The stunning copper roofing turret featured in today's architectural blog article is fashioned from custom diamond shaped copper roof tiles and is topped with a spear shaped copper finial turret roof cap. This lovely turret copper roofing graces and enhances this beautiful new home undergoing final stages of construction. Additional custom copper work includes copper flashing, half round copper gutters, round copper downspouts and copper leader heads adorned with copper lion head castings. Radius round copper gutter encircling the base of the copper turret roof is planned.

Buildings, including residential, commercial, public, and industrial consume about one third of all energy use and about two thirds of all the electricity generated. Demand for electricity in the U.S. is increasing three times faster than new power plants and lines are being built to accommodate this rapidly increasing demand. Heating and cooling costs dominate most building's energy usage. A building's roof can have the greatest impact on the energy consumption by a building so any technological advances and improvements in roofing energy efficiency and performance will greatly affect both energy usage and consequent cost savings. Energy efficiency, durability, performance, sustainability, recyclability and life cycle costs are the focus of green building. Architects, builders and consumers have been changing the way they select building materials and designing buildings. They are increasingly shifting their focus to green building materials and energy performance with so called cool roofs becoming a key focus. Cooling costs significantly affect a building's energy consumption in most parts of the country and cooling is the predominant cost in the southern states. Cool roofs can save up to 40% in cooling energy as reported by several studies including Lawrence Berkeley Laboratory Heat Island Group. Cool roofs essentially are roofs which reflect much of the sun's radiation away from a building, employ above sheathing ventilation (ASV) cooling under the roof, readily emit any heat which they do absorb back away from the building and cool quickly at night. The less solar radiation and heat entering a building's interior space through the building's roof, the lower the building's cooling costs and energy use will be.

Today we share a few pictures of some wonderful seamless gutter system installation, copper roofing and other types of copper work in the South West Florida coastal area including Naples and Ft Myers. The corrosive salt air environment being right on the Gulf of Mexico makes copper gutter systems and other architectural copper work the longest lasting and best solution due to copper's excellent corrosion resistance, durability and weatherability. Copper is also a very green building material and all the copper can be recycled 100% at the end of it's up to 90 plus year lifespan.

Roof domes are one of the most visually striking and appealing architectural structures around. Domes have been around for thousands of years. Ancient cultures constructed mostly corbel or arched dome dwellings using locally available materials such as mud, clay or adobe. The earliest discovered domed structures may date from around 15,000 to 20,000 years ago in the Ukraine, constructed from mammoth bones and tusks. In ancient times people lived in such domed structures and in more modern times Native Americans constructed wigwams from curved branches and hides and much farther north, igloos from compressed blocks of snow. Pygmies in Africa used mango leaves to cover their similar dome shaped structures. Ancient domes discovered in the Middle East were used for modest structures, such as tombs. The early Romans while constructing smaller domed structures for villas, palaces, baths and tombs also constructed very large, advanced true domes over large interior spaces such as temples and public buildings. True domes are traditionally considered to be a self-supporting hemi-spherical shape structure or roof. Half a hemispherical dome is called a semi-dome and other variations of that are generally called false domes. All of the different types of domes essentially still have a curving or rounded top. Over hundreds of centuries domes have been constructed from a large variety of building materials including mud, clay, stone, brick, wood, concrete, metal, glass and in recent times even plastic. Next we look at some early, historic or notable domed buildings and feature especially those with copper roof domes.

The European Copper in Architecture Awards are biennial awards which recognize excellence in design for European architectural projects incorporating copper roofing, copper wall cladding and other copper architectural design elements. The 15th iteration of the awards will officially be launched in September 2010 for architectural projects completed between April 2009 and May 2011 with the judging and presentation of awards occurring in 2011. The previously concluded 14th European Copper in Architecture Award competition celebrated the use of copper in architecture in all of it's forms and selected the best in contemporary copper architecture from across Europe. Some of the European Copper In Architecture award winners are described and shown below.

Each year the North American Copper in Architecture Awards acknowledges and spotlights selected North American building projects for innovative and exceptional use of architectural copper. The architectural copper awards program highlights a wide scope of projects which highlight craftsmanship, attention to detail, and architectural vision. Copper has historically long been used for its great natural beauty and finish, it's durability and performance, copper's long service life and recyclability. Copper is still today a superior building material and also one of most eco-friendly and green building materials, which is being utilized and adapted for an ever wider variety of contemporary and cutting edge building and architectural applications. Three of the twelve copper in architecture award winners are described and shown below.

Waipolu Gallery and Studio, Oahu, Hawaii
(photo credits Nic Lehoux, Vancouver, BC - Courtesy Copper.org)

The Waipolu Gallery above uses copper wall cladding and copper roofing which were chosen for this project as copper will perform well over a very long time and with very little maintenance in a very corrosive ocean side location. Copper's beauty and fluidity compliment the modern art contained within the structure. The copper provides a softer contrast to the other more linear materials used. Excellent workability or malleability of copper was advantageous allowing easy re-working or shaping on site. The building architects also like there will be changes in copper's patina or color over time, producing an ever evolving work of art. The studio with it's stainless steel, glass and concrete linear space is joined by a floating glass bridge to the copper clad gallery. The glass bridge rises above a limestone staircase which connects the building's three levels.

The Mark Olsen Project exhibits excellent old world craftsmanship, with a copper roof and other architectural copper features such as copper finials, copper gutters and ornamental downspouts with copper conductor heads, copper crown molding, fascia and soffit, copper chimney top shroud and extended copper window box. This stately home has exquisite detailing and exudes quiet elegance from it's naturally weathered copper features. 16,000 pounds worth of hand crafted architectural copper work are used for this home's architecture. The copper roof is comprised of diamond shaped interlocking copper shingles, copper ridge vents and flashing. Of note, no sealants were used, only traditional craftsmanship and installation techniques were employed along with some soldering work on the copper gutters providing very long term durability with little to no maintenance required.

One hundred fifty years in the making, the Cathedral of St. John the Baptist in Charleston, South Carolina has at long last been restored after being completely destroyed by fire in 1861. A soaring neo-gothic style copper spire, which had long been planned, was finally realized this past spring. The stunning beauty of the copper spire with it's gold leaf finished copper cross can be seen across the Charleston skyline and out to Sullivan Island. The cathedral's tower was finished with a stone veneer and at it's top there are four copper clad archways with copper torch finials. The copper spire with gold-leaf copper cross finial is perched on top at center of the copper arches. The 200 square feet of gold leaf which covers the cross will last at least 40 years without touch-up while the crowning copper art work comprised of arches, finials, spire and cross at the peak of the cathedral will last and stay beautiful for generations to come.

Gazebos are an outdoor pavilion or tent like structure which are usually round, square or octagonal in shape. A gazebo is a familiar sight, found just about anywhere, in parks, gardens, back yards, on a lake or seashore, outdoor restaurants, etc. Gazebos are usually roofed but open on the sides, sometimes with railings or balustrades and sometimes screened in. The gazebo floor might be grass, stone, concrete, brick or raised wood deck. The gazebo's base or deck and the optional railing usually follow along the bottom outline of the gazebo roof (round - square - octagonal - etc). A gazebo is oftentimes free standing in an open area or can be attached to another building or connected by decorative wall or path. Gazebos are popular spots, especially in warm weather, to rest, entertain, eat, relax and socialize. A gazebo provides shelter, shade and often seating and tables. Gazebos are unusually appealing structures and provide a most attractive and ornamental feature to a property's architecture and landscaping. The most common gazebo is built out of wood with ordinary roofing shingles used on the roof. A simple metal or copper roof cap with finial might be found on top. A gazebo upgrade might involve a small cupola perched on top of the gazebo roof, once again with a roof finial crowning the very top. The ultimate gazebo roof is a copper roof made from copper tile or copper panels. A copper gazebo roof may be conical in shape, bell shaped, octagonal, pentagonal, pyramidal, domed or any number of different shapes.
 

Galvanic Corrosion is an electrochemical process which occurs when dissimilar metals are in contact with each other in the presence of an electrolyte, most commonly being moisture and oxygen. For example rain water and salt water make especially good electrolytes. An electrolyte could be any non-metal matter that will conduct an electric current and are predominantly liquids or moisture. Every metal has been rated for nobility and then placed on galvanic scales according to nobility. Basically nobility is a measurement of the resistance to corrosion, especially of one metal contacting another metal. Metals that are the least noble means they are very anodic, electropositive or high potential and will corrode most easily. Whereas metals that are the most noble, means they are highly cathodic, electronegative or low potential and will be the most resistant to corrosion. The most corrosive effects will occur between metals from the opposite ends of the galvanic scale or ranking of nobility. This difference in electrical potential between two or more metals causes galvanic corrosion. Dissimilar metals in contact with each other in the presence of an electrolyte causes current to flow through their points of contact at the expense of the metal with the higher potential or less nobility. The much less noble metal is gradually consumed in the Electro-chemical reaction and will deteriorate or wear away as the metal ions migrate away from the very anodic metal to the more noble cathodic one. The more noble metal's corrosion resistance actually increases from this transfer of ions to it from the less noble metal, while the other metal is gradually getting consumed. Below is an abbreviated galvanic scale showing ranking of the most common construction metals from the least noble up to the most noble in a normal construction setting where both moisture and oxygen are present.

Galvanic Scale (Nobility of Common Metals)*
Least Noble
Aluminum
Zinc
Galvanized Steel
Iron
Stainless Steel – Active
Tin
Lead
Brass, Bronze
Copper
Stainless Steel – Passive
Titanium
Most Noble

Electropotential of Various Metals
High
Aluminum     +1.30
Zinc            +0.76
Chromium     +0.60
Iron            +0.44
Nickel          +0.22
Tin              +0.13
Lead            +0.12
Copper         -0.34
Silver           -0.80
Platinum       -0.86
Gold            -1.10
Low

Since dissimilar metals in contact with each other in the presence of oxygen and moisture will result in the less noble metal being corroded or eaten away the more noble one, contact between dissimilar metals should be avoided. For example, copper as one of the most noble of metals should be kept separated from less noble metal such as aluminum and galvanized steel. If contact between dissimilar metals cannot be avoided, their surfaces should be insulated as much as possible at the least with a non-metallic, non-conductive coating, such as bituminous or zinc chromate primers or paint. Separating the dissimilar metals with tape, gaskets, waterproof membrane, sealants or other non-conductive material that does not absorb and hold moisture can be used effectively. Care must also be taken to avoid the liquid wash run off or discharge from the drains from noble metals to less noble ones. For example rain water run off from a copper roof going into aluminum gutters and downspouts will result in traces of copper salts in the run off wash accelerating corrosion of the aluminum. Additionally, the use of galvanized nails, screws, flashing or drip edge on copper roofing or copper gutters should likewise be avoided as such less noble fasteners and metals will corrode rapidly. While rain water is a good electrolyte so too is high humidity or moisture laden air especially when it contains a high concentration of corrosive acids as is typically found in larger cities or near industry. In industrial or heavily populated areas, harmful electrolytes are formed by the absorption of gases by rain and fog to form acids and salts, while in coastal areas a saline electrolyte is formed by the combination of salt with the moisture laden air.
 
As copper has one of the highest galvanic numbers or nobility of construction metals, copper will not be harmed by contact with any of the common metals. However, copper will promote corrosion of other less noble metals if placed in direct contact with them. Copper can be used most appropriately with lead, tin, lead-tin solder or stainless steel under almost any circumstance. The primary metals of concern in terms of galvanic corrosion contact with copper are aluminum and zinc. Large differences in the thermal expansion rate between copper and these metals may cause additional problems. Also avoid using copper and some brass fasteners with aluminum, zinc and most ferrous metal. Paints or coatings that are used for isolation must be compatible with both of the dissimilar metals. The bituminous or zinc chromate primers and paints can be used between copper and aluminum surfaces. These same coatings or a red lead primer can also be effective in separating copper from iron and the other ferrous metals such as galvanized steel or mild steels.

Another type of corrosion called erosion corrosion is caused by the flow of acidic water concentrated into a very small area. While especially true for the least noble and most corrosive of metals, but capable of affecting all metals, acidic water allowed to concentrate on a small area, for example rain water from a large area like a roof diverted towards a flashing, valley or gutter can cause erosion corrosion. Also acidic water or liquids pooling on metal surfaces or trapped without air circulation between roofing or sheathing can quickly corrode the metal. Solution is to eliminate such pooling, maintain air circulation underneath metal roofs or between inert roofing material and drip edge, valleys and flashing. Another solution is to use replaceable reinforcing insulative strips between the inert materials and metal. Raw zinc and aluminum especially are susceptible to prolonged contact with acidic moisture, as for example the underside of a zinc roof. But care should be taken even with copper and stainless steel. Copper and zinc possess a superior property in that both will gradually develop a long term protective patina that helps guard against such corrosive effects for a very long period of time providing initial safeguards are exercised such as drying out provisions or temporary coatings.


*Note: Galvanic chart rankings involving sea water immersion and low oxygen conditions will vary somewhat - the more typical nobility given here is for land based construction.

For the framework we will be using aluminum tubing, plywood sheathing and waterproof membrane. We begin by precisely cutting square aluminum tubing to size and bending the tubes using a roll forming machine to form the base and the many vertical support cross members. A partially completed aluminum frame is shown below.


After all the plywood sheathing panels have been securely fastened in place with self-tapping screws, we then apply to the partially completed dome a self-sealing waterproof membrane, taking care to completely seal the dome. After the membrane is in place, we draw guidelines and begin carefully attaching the hand-cut copper tile to the dome and to each other. The copper tile have been designed to interlock securely with each other and we use copper ring shank nails to fasten them to the plywood.