Blown-In Attic Insulation

Blown-in attic insulation is one of the highest-return upgrades available to Canadian homeowners — reducing heating costs, preventing ice damming, and extending roof lifespan. MKT Roofing & Exteriors installs professional blown-in insulation to Ontario Building Code and Natural Resources Canada standards.

Attic Insulation project completed by MKT Roofing & Exteriors

Attic insulation — Ontario climate data

Heating accounts for about 63% of energy use in a typical Canadian home — and a poorly insulated attic can account for up to 25% of total heat loss.

Natural Resources Canada, Energy Efficiency Trends in Canada, 2024

NRC recommends R-50 to R-60 for attic insulation in Ontario’s Climate Zones 6 and 7 — the zones covering Barrie, Muskoka, Huntsville and Northern Ontario.

NRC EnerGuide, Climate Zone Map for Insulation

The average Ontario home built before 1990 has only R-12 to R-20 of attic insulation — a significant energy loss and ice-dam risk that blown-in upgrades correct.

CMHC, Housing in Canada Online

Insulation types compared

Type	R-value / inch	Installation	Best application
Blown-in cellulose	R-3.5	Machine (half day)	Retrofit attics, irregular spaces
Blown-in fibreglass	R-2.5	Machine (half day)	Sensitive occupants, moisture risk
Batt fibreglass	R-2.9–3.8	Manual (full day)	New construction with clear joists
Rigid foam board	R-5–6.5	Manual (full day)	Roof deck or basement walls
Spray foam (2-part)	R-6+	Professional only	Air sealing priority, rim joists

For most Ontario retrofit attics, blown-in cellulose or fibreglass is the recommended approach — superior coverage, faster installation and comparable or lower cost vs. batts.

Why upgrading your attic insulation matters

Energy savings

Upgrading from R-20 to R-60 in a typical Ontario home can cut annual heating costs by $400 to $1,000. At Northern Ontario gas and propane prices, most projects pay for themselves in 3 to 5 years.

Ice-dam prevention

Properly insulated attics eliminate the temperature differential that melts snow and refreezes it at the eaves — the most effective, permanent solution to ice damming, more reliable than heating cables.

Longer roof life

Attic temperatures swing from -25°C to +60°C between seasons, degrading shingles from the inside. Stable attic temperatures reduce that thermal stress and preserve warranty validity.

The air-sealing-first principle

Adding insulation without first air-sealing penetrations — electrical boxes, plumbing stacks, duct transitions — significantly reduces effectiveness. Warm air bypassing insulation through gaps carries far more heat loss than conduction through the insulation itself. We air-seal before installing, so the thermal performance our quotes promise is the performance you get.

Our installation process

Full attic inspection and existing R-value documentation
Air sealing of all electrical, plumbing and duct penetrations
Baffle installation at eaves to protect soffit ventilation airflow
Machine installation of blown-in material to target R-value (R-50 minimum, R-60 recommended)
Depth verification and coverage-consistency check
Final inspection documentation and homeowner walkthrough

Cost & payback overview

Home size (attic sq ft)	Typical cost (to R-60)	Annual heating savings	Payback
Up to 800 sq ft	$1,500–$2,500	$300–$500 / yr	3–6 years
800–1,500 sq ft	$2,000–$3,500	$500–$800 / yr	3–5 years
1,500–2,500 sq ft	$3,000–$5,000	$700–$1,200 / yr	3–5 years
2,500+ sq ft	$4,500+	$1,000+ / yr	3–5 years

Savings estimates are based on average Ontario natural-gas pricing. Results vary by home condition, heating system and local rates.

Ready to protect your home?

Get a free, no-obligation written quote for your attic insulation project from our own licensed crew.

Request a quote

Frequently asked questions

What R-value should my attic have in Ontario?

NRC recommends R-50 to R-60 for Ontario Climate Zones 6 and 7. R-60 is the target for most Central and Northern Ontario locations including Barrie, Muskoka and Huntsville.

How much does blown-in attic insulation cost in Ontario?

Most residential projects range from $1,500 to $5,000 depending on attic size and existing insulation level. We provide free on-site assessments and written quotes.

How long does installation take?

Most residential jobs complete in half a day. Homes requiring extensive air sealing may take a full day.

Can I pair insulation with a roof replacement?

Yes — this is often the ideal timing and most cost-efficient approach, particularly when ice damming or poor ventilation has been a factor.

Get in touch

Get a free attic insulation quote

Tell us about your roof or exterior project and we’ll get back to you with a free, no-obligation written quote. No pressure, no subcontractors — just an honest assessment from our own crew.

(705) 279-1774
Call or text — same-day for emergencies sales@mktroofingandexteriors.ca202 Yeates Ave, Barrie, ON L4N 4C6
Also serving from Baseline Rd, Severn, ON P0E 1N0Follow us on Facebook