ask This Old House
About 10 years ago, we had an irrigation system installed. Now, some sprinkler heads barely pop up above the lawn surface. How can I raise them?
—DON BAKER, MEMPHIS, TN
TOH LANDSCAPE CONTRACTOR JENN NAWADA: Raising the level of a sprinkler head isn’t difficult, if you’re up for a little digging.
But before you do that, measure how much the top of each sprinkler head needs to be raised to bring it up flush with the ground.
For each head that has sunk by ½ inch or more, get a cutoff riser with tapered male threads on both ends. (Heads sunk by less than half an inch should still function just fine.) These risers, sold online and at home centers, are molded with up to six ½-inch-long, male-threaded fittings arranged end to end. You just cut off the fittings you need, thread them into the T fitting on the irrigation system’s supply line, and then screw the sprinkler head onto the riser.
Start by shutting off the valve for the irrigation system’s water supply. Then carefully dig around each of the sunken heads with a shovel or trowel until you expose the irrigation line and the T fitting to which the head is connected.
Clear the soil around one head with a stiff brush and a damp rag, and take off the head with a few counter clockwise twists. Screw the appropriate riser into the T and then screw the head, by hand, tightly into the riser. There’s no need to seal these connections with plumber’s tape or pipe dope; the tapered threads do that.
Do the same with the other sunken heads, but don’t fill around them yet. Turn the supply valve back on and inspect the exposed fittings for leaks. If there are any, a simple retightening should stop
