Open Cell vs. Closed Cell Foam: Which is Best for Your Home

May 2nd, 2022 BY First American Roofing

⚡️Insulation Fast Facts:

Why is it that so many homes install messy, inefficient fiberglass insulation when open and closed cell spray foam outperforms it consistently time and time again? 🤷

Today, we’ll find out the difference between open cell vs. closed cell foam.

And we’ll even compare the two main types of spray foam options so that you can make the best decision for your insulation needs.

man spraying wall with insulated foam: open cell vs closed cell foam

What Happens If Your Home Isn’t Properly Insulated?

So why is it that so many homes are underinsulated? Do homeowners just not know the benefits of re-insulating or adding insulation to their homes? It’s possible.

A few tell-tale signs of poor insulation include:

If you notice any of the above issues, call for a professional inspection. There’s a good chance you simply need to re-insulate your home. Then, you get to reap the benefits of having a nice, warm home free of cold spots and lower energy bills.

The Benefits of a Well-Insulated Home (With Spray Foam)

A properly insulated home can keep you warmer in the winter and cooler in the summer, translating to significant energy savings on your heating and cooling bills. In fact, insulation is one of the most cost-effective ways to improve the comfort of your home and reduce your energy consumption.

On average, homeowners who insulate their homes save anywhere from 10-40% on their heating and cooling costs. That’s a lot of money! Other benefits include:

As you can see, spray foam insulation is highly beneficial to any homeowner who chooses this route—more so than most standard options. But what is it exactly? And how does it work? Let’s dive in.

worker using spray foam for insulation: open cell vs closed cell foam

What Is Spray Foam Insulation?

Spray foam insulation is a two-component system made up of polyurethane and, more specifically, a mixture of isocyanate and polyol resin which turns it into foam. This material expands and hardens when combined and is sprayed via the applicator. This creates an insulating foam layer that fills all the tiny nooks and crannies in your home’s structure, making it airtight.

The History of Spray Foam Insulation

While the spray foam we’re familiar with was implemented widely in the 1980s, the technology behind this material has been around since at least the 1940s. Polyurethane was developed in Germany in the 1930s by chemist Otto Bayer.

Polyurethane was used as insulation in homes starting in the 50s, and with the invention of the Blendometer, spray foam insulation began widespread use in homes and other applications.

Since then, spray foam has become one of the most energy-efficient and affordable options for home insulation today. Despite this, fiberglass continues to be one of the top used insulation types.

A room sprayed with liquid insulating foam: open cell vs closed cell foam

How Does It Work?

Open and closed cell spray foam insulation work differently, but they both have the same goal: to keep your home comfortable while reducing energy costs. Spray foam specifically works by spraying into small areas of your home’s interior walls to fill even the tiniest crevasses to provide optimal insulation capabilities.

The spray foam comes out in a pliable form but quickly hardens within 5 to 60 minutes. This makes it an airtight seal, which is very important for insulation purposes. The closed cell variety of spray foam is denser and more resistant to moisture, making it better suited for exterior applications and areas with high humidity levels.

Open cell spray foam is lighter and less dense, making it better suited for interior applications with a higher risk of moisture. It also has a higher thermal conductivity, meaning it’s less effective at preventing heat transfer.

Both types of spray foam work to create an airtight seal and prevent moisture infiltration, making them valuable insulation options.

How Is It Installed?

To install spray foam insulation, you need to first ensure good ventilation or get yourself a vented mask plus PPE and a few other materials, including:

Spray foam comes in a pressurized canister where a hose is attached with a spray nozzle or gun at the end, which will fan out the spray foam, covering all the surface area you need.

The installer will need to wear a mask, safety goggles, and gloves to avoid contact with the resin. The area where insulation is being installed must be clear of all furniture, pets, plants, and anything else that may get in the way.

Once the installation is complete, you’ll need to wait 24-48 hours for the foam to completely dry before returning furniture and other items back into the space.

Worker spraying closed cell spray foam insulation: open cell vs closed cell foam

Open Cell vs. Closed Cell Foam Insulation (Pros and Cons)

While you now have a basic understanding of spray foam insulation, we can get into the differences between open cell and closed cell foam insulation. While they each have their fair share of benefits (and downfalls), one may be more suitable for your needs over the other, so weighing the pros and cons is highly beneficial.

The Difference Between Open Cell and Closed Cell Insulation

The structure of the materials and the cells are what give spray foam the name of either open or closed cell. Open cell spray foam is more flexible and softer than closed cell because it has more space between the cells—kind of like air bubbles or gaps. While this type of spray foam can be more susceptible to holding water or moisture, it can be easier to manage and fill spaces since it’s not as rigid as closed cell.

Closed cell spray foam is just the opposite, with no air or space in the cells. This rigidity is more robust, firmer, and even helps strengthen the integrity of the structure it’s insulating. That means if you insulate your attic with closed cell, the walls will be stronger and sturdier than that of open cell insulation.

✅  Open Cell Spray Foam Pros

Open Cell Spray Foam Cons

✅  Closed Cell Spray Foam Pros

Closed Cell Spray Foam Cons

Which One Is Best? Open or Closed Cell Spray Foam?

technician spraying foam insulation in attic: open cell vs closed cell foam

While each of these types has its own pros and cons, there are some shared benefits of spray foam, such as creating an excellent air barrier for your home, lowering energy costs drastically, and lasting longer than fiberglass or other insulation types. So ultimately, it will come down to a few things.

  1. Which R-value do you want or need? Some areas require a specific R-value in your home to be up to code, and in that case, you may want to invest in closed cell foam, which has a higher R-value of 7.
  2. Do you have tough-to-reach spaces in your attic or walls? Open cell spray foam can get into all those nooks and crannies that closed cell simply cannot. It’s a great flexible option.
  3. Do you want a more secure structure and stronger walls? Then closed cell is your best option. Its immense density and hardening abilities can actually strengthen anything it’s installed within.
  4. What’s your budget? While open cell is much more affordable than closed cell, it doesn’t have the same longevity or ability to insulate in extreme temperatures. So consider both when choosing which is the best investment.

Getting Your Home Properly Insulated the Right Way

No matter which type of spray foam insulation you choose, installing it correctly is the most important thing. And choosing a contractor experienced in the proper techniques is vital to ensuring your home gets the energy savings and proper insulation it needs.

For premium insulation applications, contact First American Roofing and Siding. After a thorough whole-home assessment, our team will find a solution to bring you cost savings, financial incentives, and more efficient home. Reach out today!