Comparing Insulation Materials

Comparing Insulation Materials for Ontario Construction

Choosing the right insulation is one of the most important decisions contractors and homeowners make during any building or renovation project. In Ontario, where winter temperatures regularly drop well below freezing and summer heat can be intense, proper insulation directly affects energy efficiency, comfort, and long-term building performance.

At HB BuildPro, we supply a full range of insulation materials to contractors across the Greater Toronto Area. This guide compares the most common insulation types to help you select the best option for your next project.

Fiberglass Insulation

Fiberglass remains the most widely used insulation material in Ontario residential and commercial construction. Available in batts, rolls, and loose-fill forms, fiberglass insulation offers a reliable combination of performance and affordability that has made it the industry standard for decades.

Fiberglass batt insulation typically provides R-values between R-12 and R-24 per standard stud cavity, depending on thickness. It is non-combustible, does not absorb moisture, and resists mold growth when properly installed. For contractors, fiberglass is familiar, easy to cut and fit, and readily available from suppliers throughout the GTA.

The main limitation of fiberglass insulation is its sensitivity to proper installation. Compressed, gapped, or poorly fitted batts can significantly reduce thermal performance. Air sealing must be addressed separately, as fiberglass alone does not create an air barrier.

Mineral Wool Insulation

Mineral wool, also known as rock wool or stone wool, has gained significant popularity among Ontario contractors in recent years. Made from molten rock spun into fibres, mineral wool offers several advantages over traditional fiberglass that justify its higher price point.

Mineral wool batts provide higher R-values per inch than fiberglass, typically achieving R-15 in a standard 2x4 wall cavity compared to R-12 for fiberglass. The material is denser and more rigid, making it easier to install without gaps or compression. Mineral wool is also naturally fire resistant, with a melting point exceeding 1000 degrees Celsius.

For soundproofing applications, mineral wool is the preferred choice among contractors. Its density provides superior sound absorption compared to fiberglass, making it ideal for party walls, floor assemblies, and any application where acoustic performance matters.

Spray Foam Insulation

Spray foam insulation comes in two varieties: open-cell and closed-cell. Both types expand on application to fill cavities completely, creating both a thermal barrier and an air barrier in a single application. This dual function makes spray foam particularly effective in reducing energy costs.

Closed-cell spray foam provides the highest R-value per inch of any common insulation material, typically achieving R-6 to R-7 per inch. It also adds structural rigidity to walls and provides a moisture barrier. Open-cell spray foam offers lower R-values around R-3.5 per inch but at a lower cost, and it provides excellent sound dampening.

The primary drawback of spray foam is cost. Professional installation is required, and the material itself is more expensive than fiberglass or mineral wool. However, the energy savings and air sealing benefits often make spray foam cost-effective over the building's lifetime, particularly in older homes with significant air leakage.

Rigid Foam Board Insulation

Rigid foam board insulation, available in expanded polystyrene, extruded polystyrene, and polyisocyanurate varieties, is commonly used for exterior continuous insulation, basement walls, and foundation applications. Each type offers different R-values, moisture resistance, and cost characteristics.

Extruded polystyrene, commonly known by brand names like Styrofoam, provides R-5 per inch with excellent moisture resistance, making it ideal for below-grade applications. Polyisocyanurate boards offer the highest R-value per inch among rigid foams at R-6 to R-6.5, but perform less well in cold temperatures. Expanded polystyrene is the most economical option at R-3.8 to R-4.4 per inch.

For Ontario contractors, rigid foam board is essential for meeting the continuous insulation requirements in the Ontario Building Code. Adding rigid foam to the exterior of wall assemblies helps reduce thermal bridging through studs and can significantly improve overall wall performance.

Blown-In Cellulose Insulation

Cellulose insulation is made from recycled paper products treated with fire retardants. It is blown into wall cavities and attic spaces using specialized equipment, filling gaps and voids that batt insulation might miss. Cellulose provides R-values of approximately R-3.5 per inch.

The main advantage of cellulose is its ability to conform to irregular spaces and fill around obstacles like wiring and plumbing. For retrofit insulation projects, dense-pack cellulose can be blown into existing wall cavities through small holes, making it an excellent choice for upgrading older Ontario homes without removing wall finishes.

Ontario Building Code Requirements

The Ontario Building Code sets minimum insulation requirements that vary by building type, climate zone, and assembly. For most of southern Ontario, including the Greater Toronto Area, wall assemblies in new construction must achieve minimum effective R-values that account for thermal bridging through framing members.

Current code requirements for residential construction in Zone 6, which covers most of the GTA, include minimum R-24 for above-grade walls, R-31 for ceilings below attic spaces, and R-20 for basement walls. These requirements can be met through various insulation strategies, and many builders exceed these minimums to improve energy performance and marketability.

Choosing the Right Insulation

The best insulation choice depends on several factors including the specific application, budget, performance requirements, and project timeline. Fiberglass and mineral wool batts remain the most cost-effective options for standard wood-framed walls. Spray foam excels in situations where air sealing is critical or where irregular cavities make batt installation difficult.

For basement insulation, rigid foam board is often the preferred choice due to its moisture resistance and ability to provide continuous insulation without thermal bridging. In attic spaces, blown-in cellulose or fiberglass can be applied quickly and economically to achieve high R-values.

Many successful projects use a combination of insulation types to optimize performance in different assemblies. For example, a high-performance wall might use mineral wool batts in the stud cavities with rigid foam board on the exterior for continuous insulation.

Get Expert Insulation Advice from HB BuildPro

At HB BuildPro, we carry fiberglass batts, mineral wool boards, rigid foam insulation, and insulation accessories for contractors throughout the Greater Toronto Area. Our knowledgeable team can help you select the right insulation products for your specific project requirements and ensure you meet Ontario Building Code standards.

Whether you are building new, renovating, or upgrading existing insulation, HB BuildPro provides the materials and expertise to help you deliver energy-efficient, comfortable buildings for your clients. Contact us today to discuss your insulation needs and get competitive pricing.

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