Want to refinish your vinyl floor ?
Some vinyl flooring, especially vinyl sheets that were made several decades ago, could contain asbestos ... and asbestos is hazardous to health when the fibers are airborne. So, vinyl flooring containing asbestos should not be sanded as this may release harmful asbestos fibers into the air.
Laying a new flooring over vinyl floors
Laying a new flooring over an existing vinyl floor is a fairly common practice. If the existing floor is smooth, or can be smoothened easily, then a new floor can be laid directly on top of the existing floor.
Another approach is to use a 1/4 inch plywood over the existing floor to provide a smooth base, and then a new flooring is laid on the plywood.
This process will raise your floor considerably, and the new floor may not connect smoothly with the adjacent floors.