I’m in the process of getting solar installed and was looking for something to make my asphalt roof last at least as long as the panels (since it costs more to get them removed and reinstalled than it does to get them installed), and I wanted something that would make my roof white since up to 40% of summer cooling costs can be saved by having a white vs black roof (and yes even coloured asphalt shingles are mostly black, they just look coloured from a distance). I looked at a number of different sealers and liquid rubber coatings and while this one was a bit more expensive than others in terms of per 5-gallon pail, the math of coverage and number of coats required (500 sqft/pail and only 2 coats) it was FAR more cost effective than the others. Unlike other options, it is also specifically made for shingles (rather than general roofs or general waterproofing applications), and comes with a 10 year warranty (versus 5 year for most others). After talking with a rep, they suggested actual life expectancy should be closer to 20 years and should be looked at as an extension on the lifespan of the shingle it is on (ie. a 25 year shingle becomes a 35 to 45 year shingle).
It also came in clear as well as multiple other opaque colours, one of which was white.
The most interesting concept for me though was their suggestion that reapplying one additional coat every ten years would extend the life of the roof indefinitely.
Granted with solar panels in place that would require removing them every 10 years to do a complete roof re-coat, but in my mind, since the panels protect the roofing below to a large extent, as long as I re-coat around the panels (and perhaps as far under as I can get) the result should be the same.
So I went ahead and ordered up six 5 gallon pails, (just shy of what the coverage suggested I needed for a 1600 sqft roof) and they arrived about 4 days later.
What comes is a pail of yellowish white liquid, which I assume is the “clear” version once it dries, because it also comes with a bag of coloured powder that you have to mix in (which takes about 10 minutes to mix in thoroughly with a drill-type mixer).
I couldn’t find a roofer in my area who wanted to paint, or a painter who wanted to go on a roof, so I ended up doing it myself.
Don’t bother using a tray, just use a big mug, pour out a line and then spread it out with a 19mm roller on a pole. Roll it perpendicular to the lines of shingles, and make sure to stop at the edge of a line and you will avoid lap-lines, and also paint the front edge of the shingles (which doesn’t happen if you go parallel to the shingle lines).
The first coat used up 4 of the 6 gallons so I thought I might need more but the last two did the second coat no problem since it didn’t get sucked in so much. I also did the first coat on two very hot, sunny days and the sealer dried very quickly on the hot roof (around 5-10 minutes), which probably also negatively affected coverage, whereas the second coat i did on overcast days and it stayed wet for a good 20-30 minutes at least.
In terms of heat gain, at the beginning of the second day when the sun was barely up, the un-treated roof was already on the verge of too hot to touch whereas the treated roof was cold, like a stone countertop, and it was still only half-way to white since it was only the first coat.
Now that it’s done, the second floor of the house is much more livable on hot, sunny days (no noticeable difference to cool overcast days), and the roof itself has a hard plastic feel to it that feels WAY more durable than typical shingles.
The solar panels haven’t been installed yet but I have no doubt the roof will last as long as they will if not longer just off this initial application, but I will probably still re-coat exposed areas ever 10 years just to be safe