Insulation Examples: 8 Types for Ontario Homes

When homeowners and contractors start planning an insulation project in Ontario, the sheer number of material options can be overwhelming. Understanding real insulation examples — how each type works, where it performs best, and what the Ontario Building Code requires — is the fastest way to make a confident, cost-effective decision.

Ontario's climate is unforgiving. Winters in Toronto and the broader GTA regularly drop below -15°C, and summers push past 30°C with high humidity. The insulation you choose needs to handle both extremes. This guide breaks down eight practical insulation examples by material type, application, R-value, and installed cost — so you know exactly what you're comparing.

What Counts as an Insulation Example?

Insulation refers to any material installed to slow the transfer of heat through a building assembly — walls, roofs, floors, foundations, and mechanical systems. Each insulation type works differently: some trap air in fibres, some create closed cells of gas, and some reflect radiant heat. The right choice depends on the location in the building, the target R-value, the vapour control strategy, and your budget.

R-value measures thermal resistance per unit of thickness. The higher the R-value per inch, the thinner the material can be while still meeting code minimums. Ontario Building Code (OBC) Section 9.36 sets out minimum effective thermal resistance values for different climate zones — most of the GTA falls within Climate Zone 6, which carries some of the most demanding requirements in Canada.

R-value alone doesn't tell the whole story. Air-sealing performance, vapour control, moisture resistance, and installation quality all determine how well an insulation system actually performs in a real Ontario home.

Insulation Examples: 8 Types Used in Ontario Construction

Below are the most common insulation examples you'll encounter on GTA residential and light commercial projects, from renovation retrofits to new multiplex builds.

1. Fibreglass Batt Insulation — The Most Familiar Example

Fibreglass batts are the classic insulation example most Canadians picture: pink or yellow rolls of spun glass fibre, pre-cut to fit between standard wood studs at 16" or 24" on centre. They're available in several thicknesses and densities, and they're the most widely installed insulation type in residential construction across Ontario.

• R-value: approximately R-3.7 per inch (standard density) or R-4.3 per inch (high density)
• Common applications: above-grade walls, floor assemblies, attic floors, interior partition walls
• Typical installed cost in GTA: $0.50–$1.20 per square foot depending on thickness and access
• Does NOT air-seal — requires a separate poly vapour barrier per OBC
• Does not perform well when compressed or when gaps are left around obstructions

A standard 2×6 exterior wall framed at 16" o.c. gets an R-22 batt — that hits the OBC minimum effective R-value for above-grade walls in many Ontario applications when combined with exterior continuous insulation. Fibreglass batt is a cost-effective baseline, but it demands careful installation to avoid voids and compression, both of which dramatically reduce real-world performance.

2. Mineral Wool (Rockwool) Batt Insulation — A Fire-Resistant Alternative

Mineral wool batts — commonly sold under the brand name Rockwool or Roxul — are made from basalt rock and recycled slag. They're denser and more rigid than fibreglass batts, which makes them easier to cut cleanly around electrical boxes and pipes. More importantly, they're non-combustible and melt-resistant up to 1,000°C, making them a preferred choice for fire-separation assemblies.

• R-value: approximately R-4.2 per inch (slightly better than standard fibreglass)
• Common applications: exterior walls, party walls in multiplexes, fire-separation assemblies, basement walls
• Typical installed cost in GTA: $1.00–$1.80 per square foot
• Naturally water-resistant — won't absorb moisture or support mould growth
• Provides better acoustic performance than fibreglass at the same thickness

3. Closed-Cell Spray Foam — The Highest-Performing Insulation Example

Closed-cell spray polyurethane foam (ccSPF) is the highest R-value-per-inch insulation product available for residential use. It's sprayed as a liquid that expands and hardens into a rigid, dense foam — sealing air gaps and insulating in a single application. This makes it the go-to choice for challenging locations like rim joists, crawl spaces, and unvented roof assemblies.

• R-value: R-6.0 to R-7.0 per inch — the highest of any common insulation type
• Acts as both an air barrier and a Class II vapour retarder at 2" thickness
• Common applications: rim joists, foundation walls, unvented attics, below-grade walls, shipping containers
• Typical installed cost in GTA: $3.00–$6.50 per square foot for a 2" application
• Requires professional installation with proper PPE and ventilation — off-gassing during cure is hazardous

In Ontario basement retrofits, 2" of closed-cell spray foam on the interior face of the foundation wall achieves roughly R-12 and eliminates the rim joist air leakage that accounts for a disproportionate share of heat loss in older Toronto homes. For professional closed-cell and open-cell applications, see our spray foam insulation services.

4. Open-Cell Spray Foam — A Vapour-Permeable Spray Example

Open-cell spray foam (ocSPF) uses a different chemical formulation that results in a soft, spongy material with an interconnected cell structure. It's significantly less expensive than closed-cell foam but offers a lower R-value and is vapour-permeable — which affects where it can be safely used in Ontario's cold climate.

• R-value: R-3.7 to R-4.2 per inch — comparable to high-density fibreglass batt
• Vapour-permeable (Class III retarder) — requires additional vapour control in cold climates
• Common applications: interior wall cavities for air-sealing, soundproofing partition walls, unvented attic assemblies with careful moisture analysis
• Typical installed cost in GTA: $1.50–$3.00 per square foot for a 3.5" application
• Excellent air-sealing properties — fills irregular cavities and gaps that batts cannot reach

5. Rigid Foam Board — A Continuous Insulation Example

Rigid foam board is one of the most important insulation examples for modern Ontario construction because it addresses thermal bridging — the heat loss that occurs through wood or metal studs that bypass cavity insulation. The OBC increasingly requires continuous insulation (ci) on the exterior of building envelopes, and rigid board is the standard way to deliver it.

There are three main types of rigid foam board used in Ontario:

• EPS (Expanded Polystyrene): R-3.6 to R-4.2 per inch — white, vapour-permeable, most affordable. Used under slabs, on foundation exteriors, and behind cladding.
• XPS (Extruded Polystyrene): R-5.0 per inch — blue or pink, vapour-resistant, excellent for below-grade applications. Typical installed cost: $0.40–$0.80 per board-foot.
• Polyisocyanurate (Polyiso): R-5.7 to R-6.5 per inch at room temperature — most common for roofing and commercial wall assemblies. Note: R-value decreases at cold temperatures.

6. Blown-In Fibreglass or Cellulose — The Best Attic Insulation Example

Loose-fill blown-in insulation is the standard approach for attic floors in existing Ontario homes. It fills irregularly shaped spaces, covers obstructions like ceiling strapping and pot-light boxes, and achieves very high R-values economically. Cellulose (made from recycled newsprint) and fibreglass are the two dominant products.

• Cellulose R-value: R-3.5 to R-3.8 per inch; settles slightly over time
• Blown fibreglass R-value: R-2.5 to R-4.3 per inch depending on density
• OBC minimum for attic floors in Climate Zone 6: effective R-60 in some high-performance applications; minimum code is R-31 for prescriptive compliance in most cases
• Typical installed cost in GTA: $1.00–$1.80 per square foot for an R-50 application
• Cellulose has better air-retarding properties and fire resistance due to borate treatment

For homeowners upgrading their existing attic insulation, blown-in insulation is typically the fastest and most cost-effective path to meeting or exceeding OBC minimums.

7. Batt Insulation for Basement Walls — A Common but Often Misapplied Example

Fibreglass or mineral wool batts installed in a framed interior basement wall assembly are among the most common insulation examples in Toronto renovation projects — and also among the most frequently done wrong. The key failure point: placing fibreglass batts directly against a cold concrete foundation wall creates a cold surface within the wall cavity where moisture can condense, leading to mould.

The correct approach for Ontario basements is to first apply at least 1.5" of closed-cell spray foam or rigid XPS board to the concrete, then frame and fill the stud cavity with batts. This keeps the condensation plane outside the air-permeable insulation layer. Our basement insulation team follows this sequencing on every project.

8. Duct and Mechanical Insulation — An Often-Overlooked Example

HVAC ducts running through unconditioned spaces — attics, garages, crawlspaces — lose a significant portion of the heat or cooling they carry before it reaches the living area. Duct insulation wraps are available in fibreglass duct wrap (R-4 to R-8), pre-insulated flexible duct liner, and rigid duct board. In Ontario, the National Energy Code recommends minimum R-8 on supply ducts in unconditioned spaces.

• Fibreglass duct wrap: flexible, typically R-6 to R-8, installed around rectangular or round ducts
• Elastomeric foam pipe insulation: used on refrigerant lines, plumbing, and small-diameter pipes
• Spray foam duct seal: applied at boot connections and penetrations to eliminate air bypass

Ontario Building Code Requirements for These Insulation Examples

OBC Section 9.36 (Energy Efficiency) sets out prescriptive and performance-based compliance paths for residential buildings. The prescriptive path specifies minimum effective thermal resistance values by assembly type and climate zone. For Climate Zone 6 — which includes Toronto, Mississauga, Brampton, and most of the GTA — the key minimums as of the 2020 OBC amendments include:

• Above-grade walls: effective R-24 minimum (includes thermal bridging reduction from studs)
• Attic/ceiling assemblies: effective R-50 minimum for Climate Zone 6 in the 2020 SB-12
• Basement walls (conditioned): effective R-17 minimum below-grade
• Exposed floors over unconditioned space: effective R-31 minimum
• Slab-on-grade perimeter: R-10 continuous insulation at the perimeter edge

"Effective" R-value accounts for the thermal bridging effect of framing members. A 2×6 wall cavity filled with R-22 batt has an effective R-value closer to R-17 to R-18 when you account for the studs. To reach the R-24 effective minimum, you typically need to combine cavity insulation with at least 1" of continuous exterior rigid foam.

Ontario's Supplementary Standard SB-12 provides the detailed tables contractors use to confirm compliance. Always reference the edition that was in force when your permit was issued — requirements have tightened significantly since 2012.

Choosing the Right Insulation Example for Each Location

No single insulation type works best everywhere. Here's a practical decision framework by building location:

1. Attic floor (vented attic): Blown-in cellulose or fibreglass to R-50 to R-60. Most cost-effective application for the R-value gained.
2. Above-grade exterior walls (new construction): R-22 or R-24 fibreglass/mineral wool batt + 1" to 1.5" continuous exterior rigid EPS or XPS to meet effective R-24.
3. Rim joists: 2" closed-cell spray foam. No other product air-seals and insulates this location as effectively.
4. Basement walls (retrofit): 1.5"–2" closed-cell spray foam on concrete, then frame and batt to R-12 to R-20 total assembly.
5. Interior partition walls (acoustic): Mineral wool batt (Rockwool Safe'n'Sound) or open-cell spray foam for sound attenuation.
6. Unvented cathedral ceiling or roof: Closed-cell spray foam to full R-value — no vapour barrier required above 2" application.
7. Below-grade foundation exterior (new construction): XPS rigid board, 2" to 4" continuous, protected by dimple mat before backfill.

Cost Comparison of Common Insulation Examples in the GTA

Installed costs in the GTA vary based on material, location, access difficulty, and project scale. The numbers below reflect typical 2024–2025 contractor-installed pricing for residential work. DIY installation is possible for batt products but requires careful vapour barrier detailing to meet OBC.

• Fibreglass batt (R-22 wall): $0.75–$1.20/sq ft installed
• Mineral wool batt (R-22 wall): $1.10–$1.80/sq ft installed
• Blown-in cellulose (R-50 attic): $1.20–$1.80/sq ft installed
• Blown-in fibreglass (R-50 attic): $1.00–$1.60/sq ft installed
• Closed-cell spray foam (2" rim joist/basement): $3.00–$6.50/sq ft installed
• Open-cell spray foam (3.5" wall cavity): $1.50–$3.00/sq ft installed
• XPS rigid board (2", below grade): $0.60–$1.00/sq ft material only; add labour $0.40–$0.80/sq ft
• Polyiso rigid board (2", above grade): $0.80–$1.20/sq ft material only

For most Ontario homeowners, the highest ROI investments are attic air-sealing and blown-in insulation top-ups (which reduce heating costs immediately), followed by rim joist spray foam. Above-grade wall upgrades deliver excellent long-term returns but are most cost-effective when done during a renovation that already opens the wall.

It's also worth noting that several insulation upgrades in Ontario may qualify for incentive programs under the Canada Greener Homes Grant and Enbridge's Home Efficiency Rebate program. Minimum installed R-values and pre/post energy audits are required to unlock funding — check Natural Resources Canada's current program terms before budgeting.

Common Mistakes When Applying These Insulation Examples

Even experienced renovators make avoidable errors when working with insulation. Here are the most consequential mistakes we see on GTA projects:

• Skipping air-sealing before insulating: Insulation slows conductive heat transfer; air barriers stop convective losses. Without sealing gaps first, blown-in insulation in an attic will underperform significantly.
• Compressing batt insulation: A 6" R-22 batt compressed into a 4" cavity doesn't perform at R-14 — it performs at roughly R-11. Never compress batts.
• Putting vapour barrier on both sides of a wall: In Ontario, the poly vapour barrier goes on the warm-in-winter side (interior face of studs). Adding poly on both sides traps moisture with no drying path.
• Using fibreglass batts directly on basement concrete: Without a thermal and vapour break at the concrete, fibreglass batts in a basement wall will accumulate moisture. Always use spray foam or rigid board as the first layer.
• Covering knob-and-tube wiring with insulation: This is a fire hazard and may void your home insurance. Knob-and-tube must be removed or professionally assessed before attic insulation work.
• Choosing insulation type based only on R-value: Air leakage, moisture performance, fire characteristics, and long-term stability all matter — especially in Ontario's climate.

Ready to Insulate? Konstruction Group Covers Every Example

From blown-in attic upgrades to closed-cell spray foam in basement assemblies, Konstruction Group installs every type of insulation discussed in this guide across Toronto and the GTA. Our team understands Ontario Building Code requirements, vapour control sequencing, and how to integrate insulation with framing and air barrier systems for maximum performance.

Explore our batt insulation and attic insulation services to get a quote tailored to your specific project — whether it's a new multiplex build, a basement retrofit, or a whole-home envelope upgrade.