Zinc installation is different than the installation procedure for other metals. For that reason, Umicore requires the attendance in one of its VMZ Pro-zinc® training courses. For more information on the VMZ Pro-zinc® training courses please view the Contractor Services on this website.
These training courses provided by Umicore Building Products help installers to understand the basic properties of zinc. Installers also learn zinc's limitations. Attendance is unconditional, but Umicore will not provide its standard product warranty unless at least one person in the installation crew has attended and received a certificate for the VMZ Pro-zinc® class.
Even though zinc will form a natural protective barrier, precautions should be taken during installation to ensure that no damage, deformities, or color variations occur. Zinc installers should always wear gloves and long-sleeved shirts when handling the zinc. The acidic nature of perspiration will leave marks on the zinc surface that will heal over time but will remain visible for a while and could have an adverse effect on the appearance of the zinc immediately after installation.
The protective film should be removed from zinc panels upon completion of an elevation, all at the same time. The protective film should remain on the zinc no longer than 60 days after the completion of installation. Make sure that other trades will not contaminate zinc panels after the film is removed.
A minimum slope of 1:12 must be used on all surfaces, including parapets, copings, and flashings to ensure that standing water doesn’t occur. The minimum slope for the roof system may be greater for the roof to be water resistant. See the appropriate installation manual for more information on minimum roof slopes.
Cold Weather Installation
During installation in a cold atmosphere, zinc may become brittle. Zinc should not be colder than 45ºF or 7ºC or it may crack. Zinc that is going to be installed in weather colder than 45ºF or 7ºC should be heated prior to working with it. Typical tricks of the trade are to use heated seamers or to keep the zinc under a heated blanket.
Some zinc panel systems can be installed in cold weather provided that the installation does not require altering the panels (bending, crimping, drilling holes, etc.).
Before installion, the surface below zinc roofing panels and flashing must be protected to prevent water penetration. VMZ compatible weather barrier should be used as a slip-sheet to allow the zinc roofing panels to expand and contract freely. If a high temperature membrane is needed, then the membrane should be able to withstand temperatures of greater than 250ºF (120ºC). Unprotected bituminous membrane should not be used.
Soldering Recommendations and Techniques:
Use 50/50 Lead/Tin Solder. The soldering iron should be an adjustable temperature soldering iron.
1) Preparing Zones for Soldering
In preparation for soldering, the zinc must be stripped of any factory-induced patina to the natural (shiny) finish. Umicore recommends using Stay Clean flux for stripping the zinc prior to soldering. These stripped zones should only be as large as necessary to accommodate the soldering needed. For any zinc with a coating, such as PIGMENTO, a mechanical grinder should be used for stripping.
2) Soldering Prepared Areas
Place the two pieces to be soldered together and the solder with the aid of a bar of tin-lead solder (50/50) in the following steps: 1) spot soldering, 2) smooth soldering, 3) reinforced barred soldering.
Umicore recommends attending its VMZ Pro-zinc training course to learn the proper techniques of soldering zinc.
Caulks and Sealants
Polyurethane caulks and sealants are compatible with zinc. Caulks or sealants with an acidic cure must be avoided, as they will corrode the zinc. The caulk or sealant must be able to sustain high temperatures for extended periods of time. The maximum temperature for QUARTZ-ZINC is 176°F (80°C) and the maximum temperature for ANTHRA-ZINC is 194°F (90°C).
|Recommended Caulks and Sealants|
|Dow 795||metal to metal, metal to glass|
|SikaFlex 1a||metal to metal, metal to masonry|
|SikaFlex 2c||metal to metal, metal to masonry|
|SikaFlex201||metal to metal, metal to masonry|
Do not cover the zinc with a tarp as it will cause condensation build-up and will eventually lead to white rust formation. Use plywood board if the zinc needs to be protected. Make sure that the plywood board is kept away from the zinc surface to allow water to drain and air to flow over the zinc surface, and prevent any run-off from the board onto the zinc.
Due to human chemical makeup, fingerprints are visible on zinc. Installers should be advised (in the specification) to wear gloves and long-sleeved shirts to minimize prints. Apply Umicore mineral oil (Strub oil) to make the fingerprints less visible. The mineral oil also enhances the patina formation. It must be used on the entire elevation to avoid color differences.
Construction dirt and dust on unprotected zinc can be gently removed with a clean cotton cloth and warm tap water.
For graffiti removal, use "Max Swipes" by Graffiti Solutions, Inc. and/or "Goof Off" from W.M. Barr & Company. Follow their instructions for proper use. See the manufacturer website for more details. Applying any chemical on the zinc may alter the finish. Use cleaning agents with caution.
If a scratch appears, the zinc will heal itself overtime. If the scratch is extremely deep, consider replacing that particular panel.