Insulation FAQ — Renfrew County Homeowner Questions

Renfrew County falls in Climate Zone 6 under the Ontario Building Code. For new construction in Zone 6, OBC Supplementary Standard SB-12 requires a minimum of RSI 8.67 (approximately R-49) for attic insulation.

For existing homes being retrofitted, the code minimum isn't always the performance target. Most energy advisors recommend R-50 to R-60 in attics for Renfrew County homes — the extra insulation pays back quickly given the cold Ottawa Valley winters and the relatively low cost of blown-in cellulose or fibreglass compared to the energy it saves over time.

Common signs of inadequate insulation in Renfrew County homes:

• High heating bills, especially compared to neighbours with similar-sized homes
• Cold floors above a crawlspace, unheated garage, or basement
• Ice dams forming at the eaves in winter (heat escaping the attic melts snow unevenly)
• Drafts near exterior walls, window frames, or the junction of walls and ceilings
• Rooms that are consistently difficult to heat or cool to a comfortable temperature
• Frost or condensation forming on interior wall surfaces in cold weather

If you're seeing multiple signs, an EnerGuide audit by a registered energy advisor will give you a precise measurement of your current insulation levels and a prioritized list of upgrades.

Generally, no. Adding or upgrading insulation on its own does not require a building permit in Ontario. Permits are typically triggered when insulation work is part of a larger project that disturbs structural elements or significant portions of the building envelope.

Common insulation-only work that does not typically require a permit:

• Topping up attic blown-in insulation through existing access
• Adding batt insulation to an existing attic without structural changes
• Spray foaming a basement wall from the interior without altering the structure

If your insulation upgrade is part of a renovation affecting walls, structure, or mechanical systems, check with your local building department. See our guide to Renfrew County building permits for municipality-specific information.

DIY insulation is feasible for:

• Fibreglass batt — cutting and fitting batts between joists or studs is a manageable DIY task with proper safety equipment (gloves, eye protection, respirator).
• Blown-in cellulose or fibreglass — building supply retailers typically loan or rent blower machines when you purchase the material. Attic blow-in is commonly done as a two-person DIY job.

Spray foam is a different situation. Professional two-component closed-cell spray foam systems require trained applicators, specialized equipment, and proper ventilation during installation. Consumer-grade two-part kits from hardware stores are not equivalent — they produce significantly less yield, lower R-values, and may not qualify for EnerGuide grant programs. DIY spray foam also has health and fire risks if applied incorrectly.

Yes — insulation is one of the primary eligible upgrades under the Canada Greener Homes Loan. The program provides up to $40,000 at 0% interest for qualifying home energy retrofits.

To access the loan for insulation:

1. Book a pre-renovation EnerGuide audit by an NRCan-registered energy advisor
2. Have the recommended insulation upgrades completed by a qualified contractor
3. Complete a post-renovation audit confirming the improvement
4. Submit the audit reports and invoices to the program

See our full guide to the Canada Greener Homes Loan for current program details, eligibility, and how to apply.

Insulation lifespan varies significantly by material type:

• Fibreglass batt: 20–30 years before settling and performance degradation. Susceptible to moisture damage and air gaps if not properly installed.
• Cellulose blown-in: 20–30 years. Can settle 15–20% in the first few years after installation, which reduces effective R-value. Quality installers account for this by installing slightly above the target depth.
• Closed-cell spray foam: 80+ years. Rigid, does not settle, does not absorb moisture. The most durable insulation option available.
• Open-cell spray foam: Similar longevity to closed-cell in terms of material durability, but requires a separate vapour barrier and is less moisture-resistant.

Closed-cell spray foam is generally the top-performing choice for Renfrew County basements, for three reasons specific to the local climate and construction context:

• Moisture resistance: Foundation walls in the Ottawa Valley experience significant moisture migration, especially in spring and after heavy rain. Closed-cell foam does not absorb water.
• Highest R-value per inch: At approximately R-6 to R-7 per inch, it achieves code-minimum performance in a thinner profile — critical when basement space is limited.
• Built-in vapour barrier: Closed-cell foam at sufficient thickness (typically 2 inches or more) meets the vapour barrier requirement, eliminating a separate installation step.

Alternatives include rigid foam board (EPS or XPS) attached to the foundation wall, or fibreglass batt between stud framing — both require careful vapour barrier management and are more vulnerable to moisture if the foundation ever leaks.

Yes — adequate attic insulation is the primary prevention method for ice dams, which are a common problem in Renfrew County given the significant snowfall and cold temperatures.

Ice dams form through this sequence: heat from the living space escapes through an under-insulated attic → warms the underside of the roof → melts snow on the upper section of the roof → meltwater flows down to the cold eave overhang (which is outside the building envelope) → refreezes into ice. The ice buildup creates a dam that forces water back up under shingles, where it can penetrate the roof deck and cause interior water damage.

Proper attic insulation keeps the roof surface closer to the outside air temperature — consistent and cold — preventing the melt-refreeze cycle. Adequate attic ventilation works in combination with insulation to further equalize roof surface temperatures.

Ice and water shield installed at the eaves provides a second line of defence, but it treats the symptom. Insulation addresses the root cause. See our insulation cost guide for pricing on attic upgrades.