A window with an arched top is a common variation on the basic rectangular shape. If your windows have arched tops, you can still use basic roller blinds to cover them, simply hanging the blinds from the top of the rectangular area of window. A half-circle of window should remain visible at the top. This window treatment solution is best for tall windows and upper stories, where leaving the upper part of the window open doesn't cut down on your privacy. If you prefer to cover the upper arch as well, pair your roller blinds with a fan-style shade, placed at the top of the window.
Besides arched windows, another fairly popular alternative window shape is the rounded or oval design. If you have a porthole-like round window, you can still use a simple roller blind to regulate visibility easily. However, the design of your standard roller blind won't let you see the rounded effect when the blind is drawn down. Instead, you can opt for a special blind, designed for your window shape. Depending on the design, the blind may not operate exactly like a standard roller mechanism; it may draw to one side instead of up and down, or collapse into the middle instead of at the top.
You can select among a wider selection of roller blinds if your window can be broken down into rectangular or square elements, as in the case with arch-topped windows or the tall, narrow windows that commonly flank doors. Instead of plain white or beige blinds, you can opt for blinds with patterned fabrics. The look is ideal for contemporary decor, combining the clean, crisp lines of a blind with eye-catching prints.
Custom-made blinds may prove to be your best option if your window is a highly unusual shape, such as a multisided geometric form, or in the case of conservatory-style windows, if the window extends from the wall up along the ceiling. An additional advantage of customized blinds is that you can select the color, material and even pattern that best suit your space. Whereas standard blinds are typically used together with curtains or a valance, custom-made blinds may serve alone as window dressing.