Urethane Roof Coatings
At American WeatherStar, we offer a variety of different fluid-applied roof coating systems to protect and restore both flat and metal roof surfaces. Once applied, these systems not only stop and prevent roof leaks, they reduce HVAC system workloads, improve the look of your building, and most importantly, save you money!
Urethane roof coatings are just one of the many chemistry types that we incorporate into our fluid-applied roofing systems. With that in mind, let’s examine the benefits and limitations of urethane roof coatings and what factors you should consider before installing a urethane roof coating system on your building.
What Are the Benefits of Urethane Roof Coatings?
Urethane roof coatings are most commonly used for sprayed-in-place polyurethane foam insulation and almost every other commercial roofing substrate. Without a doubt, urethanes are one of the strongest, most durable roof coatings on the market today. That being said, what benefits do urethane roof coatings offer, and what does that mean to building owners and managers?
Aliphatic vs. Aromatic
There are two main types of urethane coatings: aliphatic and aromatic. Aliphatic urethane coatings are UV stable, hold color longer, resist dirt pick-up, and are typically used as a top coat. Aromatic urethane coatings are not quite as UV stable, less expensive, and typically used as a base coat.
Extreme Durability & Flexibility
Urethane roof coatings form a highly durable, flexible, and seamless membrane layer that can withstand the daily expansion and contraction of the roof structure, and resist ponding water. Urethane coatings are more impact resistant than any other coatings, making it ideal for use in high-traffic areas.
Urethane roof coatings adhere very well to most traditional commercial roofing substrates including: metal, modified bitumen, smooth BUR, spray polyurethane foam, EPDM, TPO, and other single-ply membranes.
Excellent UV Protection
Urethane roof coatings are highly reflective and UV stable, meaning building owners and facility managers can save money by reducing cooling costs during the hot summer months. Minimizing the sun’s impact on the roofing surface not only helps to sustain lower energy costs as the system ages, it reduces internal building temperatures, and helps extend roof life.
What Are the Limitations of Urethane Roof Coatings?
There are a number of factors to consider when choosing a fluid-applied roofing system for your building. While urethane roof coatings do offer many important benefits, it’s just as imperative to acknowledge the limitations of the product.
Produces a Strong Odor
Urethane roof coatings do emit a strong, xylene-based odor. For buildings that have a fresh air intake HVAC unit, we highly recommended that it be set to recirculate air from within the building, or turned off completely during the installation process.
Can Be Challenging to Spray
As with any solvent-based coating, urethane roof coatings can be difficult on hydraulic spray equipment and challenging to spray. Issues during the installation process are less likely to occur if the spray equipment is properly cleaned and maintained.
Shorter Shelf Life
Single-component urethane coatings, unlike plural-component urethane coatings which will not cure until mixed, are constantly curing—even in the pail.