Many homeowners believe that mold is a summer problem, fueled by warm temperatures and humidity. But that’s only half the story. In reality, mold can, and does, grow in cold weather, especially in areas like Central New York, where winter brings snow, ice, freezing temperatures, and moisture buildup in some of the most vulnerable parts of your home.

At Green Tree Environmental, we’ve seen firsthand how winter conditions create the perfect storm for hidden mold growth. Here we explain why mold doesn’t take the winter off, how to spot cold-weather mold, and what you can do to prevent it.

Mold Myth: Mold Can’t Grow in Cold Weather

Let’s start by clearing up a common myth: Mold doesn’t die in the winter—it goes dormant in freezing outdoor environments. But inside your home, where temperatures are regulated, and moisture is still present, mold can continue to grow all winter long.

Mold spores exist everywhere in the air. All they need to become a problem is:

1. A moisture source
2. A food source (wood, drywall, insulation, etc.)
3. Temperatures between 40°F and 100°F

In other words, your warm, insulated home is the perfect environment, even in the middle of a Central New York blizzard.

Winter-Specific Risks for Mold Growth in Central New York

In areas like Syracuse, Baldwinsville, Rome, Utica, and Cortland, winter brings unique mold risks that homeowners need to be aware of. Here are some of the most common culprits:

Ice Dams on the Roof

Ice dams form when warm air from your home melts snow on your roof. The melted snow refreezes at the edges, trapping water beneath the shingles. This water can seep into attics and walls, leading to mold growth in hidden areas.

Learn how to prevent ice dams and avoid mold growth.

Poor Ventilation

When homes are sealed tight against the cold, humidity and condensation can build up inside, especially in attics, crawl spaces, and around windows. Without proper airflow, mold has the moisture it needs to grow, even in cooler spaces.

Humid Indoor Activities

Winter means hot showers, cooking indoors, and using humidifiers, all of which release moisture into the air. If not controlled, this can contribute to condensation and surface mold on walls, ceilings, or around windows.

Heating Systems and Insulation Gaps

Heat loss through poorly insulated attics or basements can create cold spots where condensation forms. When warm, moist air hits a cold surface, it creates water, and that water feeds mold.

Where Mold Hides in the Winter

Mold can grow anywhere there’s moisture and organic material. In winter, we frequently find it in:

• Attics (due to ice dams and poor ventilation)
• Basements and crawl spaces (cold, damp, and poorly insulated)
• Window sills and frames (condensation buildup)
• Behind drywall or wallpaper
• Inside HVAC systems and ductwork
• Around humidifiers, vents, and radiators

Since many of these areas aren’t inspected regularly, mold can grow undetected for months, causing hidden damage and spreading spores throughout your home.

Health Risks of Winter Mold

The CDC warns that mold exposure can cause a range of health issues, especially for people with asthma, allergies, or weakened immune systems. These risks don’t go away in the winter. In fact, they may increase because:

• People spend more time indoors with closed windows, increasing exposure
• Central heating circulates airborne spores throughout the house
• Humidity levels may go unnoticed until visible mold appears

Symptoms of mold exposure in winter may include:

• Persistent cough or sneezing
• Skin or eye irritation
• Sinus congestion or headaches
• Asthma attacks

If these symptoms appear or worsen during winter, it could be due to hidden mold in your home. Learn how mold affects your health.

How to Prevent Mold Growth During Winter

Fortunately, winter mold problems are preventable with the proper steps. Here are some simple but effective strategies:

Control Humidity

Keep indoor humidity below 50%. Use exhaust fans in bathrooms and kitchens, and make sure your humidifier isn’t overdoing it.

Improve Ventilation

Install or unblock attic, crawl space, and soffit vents. In older homes, consider an air exchange system to balance humidity and airflow.

Monitor for Condensation

Check windows, walls, and cold corners of your home for moisture buildup. Dry condensation immediately and find the source.

Maintain Roofing and Insulation

Ensure your attic is adequately insulated and ventilated to prevent ice dams. Schedule regular roof inspections, especially after snowstorms.

Schedule a Professional Mold Inspection

Even if you don’t see visible signs of mold, a professional inspection from a licensed mold remediation company like Green Tree Environmental can uncover hidden problems before they spread.

When to Call a Mold Remediation Professional

If you suspect mold in your home this winter, don’t wait until spring. Green Tree Environmental is fully licensed under New York State Article 32, and we offer:

1. Thorough mold assessments and testing
2. Safe, certified mold remediation services
3. Moisture control and prevention strategies
4. Basement waterproofing and attic mold solutions

Learn why professional mold remediation is more effective than DIY mold removal.