Direct Burial & Outdoor Cable 101

Written by: Tektel Team

When running cables outside, installers turn to direct burial or outdoor cables. These types of cables are designed to withstand nature’s elements. 

Indoor cables are covered with a PVC jacket, which lacks UV protection and may deteriorate, whereas direct burial and outdoor cables are built for more extreme conditions,cables designed for outdoor use in cold climates are rated PE, and have a Polyethylene jacket. A PE jacket is made of a semi-crystalline thermoplastic material, which can withstand temperatures as low as -40C.

Direct burial cables are designed to be buried under the dirt with no need for a conduit. A conduit is a plastic or metal tub that protects the cable from outdoor elements,these are three different types of direct burial cables. The difference between them lies in the internal material used to construct them:

1.Gel-filled Unshielded Ethernet cable is filled with waterproof gel inside the cable. This gel oozes into the cracks & crevices that keep the internal wires coated, & prevent water from getting through to them & damaging the cable.

2.Water Proof Tape Unshielded Ethernet cable has a waterproof tape that covers the internal wiring, & protects the cable from water and moisture.

3.Water Proof Tape Shielded Ethernet cable has internal wires wrapped with PET tape, which is made of a material similar to polyester. Mylar tape is then applied around the PET tape to add shielding to the cables.

Some direct burial cables also feature a special built-in armor for rodent protection, to prevent rodents from chewing through the cables once they are buried in the ground. Direct burial cables are dramatically stiffer than indoor cables, since they are typically built with splines inside to reinforce their center to prevent them from getting crushed.

The types of cables available in outdoor rated or direct burial include Ethernet, coaxial & speaker wires. An outdoor / direct burial Ethernet cable can be used to run interned connection between structures, for example. An outdoor / direct burial speaker wire may be used to place speakers outside, avoiding exposed wires from source to speakers, amongst other uses. An outdoor / direct burial coaxial cable may be used to run external surveillance systems, closed circuit TV and more.