with a hammer so the sides are easily knocked out. This saves you the hassle of having to cut the box open yourself in order to wrap the manifold.

“One of the major trends today is towards wireless. Wireless rain sensors and moisture sensing devices allow irrigation systems to self-regulate their watering schedules according to the number of inches of rain on the ground and the amount of moisture in the soil,” says Mueller. “These devices send messages to and from the controller using radio frequencies. Traditional sensors can require 20 to 50 feet of wire, which can be costly. So wireless is a pretty logical alternative.”

A time to look ahead

In the last decade, tremendous strides have been made by manufacturers to reduce the amount of labor involved in installing an irrigation system. Preassembled pipe, valve boxes with valves and manifolds installed, wireless sensors— these are all byproducts of a much greater trend. Industrially—and more important, culturally—technology is moving more and more in the direction of efficiency. And as technology continues to move forward, so will the number of timesaving products introduced. This in turn will allow your company to complete a project more quickly, leaving you more time to take on new clients.

“In the recession that we’re in right now, material costs aren’t getting any lower,” says Eyring. “Contractors are going to need to look at new ways to generate revenue. We think the next frontier is in labor reduction costs, and that all comes down to speed and ease of installation.” “We look for ‘pain points’—points we can address to help the contractor,” says Mueller. “Because when we listen to what contractors have to say, we ask ourselves: ‘What can we do to make their lives easier?’”

ce your clients see that you’re capable of handling the irrigation, they’ll be more inclined to keep you as their go-to company for all their landscaping needs. And now you can advertise your irrigation services to your other clients. In a time when homeowners are looking to pinch pennies because of this massive economic downfall, forging those company-client relationships is more crucial than ever.

The conclusion of World War II marked the introduction of new technologies to private industry that were developed for the war effort. One that would certainly revolutionize the residential/commercial marker of the irrigation industry was thermoplastic pipe.

Born in the 1940s, plastic irrigation pipe really hit stride in the `60s, replacing galvanized steel, copper water tube, asbestos-cement and cast-iron pipe, all used in early residential/commercial irrigation systems. Because of its excellent corrosive resistance, light weight, high strength-to-weight ratio, durability and resiliency, more than 100,000 miles of PVC pipe is installed each year in North America.

Although some of these early materials are not as mainstream in today’s residential/commercial irrigation market, contractors are periodically confronted with their presence on an older site. It is helpful to understand the properties and performance of each.

Steel Pipe

Galvanized steel pipe is almost impossible to distinguish from wrought-iron pipe. Nevertheless, wherever you find steel pipe, you’ll find corrosion and chemical deposits that can accumulate and ultimately restrict flow. As the pipe ages, the condition worsens, dramatically affecting the performance and coverage of an irrigation system.

Designers estimate that in 15 years of operation, the flow capacity in steel pipe will be diminished by as much as 50 percent. In addition, rust and scale flaking can clog irrigation nozzles, and this condition too worsens with time. As a result, maintenance problems can recur if tapping into steel pipe at the supply source, and should be considered in the design and installation of sprinkler systems.

Cast-Iron Pipe

Historically, cast-iron pipe has been used for city water mains, although asbestos-cement pipe is giving it a good run. Although cast-iron piping rusts, it does not affect the performance of the pipe, rather it reduces its flow capacity. Designers estimate that in 18 years of operation, the flow capacity of cast iron pipe is diminished by as much as 50 percent. Here, too, there is a concern with rust clogging sprinkler orifices, particularly after any kind of maintenance or repair is performed.

Installation techniques for cast-iron pipe are critical to its proper specification, as the installation depth determines the recommended maximum pressure that should be applied. Cast-iron pipe should be fully supported by the trench bottom because it is extremely brittle, and backfill should be free of rocks and debris.

Asbestos-Cement Pipe

Asbestos-cement pipe is light weight and strong, and is completely free of rust and corrosion. Besides the two obvious materials, asbestos-cement pipe is also comprised of silica. Being nonmetallic, it will not conduct electricity and resists electrolysis and galvanic action.

As with cast-iron pipe, installation of asbestos-cement pipe is important because of its extreme brittle character. The trench and the backfill material must be meticulously uniform and free of debris, particularly rocks, to avoid pipe damage. Concrete thrust blocks are required at all fittings, angles and stubs, so that internal water pressures can’t pry fittings from the pipe.

Copper Water Tubing

Copper tubing is made for an abundance of purposes, but for the irrigation industry, copper water tubing is the appropriate product. Many plumbing codes require the use of copper in irrigation piping systems, and some designers still prefer copper water tubing for risers in shrub areas, as it won’t rust and quickly tarnishes, thus blending with the plant material.

There are three types of copper water tube — K,L and M. Type K is commonly used for 2-inch or less water services, like the piping connecting the city water main and yard meters, because it has the thickest wall. Type M, the thinnest-walled copper water tubing, is generally used in turf irrigation systems. All three are manufactured in rigid, straight lengths, but types K and L are also available in soft-annealed.

Although the working pressure of copper water tubing can handle most water pressures encountered in residential/commercial irrigation systems, the working pressures of normal soldered fitting joints are well below that of the tube and should be addressed at the design and installation levels.

Thermoplastic Pipe and Standards

Plastic pipe tends to be the product of choice in the residential/commercial irrigation industry for several reasons. It is relatively inexpensive, strong and durable, light weight and easy to work with, and is resistant to corrosion, rust or rot. Possibly the only advantage that metal pipe seems to have over plastic pipe is its strength, although for practical purposes, much of this strength is wasted by the lesser demands of most residential/commercial irrigation systems.

Creep and fatigue are phenomena that, through poor design or installation techniques, will damage a plastic irrigation piping system. Creep occurs when water pressure in the pipe exceeds the pressure rating. This stretching of the pipe thins the walls and, over time, can cause failure. Continual pressure surges, or water hammer, can create fatigue in pipes and fittings, which too can lead to piping system failure.

Pressure ratings, determined by the hydrostatic design stress, size and wall thickness of the pipe, represent the estimated maximum pressure that water can exert in the pipe with a “high degree of certainty” that failure will not occur. The pressure rating of plastic pipe is not the safe working pressure to which the pipe can be subjected over time.

Thermoplastic pipe for irrigation purposes is available in three product lines — SDR-PR, PVC and PE pipe. Nomenclature visible at regular intervals along pipe sections identify specifications needed to select the appropriate material at the distributor or in the field. The piping is coded as follows: letters on the pipe identify the kind of material used, and the four digits that follow indicate the type and grade of material (the first two digits), and the hydrostatic design stress in units of 100 psi (the last two digits).

Because of the range of pressure ratings for schedule wall plastic pipe, Standard Dimension Ratio – Pressure Rated (SDR-PR) pipe was developed and has become the mainstay of the residential/commercial irrigation industry. Each series of wall thickness is based on a “standard dimension ratio” — the ratio of pipe diameter to wall thickness.

The variety in types and grades of plastic pipe make industry standards significant. These standards serve to identify each kind of plastic pipe; dimensions; workmanship; sustained pressure; burst pressure; and more.

Poly Vinyl Chloride Pipe

Without question, poly vinyl chloride (PVC) is the most durable thermoplastic pipe made, due to its strength and its resistance to chemicals. Residential/commercial irrigation systems now often are exclusively PVC, however in some regions of the U.S., designers and contractors use asbestos-cement for larger pressure mainlines, and polyethylene (PE) for sub-mains and laterals.

Generally, when PVC is used for irrigation system piping, SDR-PR pipe is preferred, because of the uniform pressure ratings for all pipe sizes and because pressure ratings for SDR-PR are higher than those for schedule pipe in the larger sizes. There are standards for schedule 40, 80 and 120 PVC pipe.

Poly Ethylene Pipe

Poly ethylene pipe is a lower strength piping material than PVC and therefore is more prone to creep and fatigue over time. Consequently, PE has lower pressure ratings. Insert type fittings that aren’t solvent welded create more friction in the system and can require more labor to install. Special care should be exercised during installation.

Because it is so flexible, PE pipe tends to slither in the trench, which can affect sprinkler placement and alignment during installation. This flexibility also makes it more difficult to use drain valves to prevent freeze damage. An air compressor is usually required for winterization.

Poly ethylene is available in low-density (Type I), medium-density (Type II) and high-density (types III and IV) classifications. Types I and II are the most flexible and available in longer coils, making the pipe easier to lay using fewer fittings in long runs.

Poly ethylene pipe is made in two styles in both schedule-wall and SDR-PR wall pipe, SDR-PR being almost the exclusive product for residential/commercial irrigation systems. With some PE pipe, the inside diameter can be the constant, control dimension because of the use of internal insert fittings. The outside diameter of the wall increases in thickness to handle greater pressures. The second style uses the outside diameter for all sizes and the inside thickness varies.

Preferences in the use of PE and other pipe material are often found regionally and even locally. Rarely will you see anything but PVC systems in the Southwest, while you might see more PE pipe in the Rocky Mountain region and the East. Regardless, with the variety and abundance of piping materials available to the contractor, more efficient, durable residential/commercial irrigation systems are attainable.

The revolution in irrigation system piping material that has occurred over the last 50 years has essentially created the irrigation contractor and the residential/commercial irrigation market. The hydraulics of water transportation has become more precise, and properly designed irrigation systems perform better and last longer. Selecting the right material for your system’s framework ensures a lasting and effective system.