Metal has been a common roofing material of commercial buildings in the US for quite some time. In the recent past, as other options have been developed and become available, metal roof usage has decreased. Metal roofs can still be seen on many roofs, both because they were previously installed and have a long lifespan, and because they continue to be installed today. They are decreasing in popularity, but they are still a viable flat roof option.

Advantages of Metal Roofs

Rusted metal roof needs replacement 

Metal roofs are favored by many facility managers because they are durable, non-combustible, and can reflect some heat off of your roof. The surface can become extremely hot when the sun beats down on it, but a lot of that heat is prevented from entering the building which saves you on energy costs. There are some estimates that say you can save up to 30% on heating and cooling costs compared to other roofing materials. For repairs of metal roofs, you cannot solder as you could in the past with terne or copper roofs. Instead, you’ll need to use aluminized caulk or fiberglass for larger patches.

Another advantage many people find with metal roofs is that they can be custom formed around flashings, protrusions and other irregular roof features. While they are typically manufactured in large standardized sheets, there are some customization options available to roofing contractors as they prepare to install.

Disadvantages of Metal Roofs

The substrate can be described as “clunky”, as it is very heavy and often difficult to work with. It is also one of the more permanent roofing options, meaning replacement is significantly more difficult than most other substrates, unless a spray-applied coating is elected.

The fact that they require complete tear out in almost every replacement instance a huge downside of this substrate. Rather than being able to install a new roof layer over top of the metal roof, in most cases you will need to tear the metal roof completely off. They are also at a great risk of rusting, which greatly compromises the strength and ability to protect the building from water as holes can develop.


Metal roofs are a durable, long-lasting flat roofing option, but they are not without their downfalls. Be careful to always consult a professional and consider more factors than only cost if you are looking to replace your roof. If you have questions, you can give us a call and we’d be glad to give you any more information you may need. If you don’t think the metal roof as a flat roof replacement is right for you, we’ve got posts on other flat roof replacement options available