Many homes and buildings throughout the United States and the world have flat or low-sloped roofing systems. From time to time these flat roof systems may require a maintenance roof coating in order to extend the life of these systems. Coating applications, also known as roof sealant, are relatively simple projects and can be completed by most homeowners and building owners.
Can my roof be coated?
The first question that you must ask before you can coat your roof system is “Can my roof system be coated?” In order to determine if your roof system can be coated you must first determine what type of roof system you have. There are many types of flat roof membranes available on the market and installed on homes and buildings.
Some membrane types do not require coatings in order to be maintained. Some membrane types do require a coating in order to maintain the roof system in good working order. And still others can be coated for reflectivity and energy savings, but do not require a maintenance coating. It is important to understand what type of roof you have to avoid applying the wrong coating to the roof system which can cause damages to the roof membrane that can only be repaired through a complete roof replacement.
In order to determine if your roof system can be coated, it is best to determine the roof system type and the manufacturer of the product. Once you have determined the type of roof membrane and manufacturer, it is recommended that you contact the manufacturer and request information on the types of coatings that can be applied. If the incorrect coating is applied to your roof system it may void the manufacturer’s warranty.
A Word of Caution
Asphalt based coatings (e.g. aluminum roof coatings, etc.) should only be applied to asphalt based roof systems. Asphalt coatings will do damage to most single ply roof systems including EPDM (rubber), TPO and PVC roof membranes. If these coatings are applied to these types of membranes the only repair your roof will be to remove the contaminated membrane in entirety and replace with new membrane.
When should I coat my roof?
There are two factors that you want to consider when determining when you should apply a coating to your roof system. The first of these factors are the weather conditions that are available for completing the installation. It is recommended that you check with the coating manufacturer to determine the weather conditions that are required to complete the installation of the coating without compromising the quality of the installation. In general, it is recommended that the coating process be installed when the weather is moderate in temperature and no precipitation is predicted.
The second factor to consider is the age of your current roof system. If your roof system is newer in age, the coating application can be negatively affected by the oils that are present on your roof membrane. This can be particularly true when dealing with asphalt based roof assemblies such as BUR (built-up roof membrane) and MOD BIT (modified bitumen). These products are manufactured using petroleum and as a result the surface of the products can have oil residue on them. This oil residue can negatively impact the adhesion of the coating that you are applying. It is best to allow the roof system to weather after installation for several weeks or months prior to the application of a roof coating.
To Coat or Not to Coat?
Roof coatings are a proactive step in preventative maintenance. They will assist you in maintaining your roof assembly and maximizing the service life of your roof. However, coatings are only as good as the roof surface that they are being applied to. Many people believe the false assumption that you can seal a leak. If your roof system is severely aged or is leaking, it may be best to consider replacing the roof instead of coating it.