Lifespan by roof type
These are the ranges Long Island roofers publish. Where they disagree, both ends are shown.
| Roof | Typical life on Long Island | Where the number comes from |
|---|---|---|
| 3-tab asphalt shingles | 12 to 25 years | MK Best, Jannace, Expressway |
| Architectural shingles | 20 to 35 years | North Shore, Jannace, Expressway |
| Flat roof membranes (EPDM, TPO) | 15 to 30 years | North Shore, County Roofing |
| Cedar shake | 25 to 35 years, less facing the ocean | Rapid Roofing |
| Synthetic slate | 30 to 50 years | Rapid Roofing, MK Best |
| Metal | 40 to 70 years | North Shore, Expressway |
| Natural slate | 60 to 100+ years | Rapid Roofing, LI Roofing Co. |
Jannace’s rule of thumb is worth keeping in mind for any of these: most roofs get about 80 to 85% of the life on the warranty.
What wears roofs out faster here
Wind. North Shore Roofing says nor’easter gusts on Long Island can easily pass 80 mph. Every big storm loosens a few more shingles and breaks a few more seals.
Salt air. Within about two miles of the water, North Shore says corrosion of nails, flashing and valleys speeds up. Home Team Construction adds that it accelerates granule loss on asphalt.
Freeze and thaw. North Shore counts 60 to 80 freeze-thaw cycles a year. Water that gets into a crack freezes, expands and makes the crack bigger.
Ice dams. Meltwater backing up under the shingles at the eaves rots the deck from below.
A hot attic. Jannace says poor ventilation “cooks” shingles from underneath, and Home Team notes dark asphalt can hit 150°F or more in summer sun.
Algae. The black streaks on so many Long Island roofs are algae. MK Best says it eats the limestone filler in shingles.
A bad install. Jannace lists poor flashing, underlayment and nailing as reasons roofs fail early, whatever the shingle.
Signs it is near the end
- granules collecting in the gutters, or bare patches on the shingles
- shingles curling, cracking or turning brittle
- a sagging roofline
- daylight through the roof boards when you are in the attic
- damp insulation or mold around vents and chimneys
- ice dams every winter
- more than one leak at a time
One leak around a chimney is usually a repair. Several leaks on an old roof usually is not.
Getting more years out of it
Jannace, citing InterNACHI, says maintenance can add five to ten years. On Long Island that mostly means keeping gutters clear before winter, making sure the attic is vented, and fixing a small leak before it becomes rotted decking.
