"Canopy grade" white polytarps, on the other hand, have a weave of 12' x 14' (3.6 m x 4.3 m) or 14' x 14' (4.3 m x 4.3 m).Increasingly, white polytarp is used to construct mainsails, jibs, and mizzens, while the lightweight polytarp materials are reserved for making spinnakers.