A curtain (sometimes known as a drape, mainly in the United States) is a piece of cloth intended to block or obscure light, or drafts, or water in the case of a shower curtain. A curtain is additionally the movable screen or drape in a theatre that separates the stage from the auditorium or that serves as a backdrop.
Curtains hung over a doorway are known as portières. Curtains are often hung on the inside of a building's windows to block the passage 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). In this application, they're additionally known as "draperies". Curtains come in a variety of shapes, materials, sizes, colours and patterns, and they often have their own sections within department stores, while a few shops are completely dedicated to selling curtains.
Curtains vary according to cleanability, ultraviolet light deterioration, oil and dust retention, noise absorption, fire resistance, and life span! Curtains might be moved by hand, with cords, by press-button pads or remote-controlled computers. They are held out of the way of the window by means of curtain tie-backs. Measuring curtain sizes needed for each window varies greatly according to the type of curtain needed, window size, and type and weight of curtain.
Curtains are a form of window treatment, and complete the overall appearance of the house. Window treatment helps control the ambiance and flow of natural light into the room. The effect of drapery or curtains is best seen in daylight, and with proper indoor light positioning, can look attractive even at night.
From evidence found in excavation sites at Olynthus, Pompeii and Herculaneum, portieres appear to have been used as room dividers in classic antiquity. Mosaics from the second to sixth century show curtains suspended from rods spanning arches.
Light control and insulation
Curtains are manufactured from a variety of thick fabrics, each with a differing degree of light absorption and heat insulating qualities. For maximum temperature control, the curtain gap to the window should be small, with minimum convection draughts below or above the curtain. Various architectural structures around the curtain can minimise these air drafts, but usually they're just used for decoration and make rooms feel more cozy.
A sheer or net curtain is one that's made from translucent fabric, such as a loosely woven polyester voile or a cotton lace. 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 outward through the curtain. Sheer curtains are at times referred to as "privacy curtains" in reference to their screening abilities; throughout the day most sheer fabrics will allow people inside the home to see the outside view while preventing people outside the home from seeing directly into the home. Due to the loose weave in sheer fabrics, these types of curtains offer quite little in the way of heat insulation.
Uncoated fabrics provide the next level of heat insulation and light absorption. Uncoated fabrics constitute 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. Notwithstanding 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. To create a coated fabric, a liquefied rubber polymer is applied in a single coat to an uncoated fabric and subsequently fused dry by means of a heated roller, in much the same way that a laser printer applies toner to a sheet of paper before fusing it dry. A fabric that has been through the coating process once is considered a "1-pass-coated" fabric, anecdotally referred to as "dim-out" or "blackout" 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 one hundred percent of a direct light source, hence such fabrics are referred to as "blockout-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 insulative qualities. The coated fabric is typically referred to as a lining, which simply refers to a coated fabric that doesn't have any particular colour or pattern.
Curtains might be held back with tie-backs (a loop of cloth, cord, etc., placed around a curtain to hold it open to one side; typically passed through a ring on a hook attached to the wall, and fastened with a knot, button, or velcro; often adorned with tassels) or might be closed and opened with sticks called draw-pulls (rods made of plastic, wood, or metal that can be twisted and/or pulled) or curtain rods which are attached either to the runner or to the first hook. On a few curtain rails/poles, there's a pulley system for opening and closing called a "corded curtain track". The knobs at the end of these cords are called cord pulls or "acorns". A roll-down or drop-down curtain has its fabric rolled around the curtain rod and is lowered down from above by a separate device (such as pictured at right) or by pulling the fabric itself, with curtains using the latter mechanism being called pull-down curtains.
A curtain hook stopper is a device used to stop the curtain from falling off the end of the curtain rail.
With the increase in single family homes throughout the last century, the curtain and drapery industries have witnessed simultaneous growth in the demand for their products. Commercial interests additionally grew throughout that time as a large number of companies tried to supply institutions, hotels, etc. Pre-made curtain are sold in "panels" in stores, typically of around 7 feet in length. Cubicle Curtains are a popular choice in hospitals and medical facilities for privacy.
- Flat panel curtains are simple and versatile: to make them, pieces of fabric are hemmed on all four edges and the final rectangular or square piece is hung from curtains poles with clip-on rings or something similar. If pleated, the look is strongly influenced by the fullness of the pleats.
- Tab top curtains are made with narrow straps, that loop or tie at the top edge and hung from the curtain pole. This curtain style is often designed as two stationary panels at the sides of a window.
- Grommet curtains are hung by threading the curtain pole through a hole in the top of the fabric. This can be either a cut-out hole with the edges finished by a row of stitching or it could use a grommet to prevent fraying.
- Sash curtains are used to cover the lower sash of the windows.
- Rod pocket curtains have a channel sewn into the top of the fabric. A curtain rod is passed through the channel to hang.
- Thermal or Blackout curtains use quite tightly woven fabric, usually in multiple layers. They not only block out the light, but can additionally serve as an acoustic or thermal dampener.