One of my favorite fabrics for white slipcovers is bull denim. What is bull denim? Basically, it’s blue jean fabric without the indigo. Instead of blue yarns woven with white the fabric is dyed all one color like white, natural or other solid color.
Bull denim is a medium to heavyweight cotton twill fabric that’s made with thick yarns. You might have seen bull denim labeled “laundered” or “washed”. That’s a good thing because those are types of finishes that make the denim feel supple, which is what you want when making a slipcover. This type of denim fabric is durable without being stiff, offers really good coverage and it wrinkles less than most canvas fabrics.
I prefer the substantial feel of 12 to 14 ounce white bull denim over the lighter 9 to 10 ounce especially when I need to cover an upholstered piece that is a medium to dark color. Be sure to buy a one yard piece to test shrinkage and coverage before you buy large quantities. Each weight and brand of bull denim differs from each other in shrinkage and performance.
Tip: if you find a cotton bull denim you really want but it’s labeled Dry Clean Only buy one yard and wash test it. That’s what I do. I machine wash it on warm and tumble dry on hot. Many times I find the fabric washes just fine and shrinks within reason for the type of projects I do.