What is plenum and PVC cable, and why is the plenum cable so much more expensive?
Plenum-rated cable has a special insulation that has low-smoke and low-flame characteristics. Plenum cable is mandated to be installed in any “air handling” space. For example, most large office buildings use the ceiling to return air to the AC unit. This qualifies the ceiling space and a plenum space, and all cable that go through that ceiling must be plenum rated. Please check with your building officials to see if you need plenum cable. Plenum cable costs more because the material required for the insulation is more expensive.
