Did you know your attic could be driving up your energy bills year-round? The culprit might be the stack effect, a natural airflow phenomenon that silently works against your comfort and your HVAC system. At Perma-Seal, we help homeowners across Chicagoland identify and combat this issue with effective insulation and air sealing solutions.
What Is the Stack Effect?
The stack effect refers to the vertical movement of air within your home caused by temperature differences between the indoor and outdoor environments. In colder months, warm indoor air naturally rises and escapes through gaps in your attic or roof. As it exits, cooler air is pulled in through cracks and openings at the lower levels of your home, like your basement or crawl space.
This constant cycle of heat loss and cold air infiltration makes it harder to keep your home comfortable. Your furnace works overtime. Your energy bills go up. And your indoor air becomes less healthy and more difficult to manage.
How The Stack Effect Works In The Winter
During the winter, the stack effect causes heated indoor air to rise and escape through your attic. When this happens, cold outdoor air gets drawn in at the lower parts of your home through foundation cracks, rim joists, unsealed crawl spaces, and basement windows. As a result, you feel:
- Drafts near the floor
- Uneven room temperatures
- Constant cycling of your furnace
- Higher energy bills
Improper or deteriorated attic insulation only makes the problem worse. It’s like wearing a thin hat in freezing weather—the warmth just slips away.
The Reverse Stack Effect – Summer’s Effect on Your Home
In the summer—or year-round during warm weather—the process reverses. Hot outdoor air rises and pushes into your home through your attic. At the same time, your cool, conditioned air sinks and escapes from lower levels. This is known as the reverse stack effect.
For Chicagoland homeowners relying on air conditioning, this reverse airflow can lead to:
- A/C systems that run constantly
- Hot upper floors, especially bedrooms
- Increased humidity and discomfort
- Spikes in summer energy costs
How To Prevent The Stack Effect From Making Your Home Uncomfortable
Fixing the stack effect starts with sealing the holes that allow unwanted airflow and insulating the spaces that buffer your home from extreme temperatures.
1. Improve Your Insulation
Your attic is the front line of defense. We recommend upgrading to modern, energy-efficient insulation like:
- Spray foam: excellent air barrier and high R-value
- Cellulose: eco-friendly and effective for tight spaces
- Fiberglass batts or blown-in: cost-effective and common
At Perma-Seal, we always remove old, compacted insulation before installing new material. We also include air sealing as part of our attic insulation process, because insulation without sealing leaves gaps that airflow can still exploit.
2. Air Sealing Cracks and Gaps
Before insulation can do its job, we locate and seal:
- Attic floor gaps and penetrations
- Plumbing and electrical openings
- Rim joists and top plates
- Leaky basement windows or crawl space vents
This comprehensive approach stops air from moving vertically throughout your home, reducing energy waste and improving indoor comfort.
Signs to Watch For
You might be experiencing the stack effect if:
- Your energy bills spike in summer or winter
- Your upstairs feels too warm in the summer or too cold in winter
- You feel drafts near the floor or around outlets
- Your furnace or A/C runs constantly
These symptoms aren’t just frustrating—they’re costly and can impact your home’s health and durability over time.
Why Choose Perma Seal For Insulation in Chicago
With over 45 years of serving Chicagoland homeowners, Perma-Seal offers a proven process for solving air leakage, moisture intrusion, and energy loss. Our attic insulation and air sealing solutions are designed for the Midwest climate and come backed by industry-leading warranties.
We don’t just “blow in insulation.” We:
- Remove outdated material
- Air seal critical points
- Install insulation that matches your home’s needs
- Offer guidance and evaluations tailored to your goals
Frequently Asked Questions
What is the stack effect in a house?
The stack effect is the upward movement of warm air inside a home, causing heat to escape through the attic while pulling in cold air from the lower levels. It increases energy costs and reduces comfort.
How does attic insulation reduce the stack effect?
Attic insulation slows heat transfer and, when paired with proper air sealing, blocks airflow paths that cause the stack effect. This helps maintain a consistent indoor temperature.
Can the stack effect happen in summer?
Yes—known as the reverse stack effect, it causes hot air to infiltrate your attic and forces cool air out at the bottom, driving up air conditioning costs.
Does Perma-Seal offer air sealing and insulation together?
Yes! Every attic insulation job includes professional air sealing as part of our comprehensive energy efficiency solution.
Schedule Your Free Insulation Estimate Today
Don’t let the stack effect compromise your home’s comfort and efficiency. Call Perma-Seal today to schedule a free attic evaluation. We’ll inspect your current insulation, identify leakage points, and provide a customized plan to protect your home, top to bottom. Contact Perma-Seal by clicking the button below or by calling 800-421-7325 for a free attic insulation estimate.