Awning

An awning is a secondary covering attached to the exterior wall of a building. It is typically composed of canvas woven of acrylic, cotton or polyester yarn, or vinyl laminated to polyester fabric that is stretched tightly over a light structure of aluminum, iron or steel or possibly wood. The configuration of this structure is something of a truss, space frame or planar frame. Awnings are also often constructed of aluminum understucture with aluminum sheeting. These aluminum awnings are often used when a fabric awning is not a practical application where snow load as well as wind loads may be a factor.

The location of an awning on a building may be above a window, a door, or above the area along a sidewalk. With the addition of columns an awning becomes a canopy, which is able to extend further from a building, as in the case of an entrance to a hotel. Restaurants often use awnings broad enough to cover substantial outdoor area for outdoor dining, parties, or reception. In commercial buildings, an awning is often painted with information as to the name, business, and address, thus acting as a sign or billboard as well as providing shade, breaking steep winds, and protecting from rain or snow. In areas with wintry weather, most awnings do not have to be taken down at the end of the summer - they can remain retracted against the building all winter long, or be designed and built for those conditions.

History

Awnings were first used by the ancient Egyptian and Syrian civilizations. They are described as "woven mats" that shaded market stalls and homes. A Roman poet Lucretius, in 50 BC, said "Linen-awning, stretched, over mighty theatres, gives forth at times, a cracking roar, when much 'tis beaten about, betwixt the poles and cross-beams".

North America

Awnings became common during the first half of the 19th century. At that time they consisted of timber or cast iron posts set along the sidewalk edge and linked by a front cross bar. To lend support to larger installations, angled rafters linked the front cross bar to the building facade. The upper end of the canvas was connected to the facade with nails, with grommets and hooks, or by lacing the canvas to a head rod bolted to the facade. The other (projecting) end of the canvas was draped over, or laced to, a front bar with the edge often hanging down to form a valance. On ornate examples, metal posts were adorned with filigree and the tops decorated with spear ends, balls or other embellishments. On overcast days or when rain did not threaten, the covering was often rolled up against the building facade; during the winter months proper maintenance called for the removal and storage of awnings. Photographs from the mid-1800s often show the bare framework, suggesting that the covering was extended only when necessary. Canvas duck was the predominant awning fabric. A strong, closely woven cotton cloth used for centuries to make tents and sails.

Awnings became a common feature in the years after the Civil War. Iron plumbing pipe, which was quickly adapted for awning frames, became widely available and affordable as a result of mid-century industrialization. It was a natural material for awning frames, easily bent and threaded together to make a range of different shapes and sizes. At the same time the advent of the steamship forced canvas mills and sail makers to search for new markets. An awning industry developed offering an array of frame and fabric options adaptable to both storefronts and windows.

The National Park Service, US Department of the Interior, has published a fifteen page report: [http://www.nps.gov/history/hps/tps/briefs/brief44.htm "#44 Preservation Brief - The Use of Awnings on Historic Buildings - Repair, Replacement, & New Design"] . It was written in April 2005 by Chad Randl, an architectural historian.

Operable awnings

In the second half of the 19th century, manufactured operable awnings grew in popularity. Previously, most awnings had fixed frames-the primary way to retract the covering was to roll it up the rafters by hand. Operable systems for both storefront and window awnings had extension arms that were hinged where they joined the facade. The arms were lowered to project the awning or raised to retract the awning using simple rope and pulley arrangements. Because the canvas remained attached to the framework, retractable awnings allowed a more flexible approach to shading-shopkeepers and owners could incrementally adjust the amount of awning coverage depending upon the weather conditions. When the sun came out from behind clouds, the awning could be deployed with ease. In case of sudden storms, owners could quickly retract the awning against the building wall where it was protected from wind gusts.

But the early operable awnings had their own drawbacks. When retracted, the coverings on early operable awnings bunched up against the building facade where it was still partially exposed to inclement weather. (In fact, deterioration was often accelerated as moisture pooled in the fabric folds.) Also, the retracted fabric often obscured a portion of the window or door opening and unless it was folded carefully, presented an unkempt appearance. Modern materials and designs have eliminated these issues, and are also known as retractable awnings.

Benefits

Retractable awnings let owners control the weather on their own terms. When passing showers threaten, or when the sun gets hot, they unroll the awning for near-instant protection and shade. Lab test measurements show that it can be as much as 20 degrees cooler under an awning’s canopy. Because awnings prevent the sun from shining through windows and sliding glass doors, they can keep temperatures inside cooler as well, which saves on air-conditioning costs. They can help prevent carpets and furniture from fading in sunlight. Awnings also provide a sheltered place for children and pets to play, shielded from direct sun.

Some of today’s awnings also offer accessories that can greatly increase the versatility and usefulness owners get from their decks or patios. A screen room add-on can easily turn an awning into a virtually bug-free outdoor room, side screening cuts down on wind and mist coming under the sides of awnings, and patio lights let people enjoy their decks evenings and nights.

Types

Today’s awnings come in two basic types: Manually-operated models which are opened by hand and motorized models which operate by electricity. Each offers its own advantages. Benefits include low-cost affordability, easy adaptability to almost any deck or patio, and support arms that can be angled back against the house or set vertically on the deck or patio floor. These arms provide extra support and stability which some owners prefer in windy areas, and increase the awning’s versatility by making the attachment of certain accessories available.

Motorized awnings have no vertical supports. Instead, they have retracting lateral arms, creating an unobstructed shaded area. These awnings are operated by an electric motor, generally hidden inside the roller bar of the awning. The arms open and close the awning at the touch of a wall-mounted switch. Motorized awnings are the ultimate in convenience, with classic simplicity and beauty.

Modern awnings may be constructed with covers of various types of fabrics, aluminum, corrugated fiberglass, corrugated polycarbonate or other materials. High winds can cause damage to an extended awning, and newer designs incorporate a wind sensor for automatic retraction in certain conditions.

Wind Tolerance and Construction

Modern awnings are rated for wind tolerance based on width, length, number of supporting arms, and material. Modern awning design incorporates urethane compression joints, steel support structures, and wind sensors. Such designs are currently in use at the White House, Grand Central Station, and The Kremlin.

Aluminum Awnings

Aluminum awnings have long been popular in residential applications throughout the world. They are available in many colors and are usually painted with a baked-on enamel paint. Among the many benefits of these awnings are cooler temperatures inside the home, shade for your patio, extending the life of you furniture and window treatments. Possibly the most beneficial feature of the awnings are the fact that the have a usable life of well over 40 years.

Retractable awnings

Retractable Awnings are now becoming very popular with homeowners in the United States. They have been popular in Europe for many years, due to higher energy costs and lack of air conditioning. Retractable Awnings can include the following types:

Lateral Arm Awnings

These are a modern version of the old storefront crank-up awnings of the last century. Tension arms and a roller bar are supported by a torsion bar. The torsion bar fits into wall or soffit brackets that spread the load to the width of the wall. Hand-cranked awnings are still available, but motorized awnings are now most common. The motor is inside the roller tube. Many motors now have a built-in receiver and are operated by remote control.

Lateral arm awnings are also known as deck or patio awnings, as they can extend as far ast 18 feet and be as long as 30 feet or more - thus covering a large outdoor space.

ide or Drop Arm Awnings

Commonly used to shade a window, with a roller tube at the top, spring-loaded side arms, and a motor, crank or tape-pull operator.

Portable, pop-up canopies

A portable pop-up canopy or tent provides a cost effective temporary solution to people who want to enjoy shade. The portable designs offer versatility to take the unit to social events. The frame usually incorporates an accordion style truss which folds up compactly.

olar Shade Screens

Shade screens utilize acrylic canvas or a mesh fabric, which allows some view-thru while blocking the sun's rays. The roller at the top may be hand-cranked or motorised. The fabric is gravity-fed, with a weighted bottom rail pulling the fabric down between guide rails or guy wires. Exterior shades are much more effective at blocking heat than interior shades, since they block the heat before it enters the glass. This style of framed screens is typically done by professional installers, because of the specialized frames and tools required. A recent advancement is frame-less shade screens, which allows a "DIY-er" to install their own exterior shades.

Trade organizations

Industrial Fabrics Association International ( [http://www.ifai.com/ IFAI] ) is a trade organization which includes the awning trade, with a division called the Professional Awning Manufacturers Association ( [http://www.awninginfo.com/ PAMA] ).

Classification numbers

Construction Specifications Institute (CSI) Division 10 MasterFormat 2004 Edition:

* 107313 - Awnings
* 107316 - Canopies
* 107113.43 - Fixed Sun Screen
* 107300 - Protective Covers (Generic)

CSI MasterFormat 1995 Edition:

* 10530 - Protective Covers, Awnings & Canopies

References

ee also

* Brise soleil
* Tent
* Umbrella