If you’re thinking about upgrading your home’s insulation, you’re already taking a big step toward improving comfort, energy efficiency, and even indoor air quality. But with so many options available, it can be tough to know which material is the right fit, especially if you live in a climate as diverse as Alameda County’s.

At Insulation Solutions, we’re often asked about the differences between spray foam and fiberglass insulation. Both are excellent choices, but they have different strengths depending on your home’s needs. If you’re weighing your options for a project, here’s what you should know about spray foam vs. fiberglass in Alameda County.

 

Understanding the Basics

First, a quick overview of both materials:

• Fiberglass Insulation: This is the traditional pink or yellow material you see in batts or rolls. It’s made of fine glass fibers and is designed to trap air, slowing the movement of heat.
• Spray Foam Insulation: Applied as a liquid that expands into a solid foam, spray foam creates an air-tight barrier. It comes in two types: open-cell (lighter and less dense) and closed-cell (denser, more moisture-resistant).

Each material offers important benefits, but depending on your goals and budget, one may fit your home better than the other.

 

Key Factors to Compare

Here’s how spray foam and fiberglass stack up in the categories that matter most:

1. Thermal Performance (R-Value)

The R-value measures insulation’s resistance to heat flow—the higher, the better.

Fiberglass typically has an R-value of about 2.2 to 2.7 per inch.

Closed-cell spray foam boasts a much higher R-value, around 6.0 to 7.0 per inch.

If you have limited space and want maximum insulating power (such as in a tight attic or wall cavity), spray foam has the advantage.

 

 

2. Air Sealing and Energy Efficiency

One of the biggest differences between the two is air sealing.

Spray foam acts as both an insulator and an air barrier, sealing cracks and gaps that traditional insulation can’t touch. According to the U.S. Department of Energy, air leaks can account for up to 30% of heating and cooling energy loss in homes.

Fiberglass, while effective at slowing heat transfer, does little to stop air movement unless combined with separate air sealing measures like caulking or weatherstripping.

In Alameda County, where microclimates vary from foggy coastal zones to hot inland areas, reducing air leaks can make a noticeable difference in indoor comfort and energy bills.

 

3. Moisture Resistance

Moisture is the enemy of any insulation material.

Closed-cell spray foam provides excellent moisture resistance and even strengthens the structure it’s applied to. It’s ideal for areas prone to dampness, like crawl spaces and coastal neighborhoods.

Fiberglass, on the other hand, can trap moisture if exposed to leaks or humidity. Wet fiberglass loses its insulating ability and can promote mold growth if not properly addressed.

If you’re insulating a space where moisture control is critical, spray foam may offer better long-term protection.

 

4. Cost

There’s no getting around it: spray foam costs more upfront than fiberglass.

However, many homeowners find that the energy savings over time offset the higher initial investment. If your budget is tight and immediate savings are a priority, fiberglass remains a very solid, cost-effective choice.

 

5. Installation Complexity

Both materials should be installed by professionals for the best results.

Spray foam requires specialized equipment and trained technicians to apply safely and effectively.

Fiberglass installation is less complex but must still be handled carefully to avoid gaps, compression, and poor fit, which can all reduce its performance.

At Insulation Solutions, our team is trained and certified to install both types of insulation, ensuring you get the full benefit of your investment.

 

What’s Best for Your Alameda County Home?

Ultimately, the right insulation depends on your specific situation. 

Choose spray foam if you:

• Want maximum energy efficiency and air sealing
• Have a tight attic, crawl space, or difficult-to-reach areas
• Are willing to invest more upfront for long-term savings
• Need enhanced moisture protection

Choose fiberglass if you:

• Need a budget-friendly option
• Are insulating a large, accessible area like a standard attic
• Plan to combine insulation with other air sealing methods

Each home is unique, and factors like your existing insulation, energy goals, and budget will help determine the best choice.

 

Let’s Find the Right Fit for You

Choosing between spray foam and fiberglass isn’t always easy, but you don’t have to do it alone. At Insulation Solutions, we specialize in helping Alameda County homeowners make smart, informed decisions about their insulation needs.

We’ll assess your home, listen to your goals, and recommend the best solution for your comfort, safety, and long-term energy savings.

Ready to upgrade your home’s insulation?  Call us today at 888-532-4726 or visit insulationsolutionsusa.com to schedule your free consultation.