Monday, November 20, 2017

YOU CAN'T BEAT COPPER

Replica of the copper axe carried by Otzi the Iceman, who
lived between 3400 and 3100 BCE.  He was discovered
in the Otztal Alps on the border of Austria and Italy in
1991. 
Only a handful of building materials can claim to have been in use for thousands of years:  wood, stone, brick.  And perhaps most remarkable of all, copper.

Copper was one of the first metals known to man, and was in use as early as the fifth century BCE.  Most ancient copper was mined on the island of Cyprus—hence its name.  Alloyed with tin, copper formed the prize metal of the Bronze Age, and thereby played a crucial role in the ascent of man.

As a building material, copper’s durability is legendary as well. The most important monuments of Baroque architecture were fitted with copper roofs and gutters, many of which are still in service after centuries. One reason for copper’s longevity is that, over years of exposure, it forms a protective oxide “skin” that protects the metal below and produces the familiar blue-green patina known as verdigris.
Copper-roofed spire of the Baroque
Church of St. Nicholas, Prague,
begun in 1703.

This brings up copper’s other great strength: its timeless beauty. Unlike chromium and other perishable metals, whose appeal is based on their initial luster, copper grows more attractive the more weathered it becomes. In fact, mellow, aged copper is actually more prized than the spanking-new variety—so much so that impatient folks are even willing to pay a “patinator” to artificially hurry up the process.

Nowadays, copper’s high first cost, as well as its unstable market price, makes many people reluctant to use it in their projects. But first cost isn’t the only consideration when specifying materials, or we’d all have plastic gutters and tarpaper roofs. Durability and appearance both need to be factored into material choices. And if long life and beauty are your main concern, copper is just plain unbeatable. Here are a few places to consider using it:   
Copper pipe—a familiar, reliable,
and affordable building material.

•  Supply and waste piping is probably the most familiar use of copper in construction, and remains unchallenged for durability. Moreover, copper piping is affordable to all but the very tightest budgets.  

•  Copper gutters (starting at around $25 per lineal foot installed) are far more durable than galvanized sheet metal, and require no painting—they’re simply allowed to weather to a handsome patina. As with all uses of copper in construction, only compatible fasteners can be used to attach copper gutters, since fasteners of dissimilar metals can create electrolysis problems that’ll lead to corrosion. This will lead to failure of the fastener, not the copper.
Detail of copper roof eave/gutter,
Frank Lloyd Wright's Robie House
in Oak Park, Illinois (1909).

•  Copper roofing (around $15 per square foot) is generally considered the premium choice for durability and appearance.  The parallel ribs or “standing seams” used to join the individual sheets of copper give this roof its characteristic appearance, as well as providing the ultimate in watertightness.  

•  Copper lighting fixtures achieve a beautiful patina just about the time most plated fixtures start getting pitted and ugly. If you can’t find a fixture that suits you, however, consider having one custom-fabricated. Practically any design that can be formed from galvanized sheet metal can also be fabricated in copper, and the price is often competitive with store-bought fixtures.

•  Lastly, a bit of philosophical advice:  The building materials industry is rife with wannabe materials and unproven claims of durability. When it comes right down to it, though, the only rock-solid evidence of worth is how a material performs over time.  Say, oh, about two thousand years? 

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