In 2011, a roofing company in Florida was criticized by the National Roofing Contractors Association (NRCA) for making use of field-applied coating for asphalt tiles. Although the coating was designed to beat the Florida heat as a reflective layer, reports about roof degradation surfaced right after installment. The "green" effort was commendable, but safety was a different issue.
In response, the Florida Building Commission thought about modifying a couple of code provisions to deal with using cool roof coatings on asphalt roof shingles. For the record, this kind of roofing in Wilmington is not made to accept any kind of coating. The NRCA and the Asphalt Roofing Manufacturers Association (ARMA) share similar thoughts on this matter. In a few months, roofs around the country will be subjected to summer heat; the advisory can not be timelier.
The ARMA isn't searching for a total ban on field-applied coatings, but a thorough examination of the coatings used. The coating may consist of chemicals, particularly solvents, which may utterly destroy the asphalt material on the shingle. The more asphalt a shingle loses, the less effective it is at minimizing overflow; thus, the roof will be more susceptible to leakages.
Most coatings on asphalt shingles, if any, are often factory-applied; most roofers do not see the need for a second coating. It's quite similar to carrying more cargo than what the vehicle allows. A tile that's very heavy will put unneeded stress on the entire roofing system.
As a final note, the ARMA recommends asking the manufacturer and referring to local building codes regarding coating shingles. So far, there have been no irrefutable findings about how useful field-coated shingles are as cool roofing systems. Bear in mind that asphalt shingles need no coating or paint and roofers in Winston Salem will most likely install them as is. Should you decide to have the tiles coated on the spot, be ready for any issues that may surface.
Roofing materials work better when you use them as instructed by the manufacturer. To know more about this story, check out the articles at DurabilityAndDesign.com. Ask your roofing contractor about coating asphalt shingles to be informed.
Asphalt Roofing in Wilmington: What Re-coating It Does