The phrase "heavy draperies" refers to curtains or window coverings that are made of thick, dense fabric. They are called "heavy" because they have weight to them and are often used to block out light and provide privacy. Full definition
Take advantage of natural light by opening or removing heavy draperies. (rismedia.com)
As he took his oath, they could be heard chanting «hey hey ho ho, Paladino's got to go» through the stone walls and heavy draperies of the hearing room. (wben.com)
Instead of hanging heavy draperies that camouflage views, home owners can add an extra insulation layer within the cellular structure of a sheer, light - filtering fabric, so that it looks attractive and also keeps out cold or heat. (realtormag.realtor.org)