We started a full shingle roof replacement on a two-story home in Fontana on October 6. Here is why this roof was a replacement and not a repair, what was under the old shingles, and what is going back on. I'll add the finished roof when it's done.
Two reasons, and either one would have started the conversation. The roof was leaking, and the shingles were at the end of their life. When both are true, a patch only buys time until the next rain finds the next weak spot. I wrote about how I make that call in Repair or Replace?.
So this one is a full tear-off. Every shingle comes off, down to the wood, and nothing new goes on until we've seen what's under there.
Day two in Fontana. New shingles on the lower roof, the second story down to the wood.
This house has a board deck: rows of solid wood boards under the roof instead of plywood sheets. Tear-off day is the only day anybody gets to see every one of them, so that's the day to deal with them.
We kept the boards that were sound and replaced the bad ones. No reason to throw out good wood, and no reason to cover bad wood with a new roof.
The second story down to the board deck, with the Duration COOL bundles staged up top.
ProArmor synthetic underlayment goes over the whole deck first. That's the layer that keeps the water out if anything ever gets past a shingle. Then Owens Corning Duration COOL shingles, on the whole house. How we install Duration, layer by layer, is on our Owens Corning Duration page.
New Duration COOL over ProArmor on one side, the old deck waiting on the other.
Fontana is in California's Climate Zone 10, going by the state's ZIP code lookup. In that zone, when you replace more than half of a house's roof, the state energy code calls for a cool roof on a sloped roof like this one: a minimum aged solar reflectance of 0.20 and thermal emittance of 0.75, or a Solar Reflectance Index of 16. The code allows a few other paths too, like enough attic insulation, and it has some exceptions, so check the rule for your address.
Duration COOL is the version of Duration with reflective granules, and it's what we use to meet that requirement.
As I write this, the lower roofs have their new shingles and the second story is on its way. I'll add the finished roof here when it's done.
Tear-off day is the only day you see every board. That's the day to fix them.
Sources: California Energy Commission, 2025 Energy Code, section 150.2(b)1I; California Energy Commission, building climate zones by ZIP code.
Free in-home estimate, in writing. We'll tell you straight whether it's a repair or a replacement. We do asphalt shingle roofs, tile replacement with new tile, tile lift and relay, and flat roofs across the Inland Empire.
(909) 819-8394