Blown-In Insulation for Attics: Ottawa Homeowners’ Guide

The Most Important 1,000 Square Feet in Your Home

In a typical Ottawa home, the attic often spans 1,000 square feet or more—making it the single most critical area for energy performance. Heat rises relentlessly in winter, turning an under-insulated attic into your home’s biggest energy leak. In summer, a hot attic radiates heat downward, forcing your air conditioner to work overtime.

For any Ottawa home built before 2010, attic insulation is usually far below modern standards. Upgrading with blown-in insulation is the most effective, affordable retrofit available, delivering seamless coverage that traditional batts simply can’t match.

At Bison Insulation, we specialize in professional attic insulation in Ottawa, with blown-in methods providing superior results for the vast majority of local properties.

Why the Attic Should Be Your Top Insulation Priority

Ottawa falls in Climate Zone 6-7, where building codes recommend a minimum R-60 for attics. Yet many older homes in neighborhoods like Glebe, Westboro, Centretown, or Kanata have only R-20 to R-40—often settled or uneven.

Prioritizing the attic delivers the highest return on investment:

• Reduces overall heat loss by 25-40%
• Cuts heating and cooling bills by 20-40%
• Eliminates cold spots and drafts
• Prevents costly ice dams and roof damage
• Improves indoor comfort year-round

Blown-in insulation shines in attics because it flows into every irregular space, surrounding joists, wires, and obstacles without gaps.

Learn more about our comprehensive blown-in insulation services in Ottawa.

Proper Ventilation: The Key to a Healthy, Long-Lasting Attic

The Danger of Blocking Soffit Vents

One of the most common insulation mistakes is overfilling to the roof edges, burying soffit vents. This traps moisture from roof leaks, bathroom exhaust, or humidity, leading to condensation, wood rot, mold growth, and premature shingle failure.

In Ottawa’s humid summers and wet winters, proper airflow is non-negotiable.

How Soffit Baffles Protect Your Roof

Professional installers always install durable soffit baffles (vent chutes) before blowing insulation. These create clear channels from eaves to ridge, ensuring continuous ventilation while allowing full insulation depth right to the edges.

This balanced approach keeps the roof deck dry, prevents ice dams, and maintains shingle warranties.

Cellulose vs Fiberglass Blown-In: Which Material is Right for Your Attic?

Blown-In Cellulose Insulation

• Made from 85%+ recycled paper, treated with non-toxic borates
• Dense structure provides excellent air sealing and convection control
• Superior soundproofing—ideal for homes near busy roads like the 417
• Naturally regulates moisture without losing performance
• R-value: approximately 3.8 per inch
• Added pest and mold resistance
• Eco-friendly choice for sustainability-focused homeowners

Cellulose often performs best in older Ottawa homes with drafts and variable humidity.

Blown-In Fiberglass Insulation

• Composed of spun glass fibers
• Naturally non-combustible—no chemical treatments needed
• Minimal long-term settling for consistent R-value
• Lightweight, allowing deeper fills in restricted spaces
• R-value: 3.2-4.0 per inch
• Excellent for fire safety priorities

Both materials achieve R-60 easily and safely, but the choice depends on your home’s specific needs. Our experts evaluate during assessment to recommend the optimal option.

The Cost-Saving “Top-Up” Approach

When You Can Build on Existing Insulation

In many cases, old insulation is still functional—just insufficient. If it’s dry, even, and free of mold or pests, we can “top up” directly over it.

This method:

• Saves thousands compared to full removal
• Reduces mess and disruption
• Achieves modern R-60 quickly (often in one day)

We precisely measure current depth and calculate the exact addition needed for uniform coverage.

When Full Removal is Required

Damaged, heavily settled, water-stained, or contaminated insulation must be removed first for health and performance reasons.

Our safe, dust-controlled insulation removal in Ottawa uses HEPA-filtered equipment. If mold is present, we provide professional mold removal in Ottawa to ensure a clean, healthy start before installing fresh blown-in material.

Preventing Ice Dams: Essential Protection for Ottawa Roofs

Ice dams form when heat escaping into the attic melts snow unevenly, causing refreezing at the colder eaves. The resulting ice ridges damage shingles, gutters, and interiors—often costing thousands to repair.

High R-value blown-in insulation keeps the entire attic cold and uniform, eliminating the temperature differences that trigger melting. Combined with proper baffles and air sealing, it virtually eradicates ice dam risk.

Air Sealing: Maximizing Your Attic’s Performance

Insulation works best when paired with air sealing. Before blowing material, we seal:

• Top plates where walls meet ceiling
• Recessed lighting and electrical boxes
• Plumbing and wire penetrations
• Attic hatch with weatherstripping

This stops the stack effect—warm air rising and escaping—while preventing cold drafts from entering living spaces.

For challenging areas like cathedral ceilings or rim joists, we often complement blown-in with targeted spray foam insulation in Ottawa.

Extending Efficiency Beyond the Attic

A well-insulated attic often highlights heat loss elsewhere. Many homeowners add:

• Insulation for floors over unheated spaces like garages—see our floor insulation in Ottawa
• Wall retrofits with dense-pack blown-in

Creating a complete thermal envelope maximizes savings and comfort.

Professional Installation: The Difference That Matters

Attics present hazards—narrow joists, old wiring, and extreme temperatures. Professional teams ensure:

• Precise depth and density calculations
• Maintained ventilation pathways
• Thorough air sealing
• Uniform coverage without voids
• Compliance for rebates like Canada Greener Homes Grant
• Full cleanup and workmanship warranty

Most attic blown-in projects are completed in a single day with minimal household disruption.

What Ottawa Homeowners Gain from Attic Upgrades

Thousands of local families have experienced:

• Significantly lower energy bills (often $500-1,500 annually)
• Even temperatures throughout the house
• No more ice dams or roof leaks
• Quieter interiors from enhanced soundproofing
• Increased home value and resale appeal

These results are consistent when installation follows best practices.

Planning Your Attic Insulation Project

1. Schedule a free, no-obligation assessment
2. Receive detailed recommendations and quote
3. Review material options and rebate eligibility
4. Book convenient installation timing
5. Enjoy immediate benefits next season

Conclusion: Start at the Top for Maximum Impact

Blown-in attic insulation is the single most effective upgrade for Ottawa homeowners facing extreme weather. From dramatic energy savings and ice dam prevention to improved comfort and home protection, the benefits are immediate and long-lasting.

Don’t let another winter’s heat escape through your roof. Professional installation ensures you get full performance from your investment.

Contact Bison Insulation today for your free attic evaluation. Visit our homepage to explore all services and take the first step toward a more efficient home.

Your attic upgrade will pay dividends for decades—make it happen this year.