PVC Couplings

Standard PVC couplings (Slip, Threaded, and Reducing) are all appropriate for underground use, as long as they are installed properly. Use schedule 40 or schedule 80 PVC pipes and fittings, as these are rated for pressure and durability. PVC cement will also help create a lasting connection and a leak-proof seal.

When installing PVC couplings in a sprinkler system, it’s best to let the PVC cement dry for at least 2 hours before turning the water back on. Cool or damp weather can slow curing, and larger pipes usually need more time. For the safest result, check the cure time listed on your PVC cement can.

Most PVC couplings cannot be removed and reused once they have been glued in place. PVC cement works by softening and bonding the pipe and fitting together, so the coupling becomes a permanent part of the pipe. If you need to fix or change that section, the usual solution is to cut out the old coupling and install a new one.

The difference between Schedule 40 and Schedule 80 PVC couplings lies primarily in the thickness of the pipe walls and their pressure ratings. Schedule 80 PVC has thicker walls than Schedule 40 and provides greater resistance to pressure and physical damage. This also means that Schedule 80 PVC has a higher pressure rating.