Thermal curtains and blackout curtains filter and block light and air that can move through your windows and into your rooms. These curtains are generally heavy, insulated window coverings. Thermal curtains tend to be better at preventing the loss of heat in a room, and blackout curtains are better at blocking light.
Thermal curtains are created using heavy fabric and insulation. This two-layered window covering is an excellent means of preventing cold air from entering a room through a drafty window frame. Thermal curtains can be hung in any window that produces a draft. They can also be hung on door windows. These window coverings are most effective when they are pulled completely across a window frame.
Blackout curtains are created to block light. They can be made from layered fabric much like thermal curtains or from a single heavy, dense fabric such as felt. These curtains are available in a style which can be fitted inside the frame of a window. They are held in position with hook and loop tape, preventing any light from entering the space.
Blackout curtains are used in areas where additional light is an issue, such as photography film processing rooms. They are often used in bedrooms to prevent early daylight from disturbing the sleep of people who are sensitive to light or who work night shifts and must sleep during the day.