Can a coating really add 10 years to an aging asphalt shingle roof?

On the Fine Homebuilding Podcast's episode 761, released Oct. 30, senior editor Patrick McCombe took the question to Ian Schwandt and Randy Williams. He said the magazine first heard about these products through an Instagram question about a reader's mother's small house in Florida, and that he was skeptical from the start. McCombe likened the coatings to the ones used on RVs and the sales pitch to the aluminum siding craze of the 1950s and 1960s, then asked whether elastomeric coatings have any real place on houses.

The Asphalt Roofing Manufacturers Association, the shingle makers' trade group, has a clear answer. Its technical bulletin, posted July 24, 2026, covers both coatings and so-called rejuvenators and says ARMA strongly advises against applying either in the field over installed asphalt shingles. Many manufacturers specifically recommend against such treatments on their products, the bulletin says, and state or local codes may forbid them because a treatment can change the fire classification, algae resistance or impact resistance of the roof assembly.

ARMA lists problems reported on treated roofs: coatings that shrink and curl or cup the shingles, granules that come loose, and nonpermeable films that seal the gaps around shingles and can hold moisture in the roof. The group says there is little documentation that the products deliver what sellers claim, such as a longer roof life, lower energy bills or sealed small leaks. Many also need repeat applications to keep a uniform look.

Before anyone sprays a roof, ARMA says to get the shingle manufacturer's position on that specific product and to check with the local building department and any homeowners association.