In traditional Georgian and Roman architecture, before the advent of modern housing support infrastructures, the corners of buildings often needed extra support in order to sustain the weight of multiple stories and stone roofs. This was particularly true of castles and major Medieval and Victorian estates and cathedrals. Architects charged with constructing such buildings frequently achieved corner support with the use of a quoin. A quoin is a block, usually of stone or brick, that is placed on the corner junction between load-bearing walls. Quoins typically jut out from the corner but can also be inlaid, and in any event give a variegated, almost striped appearance to a building’s corner.
Quoins had a very important role to play in traditional architecture. They diverted and distributed weight, relieving pressure on the stone walls they sat between. Without them, the walls would have been unlikely to have been structurally sound, and many would have collapsed before construction was even complete.
The result was also aesthetically pleasing, as they created a unique visual diversion and a sense of depth and interest. The use of quoin rock and quoin stones quickly became synonymous with the nobility and wealth. Most of the homes occupied by peasants and commoners were too small to require quoin support, and architectural services were never cheap.
Modern architecture in the West continues to embrace the aesthetic elements of the quoin, although quoin use is very rarely functional anymore. Modern architectural techniques allow for walls and buildings to be supported internally without extra corner supports. Also, houses and buildings in the 21st century are rarely, if ever, made exclusively of stone.
Although countries like the United States, Australia, and Canada have never known truly ancient buildings or resident nobility, the architectural preferences of these bygone beings continues to captivate homeowners and business developers in these markets. Decorative quoins can be seen on houses and office buildings around the world. They are generally believed to lend class and an old-world feel to buildings, particularly those of stone or brick.
Decorative quoins must nonetheless be planned by architects with a bit of foresight. With few exceptions, quoins cannot be added to a building after construction. A decorative brick quoin or limestone quoin is inlaid into the original structure or façade a it would be as a structural support, but usually not to the depth or extent of a functional quoin.
Oftentimes quoins are highlighted by the use of bricks or stones in a color that contrasts with the rest of the wall. Even uniformly-colored quoins impart a unique and noticeable look, however. Stucco quoins are an example of quoins that are almost always the same color as the rest of the structure. Stucco quoins are usually affixed to the exterior of an already-finished corner, but are typically anticipated by prepared grooves and inlets introduced during construction. Stucco quoins can sometimes be added to buildings that were not designed with quoins in mind, but this is not usually recommended.