Blockout fabrics eliminate heat and light from entering a building. They give complete privacy and are by far the most effective fabric in reducing heat gain to a space.
These fabrics are often used in rooms where the majority of outside light is desired to be blocked out such as bedrooms, theaters and officers especially where visual monitors or screens are to be viewed. These fabrics with the combination of linings have an added advantage of dampening sound and increasing audio fidelity.
Unlike screen and sheer fabrics, blockout fabrics promote a strong solid appearance to a space. A combination of both blockout and screen/sheer furnishings can be used to achieve light and openness during the day while complete privacy and darkness during at night.