Roof-coating technology has grown leaps and bounds in the past decade, making restorative roof-coating systems a true alternative to re-roofing low-slope roofs. Not only is the cost of most systems 25 to 30 percent the cost of a total tear-off and replacement, but manufacturers are now also offering warranties lasting anywhere from 5 to 12 years. Another benefit to restorative roof coatings is the limited disruption to your facility's everyday operations. And, finally, restorative coating systems just might pay you back by adding an ENERGY STAR®-rated reflective surface, reducing your cooling utility costs, and possibly meeting requirements for tax deductions or rebates from local utility companies.
Good Candidates
Age of roof. When your current roof system is between 10 and 15 years old, usually right before its existing warranty expires, it makes sense to have your roof inspected and assessed to see if it is a good candidate for a roof restoration. By restoring the roof, you are not only extending its life, but you're also adding warranty protection for up to another 12 years.
Positive drainage and limited ponding. A roof that has positive drainage or does not pond or hold standing water longer than 48 hours following precipitation is usually an excellent candidate for restorative coatings. This doesn't mean that a roof which ponds in limited areas won't be a candidate. Adding a drain, tapered insulation, etc. can eliminate the ponding area, making the roof a candidate for coating.
Minor leak history. Leaks usually mean wet insulation. If your roof has more than 15- to 25-percent wet insulation, it should be replaced - the cost benefits of restoration are not viable at this point.
Regularly maintained. It's been well documented that regularly maintained roofs provide a longer service life. So, if your roof systems are maintained and leaks are fixed immediately, it will most likely be a candidate for restoration.
Two roofs. According to most local building codes, buildings can only be overlaid with a second roof system, not a third, limiting your options. Restorative coating systems are not considered a third roof and, in fact, can be used again and again as long as the roof remains a good candidate.
Steep-slope or other odd-angled roofs. Since coatings today are designed to adhere with little or no sag, depending on the product, steep-slope or odd-angled roofs are excellent choices for restoration.
Poor Candidates
Extensive leak history or ponding. If your roof has an extensive leak history, you probably have significant wet insulation. To determine just how much, core samples or an infrared moisture scan can assess the percentage of wet insulation.
Roof contaminants. Grease, chemical contaminants, or other like substances tend to make poor restoration candidates because of possible adhesion problems.
Restorative coating systems are truly an option for most roof systems. With the inherent cost savings in these types of systems, it's worth the investigation to see if your roofs are viable candidates.
Penny Gift is technical product manager for Republic Powdered Metals (www.rpmrepublic.com), a Medina, OH-based restorative coating and single-ply manufacturer.
