Are Attic Baffles Necessary?

If you have a home with exterior soffit vents, you will almost certainly want to consider having attic baffles installed. When they are installed, they have a huge number of benefits.

So, what are attic baffles? What purpose do they have? More importantly, what is the benefit of having attic baffles installed? All of your questions will be answered on this page.

Hopefully, by the end of it, you will realize that attic baffles are necessary for owners of soffit roofs.

What are Attic Baffles?

Attic baffles are installed in homes that have a roof with soffit vents.

An attic baffle is a small chute, typically made from plastic, cardboard, or foam.

The attic baffle’s purpose is to allow air to flow from the vent and throughout the attic. When installed correctly, an attic baffle will help to ensure consistent airflow. This can help to combat problems such as mold and damage to attic insulation. 

What is the Purpose of Attic Baffles?

When installed, the attic baffles’ job is to take the air from the soffit vents and guide it throughout the attic space. 

This airflow helps ‘refresh’ the air in the attic, i.e., it will help remove the stale air floating about. This can help reduce moisture in the air, and it can also help ensure that the attic temperature is better controlled.

Benefits of Attic Baffles

The main benefit of attic baffles is to ensure that there is proper airflow in the attic.

  • Proper airflow helps to prevent mold from growing in the attic. This, of course, is important. After all, many of us have some of our possessions stored in the attic, and we do not want them to become mold-infested. We would have no choice but to trash them. 
  • Attic baffles also help to reduce moisture in the air. Moisture is a big contributor to mold. However, it is also a huge contributor to wood rot. Wood rot will destroy your rafters if it is allowed to get out of hand. This is going to be a rather costly repair job.
  • Attic baffles will also help to ensure that the temperature in the roof is a lot more consistent. This can help when it comes to energy bills. Remember, if there is a lot of heat up there in the roof, this can cause the rest of the home to heat up. This means that the air conditioner may need to be cranked up an extra level, increasing energy costs.
  • Attic baffles can also help to protect roof insulation. If you have soffit vents, then air is going to be flowing into the roof. If there are no attic baffles to guide airflow, then that air will be hitting the insulation. Over time, this will reduce the insulation’s efficiency, resulting in it needing to be replaced far more often. Attic baffles help to guide air away from the air insulation. Again, helping to ensure far more consistent temperatures in your home.
  • Attic baffles will also help to prevent the soffit vents from being clogged by the insulation. This, of course, will help ensure that air is flowing into the attic as smoothly as possible.

For the most part, attic baffles should be fairly easy and affordable to store too. If you install the attic baffles yourself, then you may be able to enjoy all of these benefits for no more than $100-$200, depending on whether you have the tools that you need for installation already.

Types of attic baffles

Attic baffles tend to come in two sizes. You have attic baffles designed to fit rafters that are 16-inches apart and rafters that are 24-inches apart. To ensure that the attic baffles can do their job, you must select the correct size.

Attic baffles are also available in a variety of different materials. This includes:

  • Foam
  • Cardboard
  • Plastic

Each of these materials has its pros and cons. Therefore, you must choose the correct material for your situation. This will typically be either foam or cardboard baffles.

Cardboard vs. Foam Baffles – Which One Should you Choose

Perhaps the major advantage that cardboard baffles have over foam baffles is that it is a far cheaper material. This means that installation costs are going to be much lower.

The downside of cardboard baffles, however, is that they are weak. They are especially weak if you live in an area of high humidity.

On the most humid days, the cardboard baffles will start to absorb humidity from the air that flows through them. Over time, this will cause the cardboard baffles to break down. They are going to need to be replaced far more frequently. 

If you can afford them, then we suggest that you try to opt for foam baffles. While they are more expensive, they will tend to last longer in almost all conditions. 

How Many Attic Vent Baffles do I Need?

It depends on the number of rafters you need, plus the size of your attic.

You will need to have at least one attic vent baffle between each of the rafters.

Because attic vent baffles tend to be manufactured in 4-foot lengths, you will likely need multiple baffles between each rafter.

Do I Need Baffles in Every Rafter?

To ensure that the baffles work correctly, there should be one placed between every rafter.

How Long should Attic Baffles Be?

Attic baffles will be around 4-feet long. However, they can be trimmed down if the baffle is a little bit too long for the attic. 

Do I Need Baffles If no Soffit Vents?

If you do not have soffit vents, then there is no need to have baffles. 

Without soffit vents, there will be no air flowing into that attic, and therefore the baffles would be useless. Remember, the whole purpose of attic baffles is to help with the attic’s airflow and venting. Without that air, they don’t have a job to do.

How Much Does it Cost to Install Attic Baffles?

If you are installing the attic baffles yourself, you can expect to pay between 75-cents and $2.00 per foot of attic baffle.

If you are hiring a professional installer to install the attic baffles for you, you can expect the cost to be somewhere around the $300-$500 mark, although this depends on how much work needs to be carried out. Any installer will give you a quote before they start the work.

How to Install Attic Baffles

While installing attic baffles is a reasonably simple process, it would always be wise to call a roofing expert where possible.

‘The cost of a roofing expert isn’t that high for baffle installation, and you can be sure that it will be carried out properly. However, if you insist on installing attic baffles yourself, then the process should be fairly simple with some basic tools.

You will need at least two people to complete this job. 

Tools; Materials Required

The installation of roof baffles will require:

  • Measuring tape
  • Heavy-duty staple gun
  • Knife or saw, depending on the baffle material that you are using.
  • Enough baffles to fill the rafter channels
  • Spray insulation foam
  • Caulk

Select the correct baffle size

Your first job will be to measure the gap between the rafters. You will need to choose the correct baffle size. This will typically be 16-inches or 24-inches. However, do bear in mind that there may be other sizes out there.

Clean around the soffit vent

If there is insulation covering the soffit vent, then make sure that it has been removed. Before you install the attic baffles, there should be absolutely nothing restricting the airflow from the vent. If there is, it will cause issues later on.

Position your first baffle

Once you are sure that the soffit vent is completely cleared of any obstruction, you can put your first baffle into place.

You will want to position your baffle in such a way that the air flowing in from the soffit vent will flow into the baffle. This means that the soffit vent will need to be covered by the baffle.

Securing the first baffle

You will now need to position the baffle so that it covers the vent while following the roof’s angle, i.e., it needs to be pressed against the roof. 

Somebody will need to hold the baffle in position while the other person uses the heavy-duty staple gun to secure the baffle in place.

Installing the next baffles

You will then need to overlap the next baffle with the baffle that you installed already. Again, stapling it into place. There should not be a gap between the baffles. If there is, air will be able to escape, which ruins the purpose of having baffles in the first place.

Keep overlapping these baffles until you reach the top of the roof. How many baffles are needed will be dependent on how large your roof is.

Remember, you may need to cut down the last baffle. You can use your roof or saw for this. Make sure that it is appropriately measured.

Repeat the process

You will now need to repeat the process for each soffit vent. Generally speaking, there will be one placed between each rafter.

If you have more than two people working on the job, you will probably be able to install attic baffles over different soffit vents at the same time.

Sealing the baffles

Once all of the baffles are in place, you will need to seal them up. This will ensure that the air is flowing nowhere other than into the baffles and then out at the roof peak.

First, you will need to use your foam insulation to cover completely cover the gaps in the area where the baffle meets the air vent.

You will then use your caulk along the sides of the roof baffle. While you can use insulation foam for this, too, it will probably be a bit too expensive for this task. It doesn’t have that much extra benefit.

You will also need to place caulk along each of the areas where the roof baffles overlapped.

Attic Baffle Alternatives

Due to the low cost of having proper attic baffles installed, nobody has put that much effort into coming up with attic baffle alternatives. This is because many of the attic baffle alternatives probably won’t be as effective once installed, and quite often, the installation will require a lot more work.

People have made their attic baffles out of the following materials:

  • MDF
  • Plastic sheets
  • Styrofoam sheets
  • House wrap

However, do bear in mind that you will need to shape these properly. That is where the issue is. You w9ill probably end up spending a ton of time shaping the attic baffle alternative for the sake of saving a few dollars.

Remember, since none of these alternatives will have been designed to act as baffles, they probably won’t last as long either.

So, not only are they going to be a whole lot more troublesome to install, but you will have to be going through that installation process a lot more frequently than you would with proper baffles for the attic.


While you do not need attic baffles, it is always wise to have them installed if you have soffit vents. They are vital for helping to ensure consistent airflow throughout the attic. This, in turn, can result in a reduction of mold and stale air.

Compared to the benefits that you get from installing the attic baffles, the cost of having them installed is not that high. Therefore, while they are not strictly necessary, they are always worth having installed anyway, assuming that you have soffit vents.