Enter the dimensions for your custom cornice in inches between 18" - 141" wide. When ordering, make sure there is additional space available on both sides of window to accommodate cornice thickness. The ordered width will be the outside measurement. Eltham, Arundel & Bamboo cornices inside width will be 2" narrower than ordered width due to thickness of cornice; Arundel Crown inside width will be 7" narrower than ordered width due to crown on cornice. Measure to ensure cornice will have enough depth to clear any undertreatment or moldings.
Plan to mount your cornice approximately 1-1⁄2" above the window opening, or window treatment.