History
Copper has played a role in architecture for thousands of years. For example, in ancient Egypt, massive doors to the temple ofBenefits
Corrosion resistance
As an architectural metal, copper provides excellentDurability/long-life
Copper roofs are extremely durable in most environments. They have performed well for over 700 years, primarily because of the protective patina that forms on copper surfaces. Tests conducted on 18th Century copper roofs in Europe showed that, in theory, they could last for one thousand years.Low thermal movement
Properly designed copper roofs minimize movements due to thermal changes. Copper's lowLow maintenance
Copper does not require cleaning or maintenance. It is particularly suited for areas that are difficult or dangerous to access after installation.Lightweight
When used as a fully supported roof covering, copper is half the weight (including substrate) of lead and only a quarter of tiled roofs. This generally provides savings in supporting structure and materials costs. Copper cladding offers additional opportunities to reduce the weight of copper structures ''(For more details, see:Ventilation
Copper does not require complexRadio frequency shielding
Sensitive electronic equipment are vulnerable to interference and unauthorized surveillance. These products also require protection fromLightning protection
Wide range of finishes
It is sometimes desirable to chemically alter the surface of copper or copper alloys to create a different color. The most common colors produced are brown or statuary finishes forDesign continuity
Architects often look to architectural copper for continuity in design elements. For example, a copper roofing system may be designed with copper flashings, weatherings, vents, gutters, and downpipes. Cover details may include cornices, moldings, finials andAntimicrobial
Extensive worldwide tests have proved that uncoated copper and copper alloys (e.g., brass, bronze, copper nickel, copper-nickel-zinc) have strong intrinsic antimicrobial properties with efficacies against a wide range of disease-resistantSustainability
While a universally accepted definition of sustainability remains elusive, theRecyclability
Recyclability is a key factor of a sustainable material. It reduces the need to mine newCost effectiveness
Performance, maintenance, service life, and recovery costs from recycling are factors that determine the cost effectiveness of building components. While copper's initial cost is higher than some other architectural metals, it usually does not need to be replaced during the life of a building. Due to its durability, low maintenance, and ultimatePure vs. alloyed copper
Pure copper. Unlike other metals, copper is frequently used in its pure (99.9% Cu) unalloyed form for sheet and strip applications in roofing, exterior cladding, and flashing. Tempering is a heat treatment technique used to increase the toughness of metals. Tempers determine theSelection criteria
The criteria by which copper and copper alloys are selected for architectural projects include color, strength, hardness, resistance to fatigue and corrosion, electrical and thermal conductivity, and ease of fabrication. Appropriate thicknesses and tempers for specific applications are essential; substitutions can lead to inadequate performance. Architectural copper is generally used in sheet and strip. Strip is or less in width, while sheet is over in width, up to in width by in length, plus in coil form.Structural considerations
Structural considerations play an important role in the proper design of copper applications. The primary concern is about thermal effects: movement and stresses related to temperature variations. Thermal effects can be accommodated by preventing movement and resisting cumulative stresses or by allowing movement at predetermined locations, thereby relieving anticipated thermal stresses.Joining
Copper and its alloys are readily joined by mechanical techniques, such as crimping, staking, riveting, and bolting; or by bonding techniques, such asSealants
Sealants are an alternative to solder where additional strength is not required. In most cases, sealants should not be necessary with a properly designed copper installation. They are at best a relatively short-term solution requiring frequent maintenance. Regardless, sealant-filled joints have been used successfully as a secondary waterproofing measure for standing seam and batten seam roofing applications where low-sloped roofs are less than . Sealants can also be used in joints that are primarily designed to accommodate thermal movement of the copper. The sealants used should be tested by the manufacturer and designated as compatible for use with copper. In general,Galvanic corrosion
Galvanic corrosion is anNatural patinas
Copper goes through a naturalFinishes
Copper and its alloys can be 'finished' to embark a particular look, feel, and/or color. Finishes include mechanical surface treatments, chemical coloring, and coatings. These are described here. Mechanical surface treatments. Several types of mechanical surface treatments exist. Mill finishes are derived by normal production processes, such as rolling, extrusion, or casting. "Buffeted" finishes impart bright mirror-like appearances after grinding, polishing, and buffing. "Directional textured" finishes provide a smooth, velvety satin sheen in a continuous pattern of fine nearly parallel scratches. "Non-directional textured matte" finishes achieve a rough texture, primarily on castings, as spray sand or metal shot are applied under high pressure. And "patterned" finishes, made by pressing a copper alloy sheet between two rolls, produce a textured and embossed look. Chemically induced patina. Architects sometimes request a particular patina color at installation. Factory-applied chemically induced pre-patination systems can produce a wide range of colored finishes similar to natural patination. Pre-patinated copper is particularly useful in repairs when there is need to provide close color matches to old copper roofs. Pre-patination is also considered in some modern building materials, such as vertical cladding, soffits, and gutters where patination is desired but would not ordinarily occur. Chemical coloring of metals is an art involving craftsmanship and experience. Coloring techniques depend upon time, temperature, surface preparation, humidity and other variables. Pre-patinated copper sheets are produced by fabricators under controlled environments using patented chemical processes. Green patina finishes are primarily developed using acid chloride or acid sulfate. Treatments with ammonium chloride (Applications
Craftsmen and designers utilize copper's inherent benefits to build aesthetically pleasing and long-lasting building systems. FromRoofing
Copper offers a unique character and durability as a roofing material. Its appearance can complement any style of building, from traditional to modern. Its warmth and beauty make it a desirable material for many architects. Copper also satisfies demands of architects and building owners regarding lifetime cost, ease of fabrication, low maintenance, and environmental friendliness. The installation of copper roofing is a craft requiring experienced installers. ItsFlashing
While most modern construction materials are fairly resistant to moisture penetration, many joints between masonry units, panels, and architectural features are not. The effects of natural movement due to settlement, expansion, and contraction may eventually lead to leaks. Copper is an excellent material for flashing because of its malleability, strength, solderability, workability, high resistance to the caustic effects of mortars and hostile environments, and long service life. This enables a roof to be built without weak points. Since flashing is expensive to replace if it fails, copper's long life is a major cost advantage. Cold rolled hard temper copper is recommended for most flashing applications. This material offers more resistance than soft copper to the stresses of expansion and contraction. Soft copper can be specified where extreme forming is required, such as in complicated roof shapes. Thermal movement in flashings is prevented or is permitted only at predetermined locations. Flashing installed incorrectly can promote line corrosion and shorten the life of valley flashing, especially in acidic environments. The risk is most prevalent at the leading edge of shingles where the shingle edges rest on the copper flashing. Through-wall flashing diverts moisture that has entered the wall before it can cause damage. Counterflashing diverts water to the base flashing, which, in turn, diverts it to other materials. Various types of copper flashings and copings exist. Diagramatic explanations are available.Gutters and downspouts
Leaking gutters andDomes, spires and vaults
There are many types of copper domes,Wall cladding
Copper cladding has become popular in modern architecture. The technology enables architects to incorporate visually desirable features into their designs, such as embossed or shaped-metal cladding. Cladding enables structures to be made with much less weight than solid copper. composites weigh , only 35% as much as solid copper of the same thickness. Copper cladding is used in building exteriors and indoor environments. On building exteriors, copper cladding sheets, shingles, and pre-fabricated panels shield buildings from the elements, acting as first line of defenses against wind, dust, and water. The cladding is lightweight, durable, and corrosion resistant, which is particularly important for large buildings. Common interior applications includeBuilding expansion joints
Designing for the movement of building components due to temperature, loads, and settlement is an important part of architectural detailing. Building expansion joints provide barriers to the exterior and cover spaces between components. Copper is an excellent material for expansion joints because it is easy to form and lasts a long time. Details regarding roof conditions, roof edges, floors, are available.Indoor design
Copper aesthetically enhances interior wall systems, ceilings, fixtures, furniture, and hardware by evoking an atmosphere of warmth, tranquility, and calm. Regarding performance advantages, it is lightweight, fire resistant, durable, workable, and non-organic (it does not off-gas). Typical copper-based interiors include panels, shingles, screens,Green buildings
Sustainable materials are key elements ofAwards
Award programs highlight copper architecture installations in Canada and the U.S. and in Europe. An International Copper and the Home Competition also exists.International Copper and the Home CompetitionSee also
*References
{{Reflist, 30em Copper Architectural design Architectural elements Sustainable architecture Corrosion Roofing materials