Shades control amount of light while draperies control air circulation. Light can still penetrate the room when shades are up and draperies are closed but air is trapped behind fabric. Fitted Roman shade covers the entire window area halting air circulation when shade is lowered. Using a white lining on the glass side will reflect light and heat back outside.
Restricting air circulation around a window is a requirement for maximum energy savings. A close fitting Roman Shade that is mounted inside the window opening will trap dead air against the glass and reduce heat loss or gain by as much as 25%. To maximize energy efficiency, mount shades as close to the glass as possible.