Adding a new sprinkler head is a common modification undertaken to improve the uniformity of water distribution and ensure complete coverage across a landscape. This simple Do-It-Yourself project requires tapping into an existing zone’s lateral line and integrating a new emission device into the network. Following a sequential process ensures the structural integrity of the irrigation system is maintained and the new head functions optimally to enhance water delivery efficiency.
Planning and Gathering Supplies
Determine the optimal placement for the new sprinkler head to eliminate dry spots without causing wasteful overlap or overspray onto non-lawn areas. Map the head’s location to identify the nearest lateral line in the existing zone that can be accessed for the connection. After locating the pipe, shut off the water supply to the entire zone at the main valve to prevent flooding during the modification process.
Confirm the zone’s hydraulic capacity, specifically the gallons per minute (GPM) and pounds per square inch (PSI), to ensure the addition of one more head will not cause a significant pressure drop across the circuit. Once the location is finalized, gather the necessary materials. These include the new sprinkler head, a T-fitting compatible with the existing pipe diameter, a riser, and Teflon tape. Tools required are a shovel, a specialized PVC pipe cutter, PVC primer, and solvent cement.
Tapping the Main Irrigation Line
The first step involves excavating the area around the planned connection point to expose the existing lateral line, typically requiring a trench 12 to 18 inches deep. Once the pipe is accessible, clean the surface to remove any soil or debris that might interfere with cutting and bonding. Use a ratchet-style PVC cutter to make a clean, straight cut, removing a segment of pipe equal to the length of the T-fitting.
With the section removed, begin the chemical bonding process. Apply PVC primer to both the inside of the T-fitting ends and the outside of the exposed pipe ends. The primer softens the rigid plastic surface, allowing for better fusion with the cement. Immediately apply the solvent cement to the same surfaces, and quickly push the T-fitting onto both pipe ends with a slight twisting motion to distribute the cement evenly.
The cement chemically welds the fitting to the pipe, creating a permanent, watertight joint as the solvent evaporates. Hold the joint firmly in place for approximately 30 seconds to prevent the pipe from pushing the fitting off before the bond sets. If the existing pipe is too rigid to accept the T-fitting, incorporate a specialized component like a slip-fix coupling or a short, flexible pipe segment to bridge the gap and facilitate installation.
Connecting the Riser and Installing the Head
With the T-fitting bonded to the lateral line, connect the vertical pipe, known as the riser, which delivers water to the surface. Choose between a rigid PVC riser or a flexible swing joint assembly; the latter offers superior protection against damage from lawn equipment or ground settlement. Seal the threaded connection between the T-fitting and the riser using polytetrafluoroethylene (PTFE) tape, commonly known as Teflon tape.
Wrap the PTFE tape tightly around the male threads of the riser in a clockwise direction to prevent it from unraveling when screwed into the T-fitting. This tape acts as a thread sealant and lubricant, filling microscopic gaps in the threads to prevent water from escaping under pressure. Connect the riser to the T-fitting, and then attach the new sprinkler head to the top of the riser.
The final height adjustment requires positioning the sprinkler head’s body so its top surface sits flush with the finished grade of the lawn once the trench is backfilled. For rotor or spray heads, set the final orientation and coverage pattern before full operation. This involves manually adjusting the arc stops to define the desired spray pattern and using a small flat-head screwdriver to fine-tune the radius control screw, which alters the water stream distance.
Final System Testing and Cleanup
After the head is installed and adjusted, slowly restore the water supply to the zone to repressurize the system. This gradual introduction of pressure helps prevent water hammer, which could stress the newly cemented joints. Observe the entire system immediately for any visible leaks around the new T-fitting connection or the threaded joints of the riser and head.
Once the system is fully pressurized and leak-free, activate the zone to observe the water distribution pattern of the new head alongside existing heads. This confirms that the spray arc and distance adjustments are correctly set to achieve head-to-head coverage without creating excessively wet or dry areas. The new head should operate as an integrated part of the zone, ensuring uniform precipitation across the targeted area.
With satisfactory coverage confirmed, carefully backfill the trench, taking care not to disturb the newly installed piping or the sprinkler head itself. Compact the soil around the pipe and up to the head, ensuring the top of the sprinkler remains level and flush with the surrounding finished grade. Proper compaction minimizes the risk of the head sinking or shifting over time.