When installing a metal roof, it is important to realize that a system of individual components is being installed that are related to each other, and that depend on the proper installation of each part in order for the system to perform correctly. Understanding this “family of products” and how they are related will make any installation job easier, safer, and less confusing.
Metal roofing has always been considered a premium roofing material. A brief look at how metal roofing developed over the centuries will help the installer understand why and how various roof styles, types of panels, materials, and seam methods were developed. Each was developed to solve a roofing problem. Some were developed to meet unique roofing situations.
“Metal Roofing: A Family of Products”
A typical metal roof system is composed of five primary components an installer needs to consider in any application. They are:
Roof panels & trim
Common roof accessories
The substructure is the foundation, or base, to which the top roof panel is attached. Think of it as the first thing that is found when the roof’s top layer is pulled back. The two main types of substrates are called solid deck and open framing (Figure 2-1). Decking material may be either wood or metal, and some substrates may have rigid insulation.
Roof panels and trim make up the top layer of the roof and are directly exposed to the weather and the environment. These products can be made from:
- Natural metals
Metallic coated materials
They may be in the form of sheets, panels, or smaller individual pieces, much like traditional asphalt shingles, wood, slate, or tile facsimiles. The sizes and shapes of metal panels and trim pieces may vary widely, but are light in weight, and usually easy to install. (Figure 2-2) Most panel styles and varieties are available painted or unpainted