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How to Insulate a Crawl Space (Step By Step)

How to Insulate a Crawl Space (Step By Step)
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Your crawl space is something that you want to take care of. If you don’t handle your crawl space properly, it can wind up causing problems for your home.

Some people choose to insulate their crawl spaces. This can be a good idea, but you might not know how to go about doing this.

Read on to learn how to insulate a crawl space. This will tell you everything that you need to know to get started.

You’ll also learn a bit about the benefits of insulating your crawl space. If you’re on the fence about doing this, it might help you to make the decision to move forward.

Do You Need to Insulate a Crawl Space?

Whether you need to insulate a crawl space or not depends on the situation. In some areas, it’ll be required for you to insulate the crawl space.

You need to make sure that you’re following local building codes to a tee. If the local rules in your area say that your crawl space needs to be insulated, you must make sure that it’s done right.

So look into local laws to see whether it’s required for you to insulate the crawl space section of your home. Even if it isn’t required for you to do so, it’s likely the best course of action.

You see, crawl spaces aren’t very energy efficient when they have no insulation. It’ll cause you to lose a lot of heat during the winter, and cold air will escape during the summer when you’re using air conditioning, too.

A lack of insulation in the crawl space could cause many problems over the years. It’ll lead to higher monthly energy bills and it could cause damage to your home.

Freezing Pipes

One of the most important reasons to insulate your crawl space is to avoid issues with freezing pipes. If you live in a cold climate, the weather is going to dip below 32 degrees Fahrenheit in the winter sometimes.

When the temperature outside is very cold, it’s possible that your pipes might start to freeze up. You don’t want your plumbing to freeze because the pipes could wind up bursting.

This will make a huge mess and it’ll be expensive to fix the problem. You can keep the pipes from freezing by ensuring that your crawl space is insulated properly.

This is just another important reason why you should insulate the crawl space area. Even if it isn’t required by law where you live, it’s in your best interest to insulate the crawl space.

How Much Insulation Do I Need in My Crawl Space?

How much insulation you need in the crawl space under your home depends on the climate. In warm climates, three and a half inches of insulation will be sufficient.

Colder climates are going to require more insulation than this. You might need between six inches and eight inches of insulation if you live in a cold area of the world.

It’s also important to choose the right type of insulation. Typically, you’ll combine insulation with a vapor barrier to protect your home from moisture issues.

As long as the insulation fits tightly, you should be able to do a good job protecting your home. You’ll save money on energy bills and it’ll be simpler to keep your home warm even when it’s cold outside.

Insulating Your Crawl Space

There are several things that you need to do when insulating your crawl space. It’s also important to do more than just install insulation.

You want to protect your home from moisture and other issues. Doing this right should make it easier to keep your crawl space maintained.

Below, you’ll get information about what you need to do to insulate the crawl space. Don’t skip any steps and you should be able to get the job done right.

If you’re not confident that you can handle this yourself, it’s fine to hire professionals. Most people choose to hire workers to do jobs such as this, but you can do it yourself if you have the necessary time, materials, and knowledge.

1 – Start by Preparing the Ground

It’s best to start by preparing the ground. You want to clear any debris that is present on the ground in the crawl space area.

This means getting rid of any leaves, twigs, and other stuff that might have blown into the crawl space through the vents. If there’s any construction debris, that will need to be removed as well.

Once everything is clear, do your best to even out the dirt. You want the dirt to be as even as possible throughout the crawl space.

This might involve going over the dirt with a small rake or filling in holes with extra dirt. If all is well, you can move on.

There can’t be any issues with standing water. If you have standing water in the crawl space, this problem needs to be solved before installing the insulation.

2 – Install a Vapor Barrier

You should install a vapor barrier to protect your crawl space from moisture. Crawl spaces commonly have issues with standing water, excessive moisture, and other things.

The moisture can lead to mold and mildew growing in the crawl space. This can make you and your family sick.

Standing water can damage the foundation of your home and rot your floors. A vapor barrier keeps this from happening, and it’s incredibly easy to install.

You simply need a 6-mil plastic sheeting layer to cover the ground. Make sure that the sheets cover everywhere and allow the sheets to overlap by about a foot to be safe.

The plastic sheeting needs to run all the way to the walls for this vapor barrier to truly work. It’s good to tape the seams in the sheets together so everything will stay in place.

Buying the plastic sheeting won’t cost much at all. It’s more than worth it to install a vapor barrier in your crawl space.

If you choose not to do this, it’ll be a dangerous move. You’ll be far more likely to experience issues with water damage and mold.

3 – Install Insulation Under the Floor

Now it’s time to install insulation under the floor. How much insulation you’ll need to install will depend on where you live.

You need to install more insulation when you live in a cold climate. So if you live in the Northern portions of the United States, it’s likely that you’ll need six to eight inches of insulation.

If you’re living in the Southeastern United States, you’ll be fine with three and a half or four inches of insulation. You can always look for specific recommendations based on your area.

The best type of insulation to use in your crawl space area will be either fiberglass insulation rolls or batts. These types of insulation are rather affordable and they’re easy to install even if you’re a novice.

You want to install the insulation between the floor joist in the crawl space. The insulation should be installed with the paper barrier facing up toward your home.

The insulation must fit tightly between the joists. You hold the insulation in place using support wires.

Some people even use chicken wire to hold the insulation in place. It can be stapled directly to the joists, but this method isn’t necessarily better than using support wires.

4 – Enclose the Foundation

Enclosing the foundation is another important step. If your foundation isn’t enclosed, it’s going to be hard to get decent results when insulating the crawl space.

The crawl space can be enclosed by filling the space between the exterior piers. You need to build brick walls or use concrete blocks to fill the space.

This will take a bit of effort, but it’s not difficult to get the job done. Laying bricks and using mortar to keep them in place is a common method for enclosing a crawl space foundation.

There will need to be vents placed in the crawl space walls that will allow you to access the space. You need to be able to enter the crawl space to do maintenance.

Ensure that the vents are the correct size that is required in your area. Different standards may exist depending on where you live.

You should have one square foot of vent space for every one hundred and fifty feet of crawl space. Ventilation is important and you should never have too few vents.

5 – Consider Insulating the Walls

Insulating the walls can be a helpful way to further protect your home. Some even choose to insulate the walls rather than the ceiling of the crawl space.

However, there are those who say that doing both is a great idea. You can insulate the walls (assuming that your crawl space is enclosed) using a rigid board.

The boards can be connected to the wall using either fasteners or some type of adhesive. Either option will work just fine, but be sure to install everything properly.

Make sure that the insulation is secure and that it fits tightly. This will allow you to get the best experience.

Should You Do the Work Yourself?

Don’t do the work yourself if you don’t feel like you can handle it. Not everyone is going to be comfortable doing this type of work.

Perhaps you don’t have a lot of time to take on projects such as this. If you’re someone who works more than forty hours per week, it might be easier for you to hire someone else to insulate your crawl space.

Also, you might have issues with doing the work if you don’t have experience. You want to make sure that the job is done right.

The important thing is to ensure that the insulation is installed properly. You likely could do the job yourself if you have the time to put into it, but it’s up to you to decide how to proceed.

There are many local companies that you can call that will be ready to help you out. They can assist you by installing a vapor barrier, insulating your crawl space, and enclosing the crawl space.

You can get many issues handled by calling experts. Of course, this will cost you a fair bit of cash.

If you choose to hire someone to do the work, you must be prepared to spend a bit more money. It’s generally possible to get a good deal on jobs such as this, but it’ll still be more expensive than buying the materials and doing the work yourself.

Final Thoughts

Now you should have a much better understanding of how to insulate your crawl space. Crawl spaces really do need to be insulated.

If you don’t insulate the crawl space, your energy bills are going to be much higher than they should be. You’ll lose so much heat during the winter that it’ll be upsetting.

It’s best to insulate your crawl space and install a vapor barrier at the same time. This will protect your home from moisture problems while also making everything that much more energy efficient.

You can’t insulate the crawl space if you have problems with standing water. So you might need to solve some issues before moving forward.

If all is good to go, then start by installing a vapor barrier. Lay down a 6-mil plastic barrier sheet and ensure that the entire ground area is covered properly.

After this, you can install the insulation underneath the flooring. You hold it in place with wires and make sure that it fits tightly.

Some people also choose to insulate the walls by installing rigid boards. The boards are held against the walls using either adhesive or fasteners.

This is a job that you can do yourself if you have the time. However, not everybody wants to do jobs such as this.

If you don’t like working in tight spaces, doing work in the crawl space might make you nervous. It could be better to call in professionals if you lack the time or if you just don’t feel confident doing the job yourself.

Just make sure to get your crawl space insulated soon. It’s truly the best thing you can do to protect your home when you have a crawl space foundation.

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