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Stack Effect

Impacting your home’s air quality and energy efficiency, the stack effect is something you’ll want to know more about.

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It’s pretty common for homes in Alabama and Tennessee to have crawl spaces. They have numerous benefits, such as easily accessible plumbing and wiring as well as additional storage space. However, crawl spaces have their cons too. Namely, the stack effect is the biggest issue homes with crawl spaces have. 

This phenomenon refers to the movement of air through your home. The stack effect impacts both temperature and moisture levels, leaving you with poor air quality and low energy efficiency. The latter means that your utility costs are going to skyrocket, and you’ll need to pay them with your hard-earned money. 

While home designers and builders understand the stack effect, homeowners don’t think much about it until they learn that it’s causing their high energy bills. Let’s delve into what this physical process is and how it affects your home by discussing the problems it causes as well as point out smart solutions you can employ with professional help. 

crawl space stack effect

How Does the Stack Effect Work? 

It’s not uncommon for homeowners to have a hard time figuring out how air movement and heat flow work around their homes. It can get a bit confusing at first. It also doesn’t help that some home repair pros will say that warm air rises while heat doesn’t. But wait a minute. Doesn’t the heat go up with it? 

In theory, warm air goes up because of the lack of cool air at the top. And as it rises, the pressure at the base of the building drops. This leaves you with warm air wanting to escape your home and low pressure at the bottom. Well, that’s not good. 

There are two problems with this phenomenon. The first one occurs during the winter, as the stack effect causes the heat to go up alongside warm air that’s less dense than the cold air surrounding it. On the other hand, in the summer, the heat goes down, following the cold air just like the second law of thermodynamics suggests. 

Either way, it’s bad. When you need to heat your home up, cold air will replace the heat and push it out through the gaps at the top of your home. The reverse will happen when you need to cool your home down. The more cracks in your crawl space and attic, the greater the temperature loss. This will leave you in a position to use more power to supply your heater and air conditioning. 

What Lies Behind the Stack Effect? 

Three major stack effect concerns will produce problems for both your comfort and health. Here’s what they are: 

  • Entry and exit points: The first reason why you might have a problem with energy efficiency and poor air quality are cracks and holes. Outside air will pass through entry points into your home, disrupting the pressure and forcing the hot inside air to leave through exit cracks and holes. You can address this issue with professional help by sealing the entry and exit points. 
  • Upward moving air: The stack effect is going to occur regardless of your intentions. By the laws of physics, warm air will move upwards, and cool air will replace it at the bottom. This will happen no matter what the temperature inside your home is. Warm and cool air have different densities, meaning that they’ll rearrange their positions accordingly. 

This is common if you have vents in your crawl space. Depending on the state of your vents, air will act in one of two ways. If your vents are in poor condition, the cool air in the crawl space will stay put and warm air will move up. The warm air will then go through your entire home, eventually leaving through the attic. 

  • Airborne Particles: Some studies suggest that around 50% of the air in your crawl space will eventually end up in your living area. The problem with this phenomenon is that it will bring in moisture as well as airborne particles from the crawl space that are harmful to your health. These include allergens, dust mites, mold spores, and many more microorganisms that you wouldn’t want to breathe in. 

How the Stack Effect Affects You 

The thing with the stack effect is that it doesn’t just make your home uncomfortable, but it also affects other aspects of your life. Here’s what it can cause: 

  • Health issues: The first and major concern of the stack effect is that it can cause various health problems for you and your family. The allergens, dust mites, and other microorganisms that it will bring up into your home can cause serious harm. From a runny nose to respiratory infections, health issues can vary greatly. Either way, you shouldn’t breathe in any of them.  
  • Mold and mildew infestations: Sweeping through your home, the cold air from the crawl space will bring with its tiny mold spores. They’re small enough to float through the air and go through even the tiniest of cracks and holes in your home. The way they endanger your home is by attaching to damp walls and quickly growing. Mold spores love high humidity, but they’ll settle on anything if you allow them to. 
  • High utility costs: Besides health concerns, the stack effect will affect your wallet too. A poor-quality crawl space can increase your energy cost by up to 25%. Your heater or AC system will then need to use more power to keep up with the temperature swings. But apart from that, the moisture buildup will mean you’ll need a dehumidifier as well. 
  • Costly Repairs: Unfortunately, health problems, mold infestation, and high utility costs aren’t the only three problems an open crawl space will cause you. It will also lead to unnecessary repairs that will cost you your hard-earned money. The moisture-laden air will cause wood rot, which will affect the structural integrity of your home. And if that happens, you’re likely to contact professionals to repair the damage and that means losing money. 

Encapsulating Your Crawl Space with Professional Help 

In case you’re looking to improve your situation, there’s no better way to do so than by contacting a professional crew to encapsulate your crawl space. Our Tennessee or Alabama team at AFS will provide you with a free inspection and offer solutions to keep your home safe, stable, and comfortable for years to come.

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