Before comparing prices, it helps to understand the variables that drive insulation costs. Two homes on the same street can receive very different quotes depending on the following factors:

Attic Size (Square Footage)

Most insulation is priced per square foot of attic floor area. A small bungalow with a 700 sq ft attic will cost significantly less than a two-storey detached home with 1,400 sq ft of attic space. Measuring your attic accurately before requesting quotes ensures you are comparing apples to apples.

Type of Insulation Selected

Blown-in fibreglass or cellulose is the most affordable option per square foot. Spray foam costs more per square foot but delivers superior air sealing and a higher R-value per inch — making it worth the premium in many situations, particularly in older homes with significant air leakage.

Current Insulation Depth

If your attic already has some insulation, a top-up costs less than a full installation from scratch. However, if your existing insulation is water-damaged, mould-affected, or pest-contaminated, removal costs will apply before new material goes in.

Air Sealing Requirements

Air sealing — closing gaps around electrical boxes, plumbing penetrations, and attic bypasses — is a separate but critical part of any quality insulation upgrade. It adds cost but dramatically improves overall performance and is required to qualify for certain Ontario rebate programs.

Attic Accessibility

Attics with limited access hatches, low clearance, or complex roof geometry take longer to work in, which can add to labour costs. A professional assessment will flag any access challenges before work begins.

Removal of Old Insulation

If existing insulation must be removed before new material is installed, expect an additional charge for labour and disposal. Removal is typically recommended when insulation is moisture-damaged, heavily settled, pest-infested, or contains asbestos (common in homes built before 1980).

The following price ranges reflect typical installed costs for Ontario homeowners in 2026, including labour and materials. These are estimates — your specific quote may vary based on the factors outlined above. All prices are in Canadian dollars.

Blown-In Fibreglass Insulation

• Typical cost: $1.50 – $2.50 per square foot installed
• Average total for a 1,000 sq ft attic: $1,500 – $2,500
• R-value achieved: R-38 to R-60 depending on depth
• Best for: Top-ups on existing insulation, large attics, cost-sensitive projects
• Rebate eligible: Yes, when installed to minimum R-value by a registered contractor

Blown-in fibreglass is the most widely used and cost-effective attic insulation option in Ontario. It installs quickly, covers irregular spaces well, and achieves the R-50 to R-60 values recommended for our climate zone when blown to the appropriate depth. If your goal is maximum coverage at the best price, this is typically the starting point.

Blown-In Cellulose Insulation

• Typical cost: $1.75 – $2.75 per square foot installed
• Average total for a 1,000 sq ft attic: $1,750 – $2,750
• R-value achieved: R-38 to R-60 depending on depth
• Best for: Eco-conscious homeowners, homes with minor air leakage, excellent soundproofing
• Rebate eligible: Yes

Blown-in cellulose is made from recycled newsprint and treated for fire resistance and pest deterrence. It performs similarly to fibreglass blown-in but with a slightly higher density that can better fill small gaps and crevices. It is also the greener choice, with a significantly lower embodied carbon footprint than fibreglass. Pricing is comparable to fibreglass, with cellulose occasionally running slightly higher per bag due to material costs.

Open-Cell Spray Foam Insulation

• Typical cost: $1.50 – $2.00 per square foot per inch of thickness installed
• Average total for a 1,000 sq ft attic at 3.5 inches: $5,250 – $7,000
• R-value per inch: Approximately R-3.5 to R-4
• Best for: Air sealing priority, cathedral ceilings, finished attic spaces
• Rebate eligible: Varies — consult with your contractor

Open-cell spray foam expands dramatically on application, filling every gap and creating an airtight seal that blown-in insulation cannot match. However, its R-value per inch is lower than closed-cell foam, meaning you need greater thickness to achieve the same thermal performance. It is best used in combination with blown-in insulation — spray foam seals the air bypasses first, and blown-in goes on top for R-value.

Closed-Cell Spray Foam Insulation

• Typical cost: $3.00 – $5.00 per square foot per inch of thickness installed
• Average total for a 1,000 sq ft attic at 2 inches: $6,000 – $10,000
• R-value per inch: Approximately R-6 to R-7
• Best for: Roof deck application, moisture control, maximum R-value in limited space
• Rebate eligible: Varies — consult with your contractor

Closed-cell spray foam is the highest-performing insulation product available, delivering the best R-value per inch of anything on the market. It is also a vapour barrier and structural reinforcement in one. The trade-off is cost — it is the most expensive insulation option, and most Ontario attic projects use it selectively for air sealing rather than as the primary insulation layer. In situations where attic space is severely limited, closed-cell foam may be the only practical way to achieve adequate R-values.

Fibreglass Batt Insulation

• Typical cost: $0.75 – $1.50 per square foot installed
• Average total for a 1,000 sq ft attic: $750 – $1,500
• R-value: R-11 to R-38 depending on batt thickness
• Best for: New construction, supplemental layers, attic knee walls
• Rebate eligible: Yes, when installed to minimum R-value by a registered contractor

Fibreglass batts are the most affordable insulation product but require precise installation to perform as rated. Gaps, compression, or improper fitting can reduce their effective R-value significantly. Batts are common in new construction but are less ideal for attic top-ups in existing homes, where blown-in products typically provide better coverage over irregular surfaces and around obstructions.

Below is a side-by-side text summary of the five main attic insulation types for a 1,000 sq ft Ontario attic:

Blown-In Fibreglass

Installed cost range: $1,500 – $2,500 | R-value range: R-38 to R-60 | Air sealing: Moderate | Rebate eligible: Yes | Best value rating: Excellent

Blown-In Cellulose

Installed cost range: $1,750 – $2,750 | R-value range: R-38 to R-60 | Air sealing: Moderate | Rebate eligible: Yes | Best value rating: Excellent (eco-conscious choice)

Open-Cell Spray Foam

Installed cost range: $5,250 – $7,000 | R-value per inch: R-3.5 to R-4 | Air sealing: Superior | Rebate eligible: Varies | Best value rating: Good for air sealing priority

Closed-Cell Spray Foam

Installed cost range: $6,000 – $10,000 | R-value per inch: R-6 to R-7 | Air sealing: Superior | Rebate eligible: Varies | Best value rating: Best for tight spaces or moisture control

Fibreglass Batts

Installed cost range: $750 – $1,500 | R-value range: R-11 to R-38 | Air sealing: Low | Rebate eligible: Yes | Best value rating: Good for new construction or supplements

The single biggest factor that can change the economics of an attic insulation upgrade is the availability of Ontario government rebates. Through the Home Renovation Savings Program — delivered by Enbridge Gas and Save on Energy — eligible homeowners can receive rebates of up to $5,000 toward qualifying attic insulation upgrades.

When you factor these rebates into the numbers, the real out-of-pocket cost for a full blown-in attic insulation upgrade on a typical Ontario home can drop to as low as $0 – $1,000 after rebate — an extraordinary value for an upgrade that will deliver energy savings for 20 to 30 years.

How Ontario Attic Insulation Rebates Work

• Your home must be your primary residence in Ontario
• Installation must be completed by a registered contractor (Constant Home Comfort qualifies)
• Insulation must achieve minimum R-value thresholds as set by the program (typically R-50 or higher for attics)
• A pre- and post-installation assessment may be required by some programs
• Rebates are paid directly to the homeowner after installation is verified

Constant Home Comfort handles the entire rebate process on your behalf — from confirming eligibility before we begin to submitting all required documentation after installation. You get the upgrade and the rebate with zero administrative hassle.

Rebate Stacking — Maximizing Your Return

In some cases, Ontario homeowners can stack municipal, provincial, and federal rebate programs to maximize their total return. For example, combining the Ontario Home Renovation Savings Program with Canada Greener Homes Initiative funding (where available) can significantly increase total rebate value. Our team stays current on all active programs and will help you identify every dollar you are entitled to claim.

When you receive a quote from Constant Home Comfort, it will clearly break down the cost components. Here is what typically makes up an attic insulation quote in Ontario:

Materials

The cost of the insulation product itself — whether blown-in bags, spray foam components, or batt rolls. Materials typically represent 40% to 60% of the total project cost, depending on product type.

Labour

The cost of skilled installation. Blown-in insulation is faster to install than spray foam, which requires careful preparation and curing time. Labour is where the difference between a quality contractor and a budget operator often shows — proper installation technique directly determines how close to rated R-value your insulation actually performs.

Air Sealing

Many contractors quote insulation and air sealing separately. At Constant Home Comfort, we include a standard air sealing assessment with every attic job, and clearly itemize any additional air sealing work required. Do not skip this step — air sealing can account for up to 40% of a home's total heat loss and is a prerequisite for most rebate programs.

Old Insulation Removal (If Applicable)

If your existing insulation must come out first, expect to add $1.00 – $2.00 per square foot for removal and disposal. This is standard and unavoidable when dealing with contaminated or asbestos-containing materials. We will always flag this during your free assessment so there are no surprises.

Attic Hatch and Bypass Sealing

Attic hatches are a notorious source of heat loss — most are uninsulated or minimally insulated. Sealing and insulating your attic hatch typically adds $150 – $400 to a project and pays for itself quickly in energy savings.

It is tempting to compare the cost of bags of blown-in insulation at a home improvement store to a professional quote and conclude you can save money doing it yourself. Here is why that calculation usually does not hold up:

• Rental equipment for blown-in insulation is available at some retailers, but correct machine calibration and blowing technique are required to achieve rated R-values — improper technique leaves you with significantly less coverage than you paid for
• Spray foam insulation requires professional equipment and certification and is not a realistic DIY option
• DIY installation does not qualify for Ontario government rebates, which can be worth up to $5,000 — a savings that typically far exceeds the labour portion of a professional quote
• Professional installers identify air bypasses, moisture issues, and ventilation problems that an untrained homeowner would miss — problems that cause ongoing damage and energy loss if left unaddressed
• Professional work is warranted and can be documented for home insurance and resale purposes

For the vast majority of Ontario homeowners, professional attic insulation installation — particularly when rebate eligibility is factored in — delivers significantly better value than DIY.

Attic insulation has one of the best returns on investment of any home improvement in Ontario. Here is a realistic payback scenario for a typical Ontario home:

• Home size: 1,500 sq ft two-storey detached
• Existing insulation: R-12 (poorly performing, common in pre-1990 homes)
• Upgrade to: R-60 blown-in fibreglass
• Total installed cost: approximately $3,000 – $4,000
• Less Ontario rebate: up to $5,000 (project may be fully covered or nearly so)
• Estimated annual energy savings: $400 – $700 per year depending on heating fuel type and usage
• Payback period (without rebate): approximately 5 – 8 years
• Payback period (with rebate): immediate savings from day one

Once your insulation upgrade is paid off — whether through rebates immediately or energy savings over a few years — every dollar of savings goes straight back into your pocket for the 20 to 30-year lifespan of the insulation. Few home upgrades deliver this kind of long-term financial return.

How much does attic insulation cost in Toronto?

For a typical Toronto detached home with a 1,000 – 1,400 sq ft attic, blown-in insulation generally runs between $1,500 and $3,500 installed before rebates. After Ontario rebates, many Toronto homeowners see their net cost drop to under $1,000 — and some projects are fully covered.

Is blown-in or spray foam insulation better value?

For most Ontario attics, blown-in insulation provides the best cost-per-R-value of any product. Spray foam is worth the premium when air sealing is the primary concern — for example, in older homes with significant bypass leakage, or in finished attic spaces where depth is limited. Our team will recommend the best combination for your specific home.

Does the cost include the rebate application?

When you work with Constant Home Comfort, yes — we manage the rebate application as part of our service at no additional charge. We submit all required documentation and coordinate with the rebate program on your behalf.

How do I get an accurate quote for my attic insulation?

The most accurate way is a free in-home assessment. We measure your attic, assess current insulation levels, identify air sealing needs, and give you a transparent written quote covering all cost components. There is no obligation and no pressure. Call us at 1 (888) 675-5907 or book online to get started.

Can I get financing for attic insulation?

Yes. Constant Home Comfort offers flexible financing options, including 0% interest plans, making it easy to upgrade your attic insulation with no large upfront payment. Combined with rebate savings, financing makes a full insulation upgrade accessible for virtually any Ontario homeowner.

Pricing transparency is a core part of how Constant Home Comfort operates. We do not believe in vague estimates or surprise charges — every homeowner deserves to know exactly what they are getting and what it will cost before any work begins.

Our free in-home attic insulation assessments are available across Toronto, the GTA, Ottawa, Hamilton, Barrie, and throughout Ontario. We will measure your attic, recommend the right insulation type and depth, walk you through all applicable rebates, and provide a clear, itemized written quote.

Call us today at 1 (888) 675-5907 or book your free assessment online. Let us show you exactly what attic insulation costs for your home — and how much you can save.

Constant Home Comfort. Transparent pricing. Professional installation. Maximum rebates.