Fall and winter tend to be the hardest on roofs. That’s when leaves fall, the rain starts, and there is snow and hail that can slam into your roof and cause all sorts of damage.
But there’s no season that is truly safe for any roof. In summer, for example, our weather patterns here can produce many situations that accelerate wear on the roof in ways that even winter and fall do not. It’s also a time when vulnerabilities in existing roofs get exposed, causing potential short and long term issues that become even more important to get repaired by fall.
Heat and UV Damage
Asphalt shingles absorb heat. On a July afternoon in New York City, a dark-colored roof surface can reach temperatures well above 150°F — far hotter than the air around it. That level of heat, repeated day after day across a full summer, degrades shingle material faster than almost any other single factor.
UV radiation compounds the problem. The same sunlight heating the roof is also breaking down the asphalt binders that hold shingles together. Granule loss accelerates in summer for exactly this reason — the coating that protects the underlying material from UV exposure wears away faster when that exposure is at its most intense. By the end of a New York summer, a roof that was borderline in spring has often crossed into genuinely compromised territory.
Thermal expansion and contraction also affects the roofing materials in the long term. During hot days, the shingles heat up, and when it cools at night they contract. This happens repeatedly over the course of the season. That cycling stresses the material and the fasteners holding it in place, contributing to lifting, curling, and seam separation over time.
Moisture, Humidity, and Mold
New York City summers are humid, and roofs absorb and retain that humidity in ways that create problems beyond the visible surface. Attic spaces that lack adequate ventilation trap heat and moisture, which accelerates deterioration of the roof deck from underneath. A roof can be failing from below while looking unremarkable from the street.
Moss and algae thrive in summer humidity, particularly on north-facing roof sections and areas shaded by trees. Neither is cosmetic — moss holds moisture against shingle surfaces and speeds up the breakdown of the material underneath it. Algae produces dark streaking that many homeowners mistake for dirt, but it indicates biological growth that warrants treatment before it spreads further across the surface.
Flat roofs common on Staten Island and Brooklyn properties face their own moisture challenges in summer. Standing water — from rain that didn’t fully drain — sits on the membrane and creates conditions for blistering, seam separation, and eventual penetration. Heat accelerates all of those processes.
Summer Storms and Wind Damage
New York summers bring thunderstorms, and sometimes severe ones. High winds lift shingles that were already marginally secured, separate flashing that was beginning to fail, and deposit debris — branches, leaves, and other material — that can puncture or abrade roof surfaces.
The damage from a summer storm often isn’t dramatic. It may cause a few lifted shingles or a section of flashing to shift. They’re not particularly problematic at the time, so few people inspect their roof – not unless storm rain starts to come through the ceiling. But left unaddressed, each of those things creates a pathway for moisture that progresses through the fall and winter.
Pest Problems
Pests are dormant in winter but highly active in summer. Wildlife are the biggest concern. Animals like squirrels running across a roof can begin to damage already deteriorating shingles, and rats that have access to the roof can begin to chew on the asphalt or leave droppings in ways that cause significant damage.
But other pests can be a problem as well. If there is any minor damage, pests may use those entrance points to their advantage and begin entering, causing further damage to the roof as they move in and out or feed on the surrounding wood.
What Summer Damage Looks Like From the Ground
Most of the damage summer produces isn’t visible from inside the house — it shows up on the roof surface and in the attic before it ever produces an interior symptom. Some of the signs visible from the ground include:
- Dark Streaking or Staining — Algae growth producing dark lines or patches across the shingle surface, most common on shaded sections of the roof.
- Visible Granule Loss — Bare or thin patches on shingles where the protective coating has worn away, often visible on lower roof sections near the eaves.
- Lifted or Curling Shingles — Shingle edges lifting away from the roof surface, particularly on ridges and at roof edges, where thermal movement is most pronounced.
- Sagging Gutters — Gutters pulling away from the fascia or visibly sagging, indicating debris buildup or damage from storm activity.
- Missing Shingles — Gaps in the shingle surface, most commonly caused by wind during summer storms.
Any of these warrant a closer look before they progress further into the roofing system.
The Case for a Late-Summer Inspection
The strongest argument for a roof inspection in late summer is timing. A problem identified in August or September can be addressed before the freeze-thaw cycles of winter — which are what turn minor roofing issues into significant structural ones. Water that gets beneath a compromised shingle in October, freezes, expands, and thaws repeatedly through the winter produces damage far more extensive than the original entry point.
Christian Construction provides roof inspections and roofing services throughout Staten Island, Brooklyn, and parts of New Jersey. To schedule an inspection or get an estimate for any summer roofing damage, call 718-447-6475 or reach out through the contact form on the website.
