When you buy a hand-knotted rug, this means that a skilled weaver individually tied every knot, this creating a one-of-a-kind handmade rug. That is what makes hand-knotted rugs so special, and that is what makes them so much more expensive than all other types of area rugs. Depending on how many knots are in each square inch (50 to 160 knots per inch is typical, 400 per square inch is remarkable), it can take more than a year for one weaver to complete a 9x12 rug.