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Crawl Space vs. Slab (The Key Differences to Know)

Crawl Space vs. Slab (The Key Differences to Know)
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Picking a foundation style for your new home is an important thing. You need to figure out which is the best option based on your budget and needs.

For many, it comes down to either a crawl space or a slab foundation. Both options have their benefits, but one might be better depending on what you need.

Before moving forward, it’s best to consider all of the factors. Even if you need to make your choice soon, it’s best to take a step back and get as much information as you can.

What do you need to know about crawl space foundations vs. slab foundations? Keep reading to dig into the details so you can make an informed decision.

What to Expect With a Crawl Space Foundation

There are a number of things you need to know about choosing a crawl space as the foundation for your home. This is one of the most popular types of foundations for manufactured homes, but it’s also commonly used for standard homes.

Below, you’ll see various facts about crawl space foundations. This should help you to better understand what crawl space foundations are best suited for.

Crawl Spaces Cost a Bit More Money

The first thing to know is that crawl spaces cost a bit more money than slab foundations. On average, crawl space foundations cost between $5 and $16 per square foot.

By comparison, slab foundations generally cost between $4 and $14 per square foot. So if you’re looking for the least expensive option, it’s best to go with a slab foundation.

This doesn’t mean that crawl spaces aren’t affordable, though. You will spend thousands of dollars more constructing a crawl space foundation than you would a slab foundation, but it’s more affordable than a basement foundation.

Crawl Spaces Are Perfect for Sloped Landscapes

If you live on a sloped landscape, going with a crawl space foundation might be the best choice. Slab foundations aren’t appropriate for sloped landscapes.

You can only use slab foundations on lots that are either flat or close to flat. Sloped landscapes would require extensive excavation to be able to use a slab foundation properly.

Crawl spaces are different because you can dig a trench on one side of the lot if necessary. It’s easier to construct the foundation without having to do significant excavation.

This should be an appropriate foundation type for people who live in hilly areas. You always want to choose the foundation that is the most practical based on your landscape.

Crawl Spaces Require Maintenance

Crawl spaces require maintenance. If you don’t take care of a crawl space it can wind up experiencing structural issues.

Those who live in areas with clay soil are more likely to deal with structural problems. So it’s important to inspect your crawl space and have repairs done as necessary.

Also, you must protect your crawl space from problems with mold and insects. There are many types of bugs and creatures that will infect your crawl space if the conditions are right.

Commonly, spiders, roaches, and mosquitoes will live in the crawl space area. This area can also attract snakes, rats, and bats.

You need to limit the ability of bugs and animals to get into the crawl space while maintaining proper ventilation. If you live in a humid area, there’s a chance that moisture issues will become a big problem as well.

Moisture can come up from the ground and cause water to get into the crawl space. This standing water can damage your home, but even the presence of moisture can lead to mold issues.

To prevent this from becoming a problem, it’s best to install a vapor barrier. This should keep moisture issues at bay.

Crawl Spaces Work Best in Dry Areas

Now that you know about the moisture issues that can occur in crawl spaces, it’ll make sense to hear that crawl spaces work best in dry areas. If you live in a humid area, it’s likely not wise to choose a crawl space foundation.

Crawl space foundations are going to be prone to moisture issues. Moisture comes up from the ground and it can make it easy for mold issues to pop up.

Also, standing water can become a big issue if you’re not careful. Installing a vapor barrier is something that can make a huge difference.

Take the climate where you live into account when choosing between a concrete slab foundation and a crawl space. Where you live might make all the difference.

Crawl Spaces Give You More Reconstruction Options

One convenient aspect of choosing a crawl space foundation is that it gives you greater reconstruction options. You might choose to remodel your home and change various aspects of it.

For example, what if you wanted to move your bathroom to the other end of the house? With a crawl space foundation, it’d be simple enough to change where the pipes are located.

If you have a concrete slab foundation, this would be much harder to do. You could still make the same changes, but it’d require a substantially bigger job to make it happen.

For some, the convenience of having a crawl space is going to win out. It does make it simpler for workers to access your pipes and vents so they can make changes for reconstruction purposes.

Crawl Spaces Can Make HVAC and Plumbing Maintenance Easier

Having a crawl space foundation makes many things simpler. You want to be able to access your vents and your pipes easily.

When you have a concrete slab foundation, the pipes are encased in concrete. To reach the pipes, you generally have to pull up floorboards or use some other type of access point.

This is a lot harder than it would be if you had a crawl space. Workers can just go into the crawl space area to access pipes and vents.

They can do maintenance work, fix leaky pipes, change things out, and do whatever else needs to be done. It’ll be far faster than it would be if they had to tear up your floors just to fix a problem.

Having either a basement foundation or a crawl space foundation will be nice. Many people prefer these types of foundations for the sake of convenience.

What to Expect With a Slab Foundation

Slab foundations are quite a bit different. These foundations are going to be great options for many people, but they have their advantages and disadvantages to consider.

Below, you’ll learn everything to expect when choosing a concrete slab foundation for your home. This should allow you to decide between a slab and a crawl space.

Slabs Are Very Cost Effective

When you want to save cash, it’s best to go with a slab foundation. Concrete slab foundations cost thousands of dollars less than crawl spaces.

Of course, the cost of the foundation won’t be the only consideration. You need to take all factors into account before making a choice.

Even so, it’s good to know that slabs are affordable foundation styles. For many, this will be the ideal choice.

Slabs Don’t Take Long to Construct

Another reason why many people choose to go with slab foundations is that they don’t take long to construct. A professional crew can get a slab foundation ready in a short amount of time.

By comparison, a crawl space foundation will take a lot more effort to construct. A crew will need to spend many more hours getting a crawl space foundation ready.

Making a crawl space foundation is more complex overall. A slab foundation is very straightforward.

Slabs Don’t Require Much Maintenance

One of the greatest aspects of going with a slab foundation is that they don’t require a lot of maintenance. You don’t need to worry about there being various issues with the foundation so long as it is constructed properly.

With crawl spaces, you have to worry about potential structural issues as well as moisture problems. Even mold can become a serious concern.

There won’t be any worries about mold or bugs coming in through the slab. So having a slab foundation does make your life simpler in some ways if you’re able to use one for your home.

Slabs Offer Greater Energy Efficiency

Energy efficiency is something that you should keep in mind when choosing a foundation. You want to go with a foundation that will keep your energy bills low.

Sadly, crawl space foundations are known to have energy efficiency issues. You’ll likely need to insulate the crawl space to keep it from causing you to have higher heating and cooling bills.

Slabs are different because they’re very energy efficient overall. You won’t lose heat because there isn’t a void beneath your home where the heat can escape the house.

Don’t let this make you think that you can’t make a crawl space energy efficient. It just involves taking extra steps.

Slab foundations are simply more energy efficient right away. So they can be better for your monthly bills without having to make an investment to improve things.

Slab Foundations Don’t Work Well in Cold Areas

Do you live in an area that gets very cold during the winter? If so, you likely shouldn’t go with a slab foundation.

Slab foundations aren’t good choices for colder climates. As soil freezes, it’ll expand and put pressure on the foundation.

This can lead to cracks forming in the foundation or it might even cause the foundation to shift. You need the foundation to be stable, and that means the footings should be below the point where the ground freezes in your area.

In cold areas, you might have to go quite deep. This is why crawl space foundations or basement foundations are common in colder regions.

Slab foundations are common in warm climates such as those seen in the southeastern United States. A slab foundation will be more practical in Florida than it would in a state such as Michigan.

The Potential for Tree Roots to Damage Slab Foundations

It’s best not to plant trees too close to your home when you have a slab foundation. Sometimes tree roots will grow out and come into contact with the foundation.

The tree roots are strong enough that they can damage the foundation. So you’re supposed to keep planted trees fairly far away from the house when utilizing a slab.

Usually, experts recommend keeping trees fifty feet away from your home. It might be wise to keep the trees further away than that just to be safe.

Is Crawl Space or Slab Better?

Whether a crawl space or a slab foundation is better comes down to what you need. Keep in mind that crawl spaces won’t be practical when you’re living in a humid area.

Likewise, it’s not good to use a concrete slab foundation when living in a cold region of the world. So you need to consider which option is appropriate based on where you live.

If you live on a sloped landscape, it’s better to have a crawl space foundation. Slabs aren’t known for working well on sloped plots of land.

Slabs don’t work well in areas that are prone to earthquakes either. Keep all of this information in mind and then decide which choice is appropriate.

If both options are doable in your area, it comes down to preference. Slab foundations generally need less maintenance and they will cost less money.

Constructing a slab foundation is much faster than constructing a crawl space, too. You might need to insulate a crawl space, and it’s likely going to require you to spend money on a vapor barrier as well.

When looking for the most affordable choice, it’s easy to see why so many people choose concrete slab foundations. However, it can be nice to have access to your pipes by entering the crawl space.

Crawl spaces make it easy to do reconstruction projects. You can change the position of your pipes and do many other things that would be tough or impossible to do with a slab foundation.

There are benefits and disadvantages on both sides to consider. Now you just have to make your final choice.

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