Some architects or contractors are interested in commercial canopy designs that incorporate both aluminum and steel. These canopies are possible, and Mitchell Metals can provide them, but there are things we want you to know before you decide.
Advantages of Combining Steel and Aluminum
When you combine aluminum and steel in a canopy design, you are able to have longer spans between supports. This is a significant advantage in the metal canopy process because it will allow for a more unobstructed walkway as well as reduce the amount of canopy members needed, in turn lowering the cost.
In addition to the longer span length, a canopy made of aluminum and steel will have less framing support required in the structure.
Disadvantages of the Combo
There will, however, be issues when you set out to combine two dissimilar metals into one canopy design.
One of the disadvantages is that the design eliminates the ability to have internal drainage because downspouts will most likely be required, and you cannot drain water through steel which will rust. Also, clear spans become limited to the maximum length that decking can be ordered (which is 24′ -2”) when you combine the two metals.
Things to Be Aware Of
When designing a custom metal canopy that includes both aluminum and steel, you must be careful not to get too far away from the way an aluminum canopy system works. If you stray too far, it could compromise the integrity of the structure, or not drain properly. If you desire to combine the two metals, start with an aluminum canopy design, and see where steel could fit in.
During the installation process for a custom canopy like this one, bituminous coating is required to counteract a galvanic reaction between two dissimilar metals — to do this, you could use felt, acrylic, or paint coatings such as polyester or Kynar. Anodized materials must use felt or acrylic.
Another thing to be aware of is that mixing metals in a canopy design also requires the mixing of vendors. If a steel and aluminum canopy is what you desire, Mitchell Metals can provide the aluminum, but not the steel. We will work with one of our trusted steel providers to get you the exact design you are looking for. Contact us, or look at our specs to get more information.