Fiberglass vs. Spray Foam Insulation: Which is More Effective?

With home performance energy efficiency standards becoming higher than ever, competition between different types of insulation is stronger than it has been in the past. While many homeowners may think of insulation primarily for staying warm in the winter, proper insulation also saves on summer cooling costs. While fiberglass batts are still the insulation of choice for builders, spray foam insulation has posed a serious threat to batt insulation’s dominance. However, recently builders seem to be leaning back towards batts as their primary choice. So is one type significantly more effective than the other?

According to Pro Sales Magazine, there has been some extensive testing done with the two types of insulation. The findings suggest that fiberglass batts can be as effective as spray foam. Also, they provide statistics on the drop of using spray foam vs. fiberglass batts by builders. The bottom line appears to be that either is effective, if it is installed with best practices. Whether builders out in the real world are using such best practices is the unknown variable.

Our spray foam insulation installers have all the necessary safety gear and are trained in best practices, to ensure the best results. (Image © National Lumber & Pro Insulators)

Spray foam insulation certainly does have its benefits in certain specific construction conditions. Like with any insulation, proper installation of spray foam is key to maximize air tightness. Some tests have actually found that spray foam, even with voids, can still perform better than fiberglass at extremely cold temperatures. Spray foam also shows significantly lowered air leakage under extreme conditions. Other arguments in favor of spray foam are that it’s more environmentally friendly and better for those with allergies. It also doesn’t make a good home for pests. Are these benefits worth the added cost over using fiberglass batts instead?

It appears that the economic downturn was a major factor for builders moving back to the use of fiberglass batts as a cost-saving measure. This is because they can install them more easily with their own crews rather than requiring the special equipment and training for spray foam. In areas such as typical exterior walls, with proper air sealing practices, fiberglass will certainly perform just as well as foam. However, the detriment to fiberglass insulation is when the air sealing is not done correctly, allowing air to enter the cavities and pass through the fiberglass, effectively robbing its insulating value. Fiberglass is much less expensive compared to the foam product, even after the builder adds the extra expense of the air sealing products and labor to install with the appropriate fiberglass products.

The benefit to both contractors and their clients is that National Lumber provides the quality materials they need to do the job, or Pro Insulators can provide expert teams to install insulation quickly and thoroughly with best practices using either fiberglass batts or spray foam. Hiring that expertise saves time for the builder’s crew and they move onto the next step of the building process sooner. If their high-end clients want to know they are getting the best value in their insulation, then professional best practices can provide that with either product.

What it comes down to with either type of insulation is that the quality of the installation and air sealing are key. Pro Insulators can tell you which type will perform better for a particular project. Also, it’s important that the installer be up to date with the latest energy codes, which today are always evolving. Pro Insulators always stays on top of these codes. Both types of insulation, properly installed, can meet these codes. Simply put, the choice really is the preferred material.

Just as you subcontract other specialized portions of every project, make Pro Insulators part of your team for expert results that benefit your profits. We all know that time is money, and getting the insulation installed faster by our experienced crews means that your building crew gets on to the next stage of the project faster. In addition, if a regular building crew makes mistakes installing the insulation, that will lead to failed insulation inspections. When such work has to be done over, it increases costs. The work will be done right the first time with guaranteed insulation installation by Pro Insulators. When word gets out that your homes are more energy efficient because the insulation was done expertly, word of mouth reputation for your company will grow. It’s good for the builder and good for the homeowner having Pro Insulators do the job.

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