Updated August 2026, pricing is shown in Canadian dollars and is intended for budgeting, not as a fixed quote.
Quick answer: how much does blown-in insulation cost per square foot in Canada?
For a straightforward attic top-up, a practical 2026 planning range for blown-in insulation cost per square foot in Canada is about $1.50 to $3.50 installed. At that rate, a 1,000 sq. ft. attic may cost approximately $1,500 to $3,500, while a 1,200 sq. ft. attic may cost about $1,800 to $4,200.
The final quote depends on the existing and target R-value, material, attic access, air sealing, ventilation baffles, and whether wet, contaminated, or vermiculite insulation must be addressed first. Tax, hazardous material testing, remediation, and extensive removal may sit outside the basic per-square-foot price.
| 2026 planning figure | Typical range | What it means |
|---|---|---|
| Installed cost per sq. ft. | $1.50 to $3.50 | Common budgeting range for a straightforward attic top-up |
| 1,000 sq. ft. attic | $1,500 to $3,500 | Before major removal, remediation, or access work |
| 1,200 sq. ft. attic | $1,800 to $4,200 | Final cost changes with current depth and target R-value |
| Typical on-site work | Often one day | Complex preparation or removal can extend the project |
Public Canadian cost guides do not all use the same scope. For example, HomeStars currently lists typical professional installation at about $1.50 to $2.45 per square foot, while projects targeting a higher R-value or including more preparation can cost more. That is why the starting R-value and included work matter more than a single advertised rate.
Blown-in attic insulation cost by attic size
The table below applies the $1.50 to $3.50 planning range to the attic floor area. It is useful for an early budget, but it does not include taxes or major corrective work.
| Attic floor area | Estimated installed range |
|---|---|
| 500 sq. ft. | $750 to $1,750 |
| 800 sq. ft. | $1,200 to $2,800 |
| 1,000 sq. ft. | $1,500 to $3,500 |
| 1,200 sq. ft. | $1,800 to $4,200 |
| 1,500 sq. ft. | $2,250 to $5,250 |
| 2,000 sq. ft. | $3,000 to $7,000 |
A two-storey 2,000 sq. ft. home does not necessarily have a 2,000 sq. ft. attic. Measure the ceiling area directly below the attic, then exclude areas that are not part of the work. A contractor should confirm the measurement during the inspection.
What changes the cost of blown-in insulation?
1. Your current R-value and target R-value
A shallow top-up requires fewer bags and less labour than taking a poorly insulated attic to a much higher target. The installer should measure existing insulation at several locations, identify the material, and calculate how much additional insulation is required. A quote that lists only square footage, without current depth or target R-value, is incomplete.
2. Cellulose or fibreglass
Cellulose generally provides more R-value per inch, while loose-fill fibreglass usually requires greater depth to reach the same target. Product coverage, installed density, local availability, and the number of bags all affect cost. Compare the installed assembly and documented R-value, not only the price per bag.
3. Air sealing before the insulation is added
Loose-fill insulation slows heat flow, but it is not a complete air barrier. Plumbing stacks, wiring penetrations, attic hatches, partition top plates, and some light fixtures can allow warm, moist indoor air into the attic. These leakage points should be assessed and sealed where appropriate before they disappear under new insulation.
4. Soffit baffles and attic ventilation
Insulation should not block intake air at the eaves. Baffles may be needed to keep a clear path from the soffits into the attic. Adding more insulation without checking airflow can hide the original problem and contribute to condensation. Read our guide to proper attic ventilation for the roof-side details.
5. Removal, moisture, pests, and contamination
Dry, clean existing insulation can often remain in place, but wet, mouldy, pest-contaminated, or fire-damaged material needs a different plan. Removal, disposal, leak repair, electrical correction, or mould remediation can add significantly to the total. New insulation should not be used to cover an unresolved roof leak or attic moisture problem.
6. Access and attic layout
A small hatch, low roof pitch, multiple attic sections, cathedral ceiling transitions, or limited safe working space can increase labour. Larger open attic floors are usually easier to cover consistently than tight areas around complex roof framing.
Cellulose vs fibreglass blown-in insulation
Both materials can work well when the attic is dry, prepared correctly, and installed to the product coverage chart. Natural Resources Canada lists cellulose, glass fibre, and mineral fibre among common loose-fill materials and notes that loose fill is especially suitable for attics and enclosed spaces. Its published material guide shows that loose-fill products commonly fall within roughly R-2.2 to R-3.8 per inch, depending on the product.
| Comparison | Cellulose | Fibreglass |
|---|---|---|
| Typical composition | Recycled paper fibre treated for fire resistance | Loose glass fibre |
| Typical R-value per inch | About R-3.2 to R-3.8 | About R-2.2 to R-3.0 |
| Depth required | Usually less depth for the same nominal R-value | Usually more depth for the same nominal R-value |
| Common advantage | Good coverage and higher R-value per inch | Lightweight and widely available |
| Important consideration | Installed density and settled thickness must follow the product chart | Coverage must remain even, especially near eaves and obstructions |
Do not choose the material from a generic R-value alone. Check the Canadian product label, coverage chart, required number of bags, settled thickness where applicable, fire safety requirements, and warranty. You can review the federal Natural Resources Canada insulation material guide for a broader comparison.
How much R-value does a Canadian attic need?
There is no single retrofit R-value that applies to every existing home in Canada. The appropriate target depends on the local climate zone, the roof and ceiling assembly, existing insulation, applicable building requirements, and any rebate criteria.
Natural Resources Canada’s general retrofit guidance lists recommended nominal roof or ceiling levels of R-55 in Climate Zone 5, R-60 in Climate Zone 6, and R-80 in colder zones. These are national guidance values, not a statement that every existing attic is legally required to reach the same number. Confirm the target for your home with the local building authority, an energy advisor, or a qualified contractor.
The federal Keeping the Heat In guide for roofs and attics also recommends dealing with air leakage, moisture, heat-producing fixtures, and ventilation before adding insulation. That sequence matters as much as the final depth.
Can blown-in insulation be added over existing insulation?
Yes, in many attics new loose-fill insulation can be added over existing material if the old insulation is dry, clean, and in stable condition. Before topping up, the attic should be checked for:
- Active or previous roof leaks
- Condensation, frost, staining, or mould
- Pest activity or contaminated material
- Unsafe electrical conditions
- Unprotected heat-producing fixtures and chimney clearances
- Blocked soffit vents or missing baffles
- Air leakage around the attic hatch and ceiling penetrations
If staining is present, first determine whether it came from exterior water entry or indoor moisture. Our comparison of a roof leak versus attic condensation explains why the repair is different.
Important safety note about vermiculite
Some older vermiculite insulation may contain asbestos. Health Canada advises homeowners not to disturb suspected vermiculite and to use qualified professionals for testing and removal when renovation is planned. Do not rake it aside, vacuum it, or blow new material over it before it has been properly assessed. See Health Canada’s asbestos guidance.
Is blown-in insulation worth it?
It can be a strong upgrade when an accessible attic has low or uneven insulation, but the result depends on the starting condition. Canadian energy data shows that space and water heating account for 79 percent of residential energy consumption, so improving the building envelope can matter. Still, no responsible contractor can promise one universal percentage reduction in your bill.
Your savings will vary with the existing R-value, air leakage, home size, heating system, thermostat settings, energy prices, climate, and occupant behaviour. The upgrade is most likely to provide noticeable comfort and energy benefits when it corrects a genuinely under-insulated and air-leaky attic.
Insulation also needs to work with the roof system. Air sealing limits warm, moist air entering the attic, insulation slows heat transfer, and ventilation helps manage moisture that reaches the space. Our guide to whether a new roof improves insulation and energy performance explains where roofing work fits into that system.
Ontario attic insulation rebates in 2026
As of August 2026, Ontario’s Home Renovation Savings program advertises a standalone attic insulation rebate of up to $1,250 for eligible homes. The January 2026 program requirements state that the rebate is calculated at 50 percent of eligible attic insulation cost after tax, up to the applicable maximum. They also require pre-registration, an in-home visit, and installation by a participating insulation contractor.
Eligibility and deadlines can change. Check the current Home Renovation Savings program before hiring a contractor or beginning work. Do not assume a project qualifies until the program confirms it, and do not start an eligible upgrade before completing any required registration or inspection.
DIY vs professional blown-in insulation
Blower rentals can make a DIY top-up look simple, but placing the material is only one part of the job. The preparation requires safe attic access, suitable protective equipment, air sealing, baffle installation, fixture and chimney clearances, a reliable bag count, depth markers, and even coverage. The person in the attic also needs a second person feeding the machine.
A DIY approach may be reasonable for an experienced homeowner with a dry, uncomplicated attic and no suspected hazardous material. Professional assessment is the safer choice when there is vermiculite, mould, pest contamination, wiring concerns, a history of leaks, limited access, or uncertainty about ventilation and code requirements.
What should a blown-in insulation quote include?
- Measured attic floor area
- Existing insulation type, condition, depth, and estimated R-value
- Target R-value and the product being installed
- Required installed depth, settled depth where applicable, and estimated bag count
- Air sealing locations included in the scope
- Number and location of ventilation baffles
- Protection around fixtures, flues, chimneys, and the attic hatch
- Removal, disposal, testing, or remediation listed separately
- Photos or measurements confirming final depth and coverage
- Labour and material warranty, taxes, exclusions, and payment terms
If two quotes are far apart, compare these line items before assuming one contractor is simply cheaper. One quote may cover insulation only, while another includes the preparation needed for the insulation to perform properly.
How RonOvations approaches attic insulation
RonOvations works on both roofing and blown-in attic insulation, so the assessment does not stop at the insulation depth. The team checks the condition of the attic, signs of water entry or condensation, airflow at the eaves, and the relationship between the ceiling, insulation, ventilation, and roof above it.
A typical scope can include an attic inspection and R-value assessment, preparation and air sealing where required, removal of damaged material when included in the quote, professional loose-fill application, and a final thickness and coverage check. If the attic shows signs of a roof problem, the cause should be dealt with before clean insulation is installed.
Homeowners planning roof work can also review what roofers check during a professional roof inspection. Looking at the roof and attic together helps avoid paying for an insulation top-up that covers evidence of an unresolved leak or ventilation issue.
Frequently asked questions
How much does blown-in insulation cost per square foot in Canada?
A practical 2026 planning range is about $1.50 to $3.50 per square foot installed for a straightforward attic top-up. Projects involving removal, hazardous material testing, mould remediation, extensive air sealing, or difficult access can cost more.
How much does blown-in insulation cost for a 1,200 sq. ft. attic?
Using the basic planning range, a 1,200 sq. ft. attic may cost approximately $1,800 to $4,200 installed. The quote should confirm the attic area, existing R-value, target R-value, material, preparation, and exclusions.
Is cellulose or fibreglass blown-in insulation cheaper?
Cellulose material is often competitively priced and usually provides more R-value per inch, but local product cost and the required installed density can change the total. Compare written quotes for the same attic area and target R-value rather than comparing bag prices.
How thick should blown-in insulation be?
The required depth depends on the product’s R-value per inch, installed density, existing insulation, and target R-value. Use the manufacturer’s Canadian coverage chart. A generic depth such as 12 or 16 inches cannot apply to every product or attic.
Does blown-in insulation need an air barrier?
Yes, loose-fill insulation is not a substitute for a continuous air control layer. Accessible ceiling penetrations should be assessed and sealed where appropriate before new material is added. Air sealing also helps reduce the movement of warm, moist indoor air into a cold attic.
Can blown-in insulation prevent ice dams?
It can reduce heat transfer to the roof deck, but insulation alone is not a complete ice dam solution. Air leaks, uneven coverage, ventilation, roof geometry, and outdoor conditions also matter. The attic should be evaluated as a complete system.
How long does blown-in insulation last?
There is no universal replacement date. Dry and undisturbed fibreglass or cellulose can remain useful for decades, but moisture, pests, physical disturbance, and settling can reduce performance. Inspect the attic after a roof leak, major roof work, or a noticeable change in comfort or energy use.
Is there an Ontario rebate for attic insulation in 2026?
As of August 2026, eligible Ontario homeowners may qualify for up to $1,250 through the Home Renovation Savings standalone attic insulation stream. Registration, contractor, property, existing insulation, target R-value, and deadline requirements apply, so verify eligibility on the official program website before work begins.
Sources and editorial note
This guide was updated in August 2026 using current public Canadian pricing benchmarks, Natural Resources Canada retrofit guidance, Health Canada safety information, and current Ontario Home Renovation Savings program requirements. Pricing is an editorial planning range and does not represent a guaranteed RonOvations quote. Technical review should be completed by the RonOvations roofing and insulation team before publication.
