Work out cable quantity estimate instantly with clear inputs, formula shown and shareable results.
Cable quantity is outlet count times average run length plus a wastage allowance for service loops, mis-pulls and termination slack — 10 to 15 percent is typical. Because cable comes in fixed 305 m boxes, the order rounds up, and short runs left at the end of a box are usually unusable, which the surplus figure makes visible.
Cable quantity
total metres = outlets x average run x (1 + wastage); boxes = ceil(total / box length)
Take the distance from the comms room to the nearest and furthest outlet, average them, and add allowance for vertical drops and cable-tray routing rather than straight lines.
So an outlet can be re-terminated after damage or moved a short distance. A couple of metres coiled above the ceiling saves a complete re-pull later.