01.06.09
Curtains
Curtains are often hung on the inside of a building’s window to block the travel of light, for instance at night to aid sleeping, or to stop light from escaping outside the building (stopping people outside from being able to see inside, often for privacy reasons). Curtains come in a variety of shapes, materials, sizes, colors and patterns, and they often have their own sections within department stores, while some shops are completely dedicated to selling curtains. Curtains are a form of window treatment, and complete the overall appearance of the house. Contents
Light control and insulation
Curtains can be made from varying thicknesses of fabric, each with a differing degree of light absorption and heat insulating qualities. Sheer curtains allow a majority of light to be transmitted through the fabric, with the fabric weave providing a basic level of UV protection while retaining maximum visibility through the curtain. Sheer curtains are sometimes referred to as privacy curtains in reference to their screening abilities; during the day most sheer fabrics will allow people inside the home to see the outside view whilst preventing people outside the home from seeing directly into the home. Due to the loose weave in sheer fabrics, these types of curtains offer very little in the way of heat insulation.
Uncoated fabrics provide the next level of heat insulation and light absorption. Uncoated fabrics consist of the vast majority of fabrics used in curtains, and are composed of a tightly woven fabric, most typically a cotton/polyester blend, which is mostly opaque when viewed in ambient light. Uncoated fabrics provide a reasonable level of heat insulation due to the tight weave of the fabric, however the fabric itself is typically not thick enough to completely absorb strong light sources. As a result, when curtains made from uncoated fabrics are closed in an attempt to block out direct sunlight, light will still be visible through the curtain.
Coated fabrics consist of a standard uncoated fabric with an opaque rubber backing applied to the rear of the fabric to provide improved light absorption. A fabric that has been through the coating process once is considered a 1 pass coated fabric, anecdotally referred to as dim-out because of the fabric’s ability to absorb approximately 50-70% of a direct light source. To improve the light absorption of a fabric it is possible to re-coat a fabric up to a maximum of 3 pass coated, which is considered sufficient to block out 100% of a direct light source, hence such fabrics are referred to as block out coated.
Maximum light absorption and heat insulation in a curtain is created through a lined curtain, which typically consists of an uncoated fabric at the front to provide the look and feel of the curtain, with a separate coated fabric attached at the rear to provide the insolating qualities. On some curtain rails/poles, there is pulley system for opening and closing called Corded curtain tracks.
