Last updated: August 2026
Independent ASTM lab testing by PRI Construction Materials Technologies measured how bio-based rejuvenation affects aging asphalt shingles. It found the treatment restored shingle flexibility and reduced granule loss by about 46% on 17-year-old shingles. That's strong evidence the treatment does something real — but it's laboratory testing, not a decades-long field study, which is exactly why our added-life claims stay conservative.
Who is PRI, and what does "ASTM testing" mean?
PRI Construction Materials Technologies is an independent testing laboratory — a third party, not the product manufacturer and not us. That independence matters: it means the results weren't produced in-house by whoever is selling the treatment.
ASTM refers to the standardized test methods published by ASTM International, an organization that writes the technical procedures used across the building-materials industry. When a lab runs an "ASTM test," it's following a published, repeatable procedure rather than making up its own. So "independent ASTM testing by PRI" is shorthand for: a neutral lab measured the product using recognized industry methods.
What did the lab actually measure?
The testing looked at properties that matter for how long a shingle lasts, not vague impressions of "looking better." Two results stand out:
- Restored flexibility. Aged shingles get stiff and brittle as their oils cook out. The testing found that treated shingles regained flexibility — the ability to bend rather than crack, which is what lets a shingle survive freeze-thaw cycles.
- About 46% less granule loss on 17-year-old shingles. Granules are the protective layer on top of a shingle. In testing on 17-year-old shingles, treated samples shed roughly 46% fewer granules than untreated ones — meaning the treatment helped the granules hold on.
Both of those tie directly to the mechanism we describe elsewhere: the treatment penetrates the shingle rather than coating it, restoring the oils that keep asphalt flexible and help granules stay put.
What does the testing prove — and what doesn't it prove?
This is where we want to be careful and honest, because it's easy to oversell lab numbers.
What it does support: that a bio-based rejuvenant measurably changes an aged shingle's physical properties in the right direction — more flexibility, less granule loss. That's meaningful. It's the difference between "we think this works" and "an independent lab measured it working."
What it does not prove: a lab test is a controlled snapshot, not a decades-long study of real roofs weathering real Pennsylvania winters. It doesn't, by itself, prove a specific number of added years on your particular roof. Restoring flexibility and slowing granule loss are strong indicators a treated shingle should last longer — but "should last longer in testing" and "guaranteed to add X years on your house" are not the same claim, and we won't pretend they are.
Why does our warranty use a concrete number instead of a big promise?
Because we'd rather stand behind something we can actually back. Each treatment restores flexibility that we warranty for a concrete 5 years, with a transferable 5-year warranty; with periodic re-treatment, many asphalt roofs gain 10–15 years of added service life. We use those specific, modest figures precisely because the evidence is lab testing plus real-world experience — not a promise pulled from thin air. A concrete warranty term is our way of turning "the lab shows it works" into something you can hold us to.
So how should a homeowner weigh this?
Treat the lab testing as what it is: credible, independent evidence that the treatment does something real to an aging shingle, from a neutral lab using standard methods. Then weigh it against the honest limits — it's testing, not a field study — and against a concrete warranty you can actually rely on. If you want to see how we present all the evidence together, our does it work? page lays it out.
Have questions about the testing or whether your roof is a good candidate? Book a free inspection and we'll walk you through it in plain terms.