Roofing Tips & Maintenance

Why Roof Ice Forms in Ithaca, NY and Why Fixing the Root Cause Matters

JD Ferro

January 12, 2026

If you own a home in Ithaca, NY, chances are you’ve dealt with roof ice buildup or ice dams during the winter. With our lake-effect snow, frequent freeze-thaw cycles, and long winters, roof ice is more than just an inconvenience — it’s a warning sign that something deeper is going on in your home.

Understanding why roof ice occurs and why it’s critical to address the underlying causes can save you thousands of dollars in roof repairs, interior damage, and energy loss.

What Causes Roof Ice and Ice Dams?

Roof ice — most commonly in the form of ice dams — happens when heat escapes from your home and melts snow on your roof. That melted snow flows down to colder roof edges and refreezes, creating a dam of ice.

Over time, this ice buildup prevents proper drainage, forcing water back up under shingles, where it can leak into your home.

Common Causes of Roof Ice in Ithaca Homes

1. Poor Attic Insulation

Many older homes in Ithaca and the surrounding Finger Lakes region were built with insufficient attic insulation. Warm air rises, and without proper insulation, heat escapes through the roof, melting snow unevenly.

2. Inadequate Attic Ventilation

A properly ventilated attic stays close to outdoor temperatures. Poor ventilation traps warm air, accelerating snowmelt and ice formation along the eaves.

3. Air Leaks From the Living Space

Gaps around light fixtures, bathroom fans, chimneys, and attic hatches allow warm air to leak directly into the attic — a very common issue in older Ithaca homes.

4. Complex Roof Designs

Dormers, valleys, and multiple rooflines — common in historic Ithaca neighborhoods — create cold spots where ice forms more easily.

Why Ice Dams Are a Serious Problem

Ignoring roof ice can lead to:

Roof leaks and interior water damage
Mold growth inside walls and ceilings
Rotting roof decking and fascia boards
Premature shingle failure
Damaged gutters and downspouts

Many homeowners remove ice year after year without fixing the cause — which is why the problem keeps returning.

Why Removing Ice Alone Isn’t Enough

Roof raking and ice removal only provide temporary relief. The real issue isn’t the ice — it’s heat loss and poor airflow.

If your roof forms ice every winter, your home is telling you something is wrong with the attic system.

How to Permanently Fix Roof Ice Problems

Improve Attic Insulation

Keeps warm air inside your home instead of escaping through the roof.

Seal Air Leaks

Air sealing around attic penetrations dramatically reduces heat loss and is one of the most cost-effective upgrades available.

Upgrade Attic Ventilation

Balanced intake and exhaust ventilation keeps the attic cold and dry — essential in Ithaca’s winter climate.

Install Ice & Water Shield

When replacing a roof, ice and water shield along eaves and valleys adds critical protection against ice dam-related leaks.

Why This Matters in Ithaca, NY

Ithaca’s heavy snowfall, temperature swings, and proximity to Cayuga Lake make ice dams more common here than in many other regions.

Work With a Local Ithaca Roofing Expert

Roof ice is a building science issue, not just a roofing problem. A local contractor who understands Ithaca’s climate and housing styles can identify the root cause and recommend long-term solutions.

If you’re seeing roof ice, icicles, or winter leaks, schedule a professional inspection before the damage starts.

Roof ice is a symptom — fixing the cause is the solution.

Contact us today or call (607) 753-9949 to get started today.

Roofing Tips & Maintenance