Spray Foam vs. Traditional Insulation: Which Is Right for You?

Your insulation helps keep you comfortable while improving your home's energy efficiency. Essentially, insulation is designed to act as a barrier against "heat transfer", for example, between the warm air inside your home and the cold air outside during the winter months.

But which type of insulation is best? In this post, we're going to compare two popular choices: spray foam and traditional fiberglass insulation.

What is Spray Foam Insulation?

Spray foam, or spray polyurethane foam, is a type of insulation that is sprayed onto the desired surface while in liquid form. Once it's applied, the foam expands and hardens, sealing all gaps and cracks to form an airtight insulating barrier.

There are two main types of spray foam insulation:

  • Open-Cell Spray Foam - Open-cell spray foam is lighter and less dense and is ideal for interior applications. It is less expensive but has less thermal resistance than closed-cell spray foam.

  • Closed-Cell Spray Foam - Closed-cell spray foam is dense, resistant to water and moisture, and can be used to reinforce a structure, making it suitable for exterior applications or attics, crawl spaces, and basements.

Worker insulating spray foam

What is Fiberglass Insulation?

Traditional fiberglass insulation is the pink batting-type insulation that you are probably familiar with as it's one of the most widely used insulation materials. Fiberglass insulation is made from recycled glass that's melted down and spun into fine fibers. The glass fibers trap millions of tiny air pockets, giving fiberglass its insulating properties. Fiberglass insulation is typically pre-cut into batts or rolled sections that fit between studs, joists, and beams. Fiberglass is also available as "loose-fill" which is blown into place to fit irregular shapes or areas.

When choosing between spray foam and traditional fiberglass insulation, it's important to consider several factors. Let's compare:

Comparison between spray foam and fiberglass insulation

Initial Cost

Spray foam is generally more expensive to install than fiberglass insulation. The cost of your insulation project can vary depending on the thickness of the insulation, the location in your home where your insulation will be installed, the labor costs, and whether you are insulating a new build or reinsulating your current home.

Generally, closed-cell spray foam is the most expensive, costing around $1.00 to $1.50 per board foot (1 board foot = 1 square foot with 1-inch thickness), while open-cell spray foam costs around $0.44 to $0.65 per board foot. Fiberglass is the most affordable option initially, starting at around $0.30 per board foot.

Thermal Resistance (R-Value)

One of the main considerations when choosing an insulation is the R-value. The R-value measures how much resistance the insulation has to heat flow. A higher R-value means more thermal resistance, and the more effective a material is at insulating.

Generally, spray foam insulation is more effective at stopping heat transfer than fiberglass. Closed-cell spray foam has a very high R-value at R-6 to R-7 per inch, whereas open-cell spray foam is around R-3.5 per inch. Traditional fiberglass has an R-value between R-2.5 to R-3.5 per inch.

Energy Efficiency

A well-insulated, energy-efficient home can reduce your monthly energy bills when you heat your home in winter or use your air conditioner in the summer. Because of its high R-value and ability to create an airtight seal, spray foam insulation is the most energy-efficient insulator. Although spray foam may cost more upfront than fiberglass, the long-term savings on heating and cooling bills may offset the initial investment.

Durability and Lifespan

Spray foam and fiberglass insulation can both last a long time, but spray foam is generally expected to last longer and require less maintenance.

When installed properly, spray foam insulation can last up to 100 years. Spray foam is designed to be resistant to moisture, changes in temperature, and settling with little to no maintenance requirements.

Fiberglass insulation can last 80-100 years but is usually replaced every 15-20 years as it can experience degradation over time, especially if not installed meticulously. Fiberglass is susceptible to water damage, mold and mildew, pests such as rodents and insects, and settling over time. These factors can diminish its overall effectiveness and efficiency.

Installation Process

Both spray foam insulation and traditional fiberglass require the right tools, knowledge, and skills to install properly and both pose their own set of safety hazards. For these reasons, it's recommended to hire a professional contractor to insulate your home.

Fiberglass is available in pre-cut batts or rolls that can be placed into wall studs, attic rafters, or ceiling joists. Installation is fairly straightforward, making fiberglass insulation a popular choice for DIYers. Achieving optimal performance with traditional fiberglass requires careful placement to avoid any gaps or compression that can compromise its efficiency. Fiberglass can be dangerous if inhaled and can irritate skin upon contact.

Spray foam installation is a bit more complex. The process involves mixing and spraying the product with a specialized spray foam gun. Spray foam insulation uses chemicals that can give off harmful fumes before it dries, which can irritate your skin, eyes, and lungs. It's very important to wear protective gear and follow all necessary safety precautions when applying spray foam.


Spray foam and traditional fiberglass insulation are both effective insulators. Fiberglass is an affordable option upfront, however, spray foam insulation is more durable and offers a high R-value, which could save you money on monthly bills. Great Canadian Insulation provides a variety of insulation services in Winnipeg and the surrounding areas. Contact us today for a free quote!

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How to Properly Install Spray Foam Insulation in Your Home