Grease, oil, and fingerprints can be removed by using low-alkali washing agents; even acetone can be used. This should be done as soon as possible after the surfaces get dirty. Abrasive washing agents such as ammonia or chlorides should not be used.
Various metal polishes can be used to clean slightly oxidized surfaces. For example, a 5% citric acid liquid is an environmentally and user-friendly option.
Nordic Copper facades should only be cleaned with cold water, without further additives. Windowsills can be cleaned with a damp cloth regularly (approximately every 4 weeks) in order to remove bird droppings or other deposits. Facade elements can be freed of dust and leaf debris with a water hose or pressure washer (at low pressure) approximately every 12 months. It is not advisable to use chemical cleaning agents because these are very damaging to the copper surface and can harm the desired weathering effect (discoloration, oscillation, darkening). When cleaning windows, care should be taken that no chemical agents come in contact with the reveals, windowsills, and lintels, and the areas should be wiped off with a cloth afterwards. Leaving handprints on copper window frames, reveals, and windowsills while cleaning them can also lead to significant changes in the weathering effect, which cannot be completely removed.
Clear coats help preserve the natural finish. A clear coat may be as simple as a coat of wax or as advanced as a hi-tech acrylic lacquer. The choice depends on the situation.
Special coatings: Available as matte and glossy with anti-fingerprint protection and graffiti protection. Coatings provide permanent surface protection against further weathering of the copper/copper alloy. A coated copper surface can be cleaned with mild cleaning agents and water.
The coatings are mainly used indoors.
Special wax is a natural, temporary surface protection. Wax is not permanent and doesn’t just prevent fingerprints. Wax slows down the oxidative reaction of the surface and, like the waxing of natural wood floors, can be renewed regularly.
Wax can be used indoors and outdoors. It does not stop the general, natural development of the living copper surfaces like a varnish, but simply slows down this process. Waxing copper surfaces is a tried and true remedy.
Care should be taken when using copper above or close to mortar, cement, marble, stone, and other porous materials. Water runoff from copper surfaces may cause bluish stains on these materials. Construction measures are recommended to prevent such stains: using longer overhangs, directing flowing water away from other materials with slants and gutters, and installing drip edges.
On the construction site, no milling and cutting work should be carried out on alkaline materials (granite, concrete, stone, etc.) in the immediate vicinity of the Nordic Copper facade.
The resulting dust can settle on the copper surfaces and lead to strong oxidative traces.
All Nordic Copper materials are weldable and solderable.
Of course, the mechanical strength must match the respective application and be checked. The correct welding technology must also be used (TIG and MIG and WIG).
When using special film (laser protection film) to further process Nordic Copper products, special care must be taken to ensure that the film does not remain on the surfaces for longer than 14 days.
Adhesive residue and oxidative staining on the surface may be an issue if these instructions aren’t followed.
After completion of a facade, the protective film should be promptly removed from the copper elements if possible.
Keeping film on the facade in strong sunshine, rain, and cold weather leads to oxidative changes in the Nordic Copper products, which usually can’t be undone without impairing their appearance.
Copper also turns green today, but it takes significantly longer than 50 years ago. This is due to the cleaner air and less intense environmental influences. A copper roof in Central Europe is only really green after at least 75-90 years. A facade needs even more time – it can be over 100 years, depending on the intensity of the weather.
Yes, copper is 100% recyclable over and over again, without any loss of quality.
Yes, in general all Nordic Copper products can be processed in these ways.
Lasering is only possible to a limited extent on patinated surfaces such as Nordic Green and Nordic Blue. Oxidized surfaces such as Nordic Brown, Nordic Brown Light, and Nordic Brass Weathered can be lasered easily.
All Nordic Copper products can be edged, cut, punched, and embossed.
Metals are rated according to how noble they are. When dissimilar metals are in contact with each other in the presence of oxygen and moisture, the more noble metal will corrode the less noble metal. Copper is one of the most noble metals and must be separated from other, less noble metals. Painting, bonding, or sealing with non-absorptive materials provides effective protection from galvanic corrosion.
According to recent investigations, copper-containing water slightly corrodes anodized pure aluminum (oxide layer thickness 20 μm) but only impacts its decorative appearance and not its function. Direct contact between these two materials without the described surface coating should still be avoided.
Today, aluminum components are usually provided with colored coatings (coil coatings, powder coatings, anodized coatings, etc.). These components can of course be combined with those made of copper without any problems. Slight corrosion can then only occur on the unprotected cut edges of the aluminum parts under unfavorable conditions. With regard to many copper facade projects carried out worldwide, we recommend that aluminum parts in direct contact with copper be powder-coated.
Graffiti protection is a sensitive topic, especially when it comes to buildings in public spaces. Generally speaking, it’s possible to seal copper surfaces with an anti-graffiti coating. However, this causes the copper to lose its natural surface and thus some of its benefits and its character, as the coating prevents the ongoing natural development of the surface. As an alternative to traditional anti-graffiti coatings, there are other cleaning options in the meantime (e.g., dry ice blasting) and innovative cleaning products that help remove graffiti gently without the prior application of a coating. For copper, there is also the option of cleaning the surface abrasively and then allowing it to naturally oxidize afterward so that the natural surface appears again over time.
Copper strip, sheet, and profiles must be stored indoors in dry conditions and at a constant temperature with low humidity. The surfaces must be protected from scratches resulting from dust, sand, etc. Direct contact with alkaline dust should be avoided, e.g., from screed, concrete, concrete saws, plaster, etc. because oxidation changes can occur. Material with a film should also be protected from direct sunlight because heat and UV radiation can age the protective film faster and cause an unwanted adhesive quality on the material surface.
The protective film should be removed from the material as fast as possible during installation. Cotton gloves have to be worn in order to avoid handprints, sweat, and other impurities on the copper surface. Before using rubber gloves, they should be checked on a sample piece for wear and tear and to determine if traces of material are left on the copper surface. During installation, hands must be kept oil-free.
Mixing metals creates new materials with new properties; these materials are called alloys. Copper can be alloyed with many metals.
The most important alloy families and their main components are as follows:
- Copper-zinc: brass
- Copper-tin: tin bronze
- Max. 5% copper with other elements: low-alloyed copper materials
- Copper-nickel-zinc: nickel silver
- Copper-tin-zinc: gunmetal
When working on copper, the same metalworking tools that are used in plumbing and sheet metal technology can be used as for aluminum and zinc. For patinated surfaces, the tool should be taped before use in order to avoid spalling and scratches. Patinated surfaces are very sensitive and should be handled with the utmost care. Slight spalling of the pre-patination may occur in folded areas. However, this does not represent a defect or functional deficit.
The weathering of all Nordic Copper products is completely project-dependent.
Depending on the external environmental influences (air pollution, humidity, heat, UV radiation, surrounding production facilities, surrounding construction sites, proximity to the sea and lakes), the Nordic Copper products can change faster and more intensely.
With Nordic Copper products, tendencies in natural weathering can be shown based on older original samples. However, these do not represent a guarantee that this development will take place in all projects.
Even an aluminum bronze alloy (Nordic Royal) can be dark and uneven as it develops due to the environmental influences described.
Each facade side will experience a different weathering intensity due to its direction, resulting in different oxidative color ranges.
Surface grindings like those of the Nordic Décor products generally lead to faster oxidative darkening and, depending on the grinding pattern (regular or directional), to uneven, changing oxidative surface appearances.
The term “architectural bronze” is a non-technical name that is still used for the material CuZn40Mn2Fe1. This is a special brass, i.e., a copper-zinc alloy with additional alloying elements. Bronze is the technical term for copper-tin alloys.
That is why the name “architectural bronze” for a brass material is very unfortunate and causes more confusion than clarity.
In the Nordic Copper family, architectural bronze can be visually compared with our burnished brass alloy CuZn15 Nordic Brass Weathered.
WHAT ARE THE DIFFERENCES BETWEEN FACTORY-BURNISHED NORDIC BRASS WEATHERED AND HAND-BURNISHED NORDIC BRASS?
Nordic Brass Weathered – factory-burnished
- Is foiled.
- Can be fully folded with foil.
- Can be delivered as a sheet or coil.
- Sheets up to 6 m long and 1 m wide are possible.
- Lower prices.
- Material is manufactured in its entirety, does not have to be individually worked and burnished by the sheet.
- If required – stock material available in Germany for very quick access within 24 hours.
- Nordic Décor grindings can be individually determined and applied after burnishing.
- Nordic Décor can be adjusted in the mill just-in-time during the meeting with the architects.
Nordic Brass – hand-burnished
- Not foiled.
- Very expensive, long production time.
- More transports, individual production.
- No stock material, has to be manufactured individually.
- Sheet lengths generally limited to 3.2 m.
- Not manufactured in one production process but in individual sheets. Therefore, different charges possible in the burnishing.
In our experience, the effort to burnish and install an individual piece of brass is significantly higher and bears no relation to the use of the factory-burnished brass. In addition, the surface development in both options goes in the same direction, namely that the surface continues to darken.
In this case, you can save yourself the costly additional effort and longer delivery and production times of individually burnished brass. Our suggestion is to choose a brass that has been pre-weathered at the factory with a Nordic Décor finish (e.g., peg cut 990). This can be determined directly at a meeting in the mill.
The material is delivered foiled. It is already cut into sheets if desired. At the same time, stock material is in storage so that the material can be accessed as quickly as possible during the construction process. This gives you a clear, regulated flow of production and delivery for the installation and a cost-optimized, individualized solution.
Solid copper is in fire protection class A1 – non-combustible. It can therefore be installed in all conceivable applications and also in high-rise construction without restrictions.
The term verdigris is unfortunately often used in an incorrect context. Verdigris is a water-soluble salt of acetic acid in connection with copper and it is often confused with patina due to its color. However, verdigris can never assume the protective function of patina due to its water solubility and does not occur in construction due to the lack of acetetic acid.
The well-known green color of copper components in roofs and walls is solely due to oxidation products (non-water-soluble Cu(I) oxide) of copper and must not be confused with verdigris.