What Is the “Stack Effect?”: Addressing Upstairs Heat and Mold
Wondering why your upstairs is always so much hotter than downstairs? That’s the because of the “Stack Effect.”
Does the Stack Effect cause other problems (like mold) in my home? Sadly, yes.
Is there anything you can do to about it? Yes!
In this article, we answer all your questions about the “Stack Effect” and what you can do to reduce its impact on your home and health.
What Is The Stack Effect?
The Stack Effect is what happens when cold air rises through your home, increasing in density and temperature with each subsequent level, and creates a continuous cycle of airflow from bottom to top.
In your home, the Stack Effect works like this:
- Warm air comes enters the crawl space below your home.
- The air goes up through your floor, seeping through access hatches, duct chases holes around wires and pipes, and joints in floorboards.
- The air rises to higher levels, increasing in temperature.
- As it escapes out of the uppermost level of your home, it creates negative pressure at the base of your home, drawing more air into your crawl space.
- Rinse. Repeat.
While you’ll definitely feel the heat in the upper levels of your house during the summer, the Stack Effect is actually the most active when the difference between the temperature inside your home is significantly warmer than it is outside (ie. in the winter months).
Why The Stack Effect Is a Problem
The Stack Effect highlights two basic issues with your home. Both of these issues have to do with your crawl space.
1. Mold and Bad Air Quality
Building scientists say that up to 50% of the air you breathe on the first floor came from your crawl space. If there’s moisture and mold in your crawl space, your breathing it throughout your home.
If your crawl space is taking in moisture with the air, mold spores will come up into the upper levels of your home with it. This is usually how you get mold in your attic.
2. Higher Energy Bills
With air flowing up into your home from your crawl space, your HVAC system is overworking itself to keep the interior at a set temperature. This naturally means higher energy bills that can increase by up to 25%.
Air in your crawl space may be too cold, and your upper floors may be too warm. That’s a big job for one HVAC system, and it’s not always up to the task.
What to Do About It: Crawl Space Encapsulation
According to the EPA, “If mold is a problem in your home, you must clean up the mold and eliminate the sources of moisture. Molds have the potential to cause health problems. Molds produce allergens (substances that can cause allergic reactions) and irritants.” The best thing you can do to put a stop to the Stack Effect is to get your crawl space fully encapsulated.
Encapsulation seals off your crawl space from outside air and moisture, putting a hard stop to mold growth and needlessly high energy bills. To learn more about it, check out our Crawl Space Encapsulation page.
Put a Stop to Stacking Bills, Heat, and Mold. Call Tar Heel Basement Systems Today!
If you live in North Carolina, call Tar Heel Basement Systems today. We’re the leading crawl space repair experts near you with decades of experience fighting the root causes of the Stack Effect.
We’ll get you on your way to a smarter, healthier home with a free inspection and estimate. Reach out today to schedule yours!
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