Attic Insulation Toronto

Professional Attic Insulation in the GTA

Last updated: March 6, 2026

Konstruction Group provides professional attic insulation services for new custom homes, multiplexes, and existing home upgrades throughout Toronto. We primarily use blown-in insulation for attics - it provides complete coverage and achieves the R60 rating required by Ontario Building Code. Whether you're building new or upgrading an older home's attic, our insulation work coordinates with framing and drywall to deliver quality results that reduce energy costs and improve comfort.

Attic Insulation Methods

• Blown-In Fiberglass – Loose-fill fiberglass blown to R60 depth - our primary method for attic insulation
• Blown-In Cellulose – Recycled fiber material - eco-friendly option with similar performance
• Spray Foam (Cathedral Ceilings) – For exposed ceilings and cathedral roofs where blown-in isn't suitable

Why Blown-In for Attics

Blown-in insulation is ideal for attics because it covers the entire floor surface completely, filling around joists, wiring, pipes, and other obstacles. Unlike batt insulation that must be cut and fitted around obstructions, blown-in material flows into every gap and achieves consistent R-value across the entire attic floor. This complete coverage is why blown-in is the standard for attic insulation in both new construction and retrofit projects. In the GTA's cold climate (Zone 6 under the National Energy Code), eliminating thermal gaps in attic insulation has a direct impact on heating costs and occupant comfort.

New Construction Attics

For new custom homes and multiplexes, we install attic insulation after all other attic work is complete - drywall, electrical, HVAC rough-in, and any attic mechanicals. We blow insulation to achieve verified R60 coverage with depth markers throughout the attic. Ventilation baffles at eaves maintain soffit airflow while preventing insulation from blocking ventilation.

Existing Home Upgrades

Many older Toronto homes have inadequate attic insulation - sometimes only R20 or R30, far below current requirements. We can add blown-in insulation on top of existing insulation to bring your attic up to current R60 standards. This is a non-invasive upgrade that doesn't require removing existing insulation or disturbing ceilings below, making it one of the most cost-effective energy improvements available. Before blowing, we check for moisture issues, ensure soffit vents are clear, and verify that recessed lights are IC-rated for insulation contact.

Attic Insulation Cost in Toronto

Attic insulation in Toronto runs $1.50 to $3.50 per square foot for blown-in to R-60, the OBC zone 6 minimum for new construction. Spray foam pushes the per-square-foot rate higher because of material cost and rig time. A typical 1,500 sq ft attic costs $2,500 to $4,800 in blown-in fibreglass or cellulose, and $7,000 to $11,000 in closed-cell spray foam at the same R-value. Pricing varies with attic accessibility, existing insulation removal, baffle and ventilation upgrades, and whether the job includes air sealing penetrations before blowing. We quote turnkey: insulation, vent baffles, attic hatch insulation, and final inspection. Quotes are typically returned within 24 hours of a site visit or accurate measurements.

R-Value Targets and Insulation Depth

Ontario Building Code SB-12 requires R-60 for attic insulation in Climate Zone 6 (most of southern Ontario, including the entire GTA). Different materials hit R-60 at different depths because their R-value per inch varies. Blown fibreglass at R-2.5 per inch needs roughly 24 inches of loose-fill to hit R-60. Blown cellulose at R-3.5 per inch hits R-60 in about 17 inches. Open-cell spray foam at R-3.7 per inch needs about 16 inches of foam thickness. Closed-cell spray foam at R-6.5 per inch hits R-60 in about 9 inches, which is why it is the only practical option for cathedral ceilings and shallow roof cavities.

Top-Up vs Full Replacement

Most existing Toronto attic upgrades are top-ups, not full replacements. If your current insulation is dry and uncontaminated, we blow new fibreglass or cellulose directly on top to bring total coverage from R-12 or R-22 (common in homes built before 1985) up to the current R-60 target. A typical top-up runs $1,200 to $2,800 depending on attic size and how much new insulation is needed. Full replacement is required when existing insulation is wet, mouldy, contaminated by rodent activity, or contains vermiculite (older Zonolite-brand vermiculite from before 1990 may contain asbestos and requires hazmat-certified removal). Full removal plus new R-60 install runs $4,500 to $9,500 for a typical attic. We test for vermiculite before any removal, and our crews are PPE-equipped and trained on the disposal protocol if asbestos is present.

Enbridge and Home Renovation Savings Program Rebates

Ontario homeowners can recover a meaningful portion of attic insulation cost through the Home Renovation Savings Program, co-funded by Enbridge Gas and saveONenergy and managed by IESO. Attic top-ups qualify for up to $250 in rebates and full attic insulation upgrades qualify for up to $1,500. Rebate eligibility requires a pre-upgrade home energy assessment by a registered Energy Advisor (the assessment itself is rebate-eligible, typically $200 to $400 net). The combined cap across all eligible upgrades is $10,000 per home. Enbridge gas customers in the GTA are eligible whether they currently use gas heat or not. We do not handle the rebate application paperwork, but we provide the install documentation, R-value verification, and product receipts the Energy Advisor and program portal need at post-install verification.

What We Provide vs. What You Need

• We Provide – Blown-in insulation, ventilation baffles, depth verification, and cleanup
• You Provide – Attic access, all other work complete (new construction), no storage in attic

Why Choose Konstruction Group

• R60 Verified – Depth markers confirm complete coverage
• Proper Ventilation – Baffles installed to maintain soffit airflow
• $10M Liability Insurance – Full coverage for attic insulation work in new builds and existing homes
• WSIB Compliant – Workers insured for attic access and overhead insulation installation
• New & Existing – We serve both new construction and upgrade markets
• 1-Year Warranty – Attic insulation R-value and coverage guaranteed for one year