Canvas drop cloths are just about the easiest canvas product to obtain, in dimensions that make them appealing for artists looking for wide widths and long yardage. It pays to choose carefully, however, because many fabric drop cloths fail to meet the standards most artists consider essential for permanent art.
Hardware-grade drop cloths are about the same weight as lighter grade cotton duck sold in art supply stores, with a more porous weave, so they are better suited to smaller works. Also, the weave may not be well balanced between warp and weft compared to artist’s canvas, so the fabric may be stronger in one direction than the other, and may exhibit unpredictable shrinkage.
Most of the time, the best way to use this affordable canvas is to size and prime it heavily to promote planar stability and to avoid paint striking through openings in the weave. A heavy-bodied acrylic gesso may be enough on its own, but when adapting hardware-grade products for artistic painting, applying a separate sizing before priming can yield better results. A utility-grade white PVA glue, diluted to a brushable consistency, can be applied to stretched canvas as a sizing to stiffen fabric, close a porous weave, and prepare it to receive an architectural primer.
Canvas that is too lightweight to stretch can be mounted to hardboard or another rigid substrate to make canvas-covered panels.