If you have a window that is longer then eight feet, you can always buy two rods that equal the width and connect them with connector screws and a center support.
The longest lengths we produce are 8'6" or 8' depending on the type of rod being used. For a longer setup you'd require two or more rods equaling the length needed with use of a Connector Screw accessory.
Connector screws can be found in our Accessories Section. Note the screw is for connecting purposes only and not a weight bearing structure. As well we generally recommend a bracket placed at the point of connection for support.