From a theoretical point of view, there is really no limit to how wide a Roman Quilt Shade can be. However, from a practical standpoint, shades wider than 72" are more difficult to fabricate and operate. Also, shipping long components can be prohibitively expensive. We recommend that wider windows be treated with multiple shades. For example, a 140" wide window may have two shades; each slightly less than 70". One with cord pulls on the right. One with the pulls on the left. A single top treatment or valance can cover the entire window. The result - a cohesive, attractive window treatment that is easier to operate.
Large windows may take a bit of planning, but they are really simple to treat when you think outside the box.