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The Stack Effect

The stack effect is something that can wreak havoc on your home and crawl space. What do you need to know about the stack effect in your home?

Hero image of the stack effect from crawl space into the home

How the Stack Effect Affects Your Crawl Space Repair

If you’ve ever done any research into crawl spaces, chances are you’ve at least heard of the stack effect. The stack effect is one of the most prominent crawl space issues you can have, and it’s common in many crawl spaces simply due to how many homeowners have set up their crawl spaces. However, knowing about the stack effect and understanding the stack effect are two different things. Here’s everything you’ve ever wanted to know about the stack effect.

How Does the Stack Effect Work?

First and foremost, how does the stack effect work? The stack effect functions on thermodynamics. Specifically, it relies on the concept that warm air rises. Here’s a step-by-step understanding of how the stack effect can occur in your home.

  • Air Enters the Home from the Outside 

The first step of the stack effect is that air enters your crawl space from the outside. There are many ways air could come into the crawl space. Most commonly, air comes through open crawl space vents, but it can also come through the walls if you never properly waterproofed them. It can also come through loose crawl space doors.

Regardless of how it comes in, the important thing to know is that the air is coming in from the outside. This is the air that’s the same temperature and humidity levels as the outside and isn’t conditioned in any way like the rest of the air in your home. This can itself be a frustrating thing to deal with, even without the stack effect.

  • As Air Warms up, It Moves Through the Home 

Next, the air follows the laws of thermodynamics: Warm air rises. There are two pathways this can tread. The first option is that the air from the outside is already warmer than the air inside, which will cause the air to rise immediately through your home. The other option is that the air from the outside is not warmer than the air inside; if this is the case, it will warm up more the longer it stays in your home.

Either way, the air will move up throughout the home as it warms up. This is because air constantly moves into the home through the crawl space, which means it needs a way to leave the home as well. If the air is already warm, it will likely move up faster, but that’s the only real difference between the outside air being warm or cold.

  • Air Exits the Home from the Top 

The last step of the stack effect is that air exits the home from the top, typically through the attic. Even with great weatherproofing processes, there are still going to be ways for air to exit the home through the top of it. This is specifically because the entrance of air in the home requires exits as well, so air is always going to find a way out.

This will constantly repeat. The stack effect isn’t just something that happens once and never happens again. Rather, it’s a process. As long as you have an entrance for air in your crawl space, you’re going to always have air coming into your home, warming up, moving throughout the home, and then exiting through the top.

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Why Is the Stack Effect a Problem?

So what’s the problem with the stack effect? Although it might not seem like a very big problem on the surface, the truth of the matter is that the stack effect is extremely detrimental to your home’s health and wellbeing. Here are just a few of the ways that the stack effect can cause issues in your home.

  • Outside Air Entering the Home 

One of the biggest problems that you’re going to see through the stack effect is one of its most basic. Specifically, through the stack effect, it requires that you allow outside air into your home. This is a problem; even without the stack effect, you don’t want to allow air from the outside into your home if you can help it.

Outside air tends to have more pollutants and generalized issues than the inside air. You may have a dehumidifier or an air purifier in your home that keeps your air feeling fresh for yourself and your family in the home. If you’re allowing outside air into your home through the crawl space, you’re going to undo all that work.

  • Higher Air Conditioning or Heating Bills 

Chances are that the air outside your home is a different temperature than your ideal air temperature inside the home. During the summer, the outside air is probably warmer than your home’s air. During the winter, it’s probably cooler. When you allow the air inside your home without thinking of this problem, you’re going to need to condition it yourself.

When you were a kid, your mom probably scolded you if you left the front door open for too long because it would make the air conditioning or heating bills more expensive. The same concept applies here. Rather than leaving a door open, however, you’re leaving vents and grates open, and your home requires more electricity to feel comfortable.

  • Mold and Mildew Spores in the Home

Because open crawl space vents tend to cause high levels of crawl space moisture, it can cause a huge problem with mold and mildew in your crawl space. From there, you can end up with mold and mildew spores in the crawl space. The stack effect then allows those mold and mildew spores to go up into the rest of the home because they’re very small and easy to get airborne.

Mold and mildew spores in the home won’t typically be fatal, but they’re probably not going to feel very good for anyone living in the home. It’s common for mold and mildew spores in the home to cause issues with allergies, asthma, and other respiratory concerns, which means it’s important that you don’t allow it to happen.

FAQs About the Stack Effect

To understand how common the stack effect is, you need to understand why it happens. The stack effect requires openings for air near the bottom and the top of the home. Any home that has both of these requirements is at high risk of having the stack effect.

  • Openings for Air Near the Bottom

The stack effect requires an opening in the crawl space or basement. This is where the air will enter the home and begin causing problems. If your home doesn’t have a crawl space or basement, and only a well-sealed foundation, then it will be properly safeguarded from this issue.

However, not all homes are so lucky. Having a basement or crawl space is often a perk for homeowners, allowing them to use the area for storage as extra living space. If these places are properly sealed and insulated, then they will be safe from the stack effect, but any gaps will let the problem slip through. These openings may include crawl space vents, unsealed crawl space or basement doors, and ineffective basement windows.

  • Openings for Air Near the Top

The other element of the stack effect is an air opening near the top of the home. Because it’s almost impossible to completely remove any openings for air in your attic or just the top of the home, you’re typically going to have some amount of this. Bedroom doors, little gaps in your attic, and other such problems are a given. That means tackling the air openings near the bottom is your best chance to negate the stack effect. This can be done by encapsulating your basement, having better vent covers installed, or reevaluating your basement doors. Even certain waterproofing measures can help seal up your crawl space so that it doesn’t accidentally contribute to the stack effect.

It’s very important to fix whatever is leading to the stack effect in your home. Unfortunately, this isn’t an easy fix that can be resolved with a few surface-level patches. You need to address the root issue if you want to properly halt the stack effect. Otherwise, real damage can be caused. 

  • The Damage of the Stack Effect

The stack effect doesn’t create the same kind of damage as severe foundation failure or urgent flooding concerns. However, it cannot be ignored. The main troubles will include issues with high levels of moisture, significant amounts of allergens in the air, and moving mold around to different parts of your home.

As you can imagine, this is not only dangerous to the structure of your home, but also to the safety of your family. Mold can damage your walls, flooring, and support beams, leading to wood rot and other issues. Allergens can cause respiratory issues that lead to long-term sickness or disease. High levels of moisture can also result in mold, but more importantly, will mess with the temperatures of your home. This can increase your electricity bill and affect the comfort levels of everyone involved. 

  • Fixing Your Problems as Soon as Possible

If you’re experiencing the stack effect, you should take steps to stop the underlying causes. Fixing these problems early on will reduce your risk of secondary problems. The only thing worse than trying to seal up gaps in your basement or foundation is breathing in the mold while you do so. Likewise, if you wait, you may need to hire a crawl space repair expert as well as a mold expert to get your home into working order again.

The earlier you can handle the stack effect, the more likely you are to avoid related long-lasting problems. Humidity levels and allergens in the home can be very difficult to eradicate, even after you’ve fixed the stack effect. As such, while the tangible damage won’t be as severe, you’re more likely to have several issues that will escalate if you ignore the stack effect.

Getting rid of the stack effect entirely may be something that’s on your mind. The stack effect happens when air moves up from the crawl space or basement, throughout the home, and out through the top of the home. Here are the things you might need to do to stop that air movement. 

  • Crawl Space Encapsulation

The most effective way to get rid of the stack effect when you have a crawl space is through crawl space encapsulation. This can effectively block outside air from gaining access to your home. As a bonus, it can also keep out water, moisture, and help regulate the climate inside your crawl space. This can reduce energy costs, while also keeping out the classic mold, mildew, and other issues.

With crawl space encapsulation, an expert will help you close your crawl space vents, put down a crawl space vapor barrier, and potentially install something like a crawl space dehumidifier. This is a multi-step process that is best handled by an expert. Not only will they have the experience to install all of this gear effectively, but they’ll have access to the best materials, so you can have an effective, long-lasting solution. 

  • A Unique Fix

Although crawl space encapsulation is important, every crawl space requires something different. You may find the typical measures don’t work for your exact situation. You may also find that the stack effect has caused secondary issues that need fixes completely outside of what crawl space encapsulation entails.

The good news is, when you hire a local expert for the job, you can benefit from their insight and recommendations. They will be able to evaluate any unique problems your home is facing, any factors that prevent traditional solutions, and help customize a fix just for you. Talking to an expert will help you figure out what your crawl space needs.

Only an expert can help you remove the stack effect in your home entirely. Because an expert has a lot of experience with these topics, getting help from a crawl space expert will be the first step toward avoiding the stack effect if at all possible. Here’s how an expert can help.

  • Addressing All of Your Crawl Space Problems

One thing you might not even realize about your crawl space is that it’s often prone to a variety of issues. There are many problems that a crawl space can end up causing; the stack effect is simply one problem of many. Addressing all of these problems is important, but expert advice is the only way you’ll be able to address them all.

For example, your crawl space may be causing the temperatures inside your home to wildly fluctuate. It may be letting in moisture that’s resulting in high humidity levels. It could even provide access to pests, mold, or flooding issues. These are just to name a few, but rest assured, there’s a clean, cost-effective solution to all of them. 

  •  Talking to an Expert

A crawl space repair expert is always going to be your best bet when it comes to fixing problems in your crawl space, and that includes the stack effect. With a free quote and inspection, you can get a clear idea of what your crawl space is suffering from and what cost-effective solutions are available to you. Regardless of which crawl space problems you’re experiencing, you can talk to a local expert to learn more about how you can fix them. They may include cutting edge fixes like the latest vapor barriers, or simpler fixes like more effective crawl space vents. Talk to a Groundworks expert to learn more about your options.

Remove the Stack Effect from Your Home Entirely with the Help of an Expert

It’s not enough to put up barriers to the stack effect in your home. You need to get rid of the effect entirely if you want to make sure you’re getting the most out of your home’s crawl space. That’s why you need a crawl space repair expert to help you with the stack effect problems you’re having. An expert will know exactly how to fix those problems.

Talking to a crawl space repair expert should be one of the first things you do when you’re trying to get rid of the stack effect. Crawl space repair experts can help you identify the problem, create a plan to deal with it, and then put the plan into motion, and trusting Groundworks is one of the best ways to get the best fix.

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