The Roofing Resource Blog

Understanding the Difference Between Metal Roof Coatings

Thu, Dec 11, 2014 @ 10:47 AM | Exterior Pro Roofing

Metal roofing is a strong and durable roofing material that many people prefer over other materials. However, in order to keep your metal roof in the best shape possible, it may require coating. Understanding the different types of coating available will help you make an informed decision concerning which type of coating is best for you. Currently there are over one thousand products on the market specifically for metal roof coating. This can be an overwhelming amount of options.

Some of these substrate types are generally used in commercial roofing, which may simplify the decision making process. You can make a cost effecting choice by educating yourself on these types of coatings to find out which is appropriate for your situation.

Before making a choice, however, you will need to check local, state and federal building codes to make sure you are in compliance with their regulations concerning roof coating. It is also important to check out the requirements for your particular roofing system if there is any.


Urethane coatings are a two part system that works well on metal roofs. This type of coating provides excellent elongation and high tensile strength. The tensile strength you will see with this coating is about 1,500 pounds per square inch. This is a great improvement to the usual 200-400 psi provided by other coatings.

metal roof coating


Polyurea helps create a much harder surface than that which you will find with other types of coatings. In fact this type of coating is typically 100 percent solids. This means that they offer the same advantages as a water based coating would offer as far as volatile organic compound regulations or fire risk. However, this type of coating does have some limitations related to cure rate.



Silicone is another type of metal roof coating that many people find appropriate. Silicone works great over SPF roofing systems which require a coating. SPF roofing systems require several steps in order to install properly, so making sure that you have chosen the best coating is an important decision.

If you are going to be recoating a roof that already has an existing coating, you will need to make sure you are choosing a coating that will adhere well to the existing coating. Not all materials will recoat one another.Check manufacture’s details to find out if you are choosing the best coating for a recoat.

Many consumers are confused over the fact that coating a roof may be necessary, because most roofing systems come with a factory applied coating to begin with. The problem is that weather and harsh conditions can erode this coating over time, making it necessary to recoat after a while. This is why after market metal roof coatings are now in demand.

In most cases workers should apply a primer before applying the surface coating on a metal roof system. It does not matter the roof’s age. This step should be done carefully as primer and coating combinations are very specific. Contact the coating manufacturer to get specific guidance on how to best prepare your metal roof system for surface coating.