What is cat 5 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 this ceiling as a plenum ceiling, and all the cables that go through that ceiling must be plenum rated. Please check with your building officials to see if you need plenum cable. The reason why it costs so much more is because the material required for the insulation must meet the standards for plenum cables while also meeting the standards for category 5. This material is relatively expensive.
