Traditional layout using 5x6 blocks or 30 shirts with sashing (framing) and different color "cornerstone" with one with additional outer border. My preferred color is a light grey. Grey is a great blending color that looks great with most t-shirt colors. It also doesn't show the lint and fuzz that a darker color (navy, black, etc) does. I use the same grey color as the backing fabric.
Some of the quilting pattern selections stitched on t-shirt quilts - simple and open designs are best.
Swirls quilting design Allover Meander Deb's Swirls String Bauhaus
Variable Layouts can be totally random or in a column format with or without sashing strips. You will need more shirts to obtain a decent sized quilt with blocks cut in a variety of sizes. However if the majority of your shirt designs are the same size and over 10 inches, then not as many shirts will be required. When the designs vary dramatically in size from shirt to shirt, more shirts are needed. Keep in mind that fronts and backs of shirts may be used to help make up the difference - completed quilt size always depends on graphic size and quantity of shirts provided. The quilts below ended up as lap size rather than bed size-- with the far right quilts utilizing sashing strips and an outer border to help increase finished size.
Don't have enough shirts for a larger quilt, pieced blocks can be added (black for the left and brightly colored squares on the right represent your shirts) The 2 color hourglass block is made to increase the size of your quilt -- the solid squares represent the t-shirts.
Bedding and Comforter Sizes
Standard and older mattress
depth is 9-12" New mattresses run 14-16" in
depth. If the quilt is to be used for a bed, I highly
recommend measuring the width and length to determine how
many shirts will be needed - or adding additional borders to
make large enough. There will be some shrinkage during
the quilting process as well as when the quilt has been
washed and dried.