Three-tab was standard through this era and rated around twenty years. Curling and cupping means the mat has lost its oils and the shingle no longer seals. Once curling is general rather than local, patching is spending money on a roof that is finished.

This is most common in homes built roughly 1940 to 1980. Post-war and mid-century — copper supply, aging cast iron stacks, 60 to 100 amp panels, first-generation central air.

Related

• Two or three layers of shingle already on the roof
• Plank decking with gaps between the boards
• Rust streaks below the chimney flashing
• Wood shingle under the asphalt
• No ridge vent and no soffit intake
• Valley metal rusted or missing
• Masonry chimney needs work
• Sagging visible along the ridge line

Back to Roofing.

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Written by Jaylan Jones. I Like To Exterior Services earns a referral fee when a call connects to a contractor. See our business-model disclosure.