Typically this is only relevant when a curtain panel turns a corner. Velcro attachment generally uses an outside hang (a path around the OUTSIDE of support columns) while tracking attachment generally uses an inside hang.
Keep this theme in mind. Your curtains need to be wider than your actual exposure so that you can seal the sides. In addition, we are working with textiles so there is a bit of variance in what you will receive (usually plus or minus 1" per 10ft of width). The heights, we generally get spot on. Width Adjustment: We recommend adding 3" per panel + 1" per 10ft of width. Height Adjustment: No adjustment for tracking / 2" taller than your exposed opening for Velcro Attachment.
You want to minimize the number of panels whenever possible. Introduce a new panel only where you need a doorway, have an obstruction, or are trying to create a certain swagging configuration. Velcro™ attachment panels can be as wide as you like. Also, mosquito netting curtains using tracking attachment can get too wide and difficult to pull around a track. Try to keep tracking attachment curtain panels less than 30 feet wide (8 meters).