Pallets of moisture-cure roof coatings

While there are many benefits to moisture-cure roof coatings, it is critical to have a basic understanding of best practices for storing and working with these chemicals. Some of the characteristics that make these materials so effective can also cause them to ruin if not properly managed.

Moisture-Cure Coatings: 5 Best Practices

  1. Always keep materials covered on the job site out of the rain and direct sunlight. A tarp tied down will do the job.  Make sure no moisture cannot get into the lids. Rain is the obvious concern but morning due can also be a potential problem. The coatings actually begin to cure in the pail when moisture is present resulting in clumping material. This problem is also a manufacturing and transporting issue. All parties involved should be cognizant.
  2. When working with moisture-cured urethane and silicone, plan to use materials on the day they are opened whenever possible. Humidity enters the drum or pail as soon as the lid is removed. Stirring the material is essential before applying; just remember that stirring also helps the material begin to cure by adding moisture and heat.
  3. It is acceptable to add small levels (5-10%) of pure mineral spirits to silicone or xylene to urethane. The keyword here is pure! All too often contractors purchase recycled solvents unknowingly from a paint store. Recycled mineral spirits have small amounts of water causing the coating to “kick-off” the curing process. Check out this short video on cleaning solvents.
  4. Never apply a coating to a wet or damp surface. The moisture-cured urethane is especially sensitive to coming in contact with a damp area. The material will cure but will lose the physical characteristics it needs to perform on the roof.
  5. Work quickly once the material is open. A fast-setting material is just that. It begins to set as soon as you open the lid and start working with it. If you are in a hot and humid area of the country, it is important that you keep a quick pace.


Our Ure-A-Sil, Envir-O-Sil, and Met-A-Sil Systems are all comprised of moisture-cure coatings. This type of coating has proven itself in the industry for over 30 years. For best results, make sure you and your team follow these important best practices on how to store and install moisture-cure coatings.