What Are Plumbing Risers?

In plumbing, the term "riser" refers to the device that connects the lateral line in a sprinkler system to the sprinkler head itself. Essentially, a riser gives the water that flows in the sprinkler supply line a place to exit. Understanding more about risers and their application will help you install and maintain them.

Risers are a type of plumbing fitting. They connect on one end to the water supply line, and on the other end, to the sprinkler body that feeds your lawn. Risers have male pipe threads on either side of the fitting that screw into the base of the lateral supply line and the bottom of the sprinkler body. This design makes risers exceedingly simple to install and maintain. It also keeps their cost down. In general, a riser costs about $2 at most home improvement stores. One riser is needed for each sprinkler.

Risers are generally made out of plastic, although brass versions are available in some hardware stores. Plastic risers come in two forms: cutoff and fixed. Cutoff risers are built in sections that have a small, smooth ring at the tip of each section. This smooth part is designed to be snapped off or cut off with a hacksaw. This is useful for creating a custom-size riser for oddly shaped installations. Fixed risers have a smooth pipe with threads only at the tips. These types of risers come in set sizes and can not be modified.

Installing a riser is as simple as turning a light bulb. When sprinkler lines are laid out, they include a fitting called a riser adapter. These adapters have a hole pointed straight up that is used to connect the riser to the sprinkler. Insert one end of the riser into the hole on the adapter and turn it clockwise until tight. You do not need to use Teflon tape in most cases. Grab the riser with pliers and turn an additional quarter-turn to finish tightening the riser in to place.

Risers can break, so it's important to check them once every few years to make sure water isn't leaking from the connection. Frozen water can burst risers, and they can be crushed by being run over with a car or lawnmower. To inspect a riser, unscrew the sprinkler head by turning it counterclockwise until it pulls free from the riser. Grab the riser with pliers and turn counterclockwise until the riser pulls out of the supply line. Check the riser for signs of damage or cracks, and replace it with a new one if there is a problem.