Below is a side-by-side comparison of the most commonly used basement insulation types in Ontario, based on current market pricing for material and labour. All figures are in Canadian dollars and reflect typical costs for a standard basement with approximately 1,000–1,500 sq ft of wall area before rebates are applied.

Closed-Cell Spray Foam  |  $4.00–$7.00 per sq ft  |  $6,000–$12,000+ total  |  R-6 to R-7 per inch

Open-Cell Spray Foam  |  $1.50–$3.00 per sq ft  |  $2,500–$5,500 total  |  R-3.5 per inch

Rigid Foam Board (XPS)  |  $1.00–$2.50 per sq ft  |  $1,800–$4,500 total  |  R-5 per inch

Rigid Foam Board (EPS)  |  $0.80–$2.00 per sq ft  |  $1,500–$3,800 total  |  R-3.6 to R-4.2 per inch

Fiberglass Batt  |  $0.50–$1.50 per sq ft  |  $900–$2,800 total  |  R-3 to R-4 per inch

Mineral Wool (Rockwool) Batt  |  $1.00–$2.00 per sq ft  |  $1,500–$3,500 total  |  R-3.7 to R-4.2 per inch

Note: These ranges reflect installed costs including labour. DIY installations will reduce the cost significantly for batt and rigid board options but are not recommended for spray foam, which requires certified equipment and protective gear.

When you receive a professional quote for basement insulation, the price should typically include:

• Pre-installation assessment and R-value recommendations
• Material supply and delivery
• Surface preparation (clearing, cleaning, minor crack filling)
• Rim joist insulation and air sealing
• Labour for installation
• Vapour barrier installation where required by Ontario building code
• Site cleanup and disposal of old insulation materials (if applicable)

Some contractors quote materials and labour separately — always confirm what is included before comparing prices between providers.

Closed-cell spray foam is consistently the most expensive option per square foot, and also the highest-performing. Here's why many Ontario homeowners choose to invest in it despite the higher upfront cost:

Closed-Cell Spray Foam

• Cost: $4.00–$7.00 per sq ft installed
• R-value: R-6 to R-7 per inch — highest available in a single layer
• Air and vapour barrier: Acts as both simultaneously — no separate vapour barrier required
• Moisture resistance: Excellent — will not absorb water or support mould growth
• Structural rigidity: Adds minor structural reinforcement to basement walls
• Best for: Unfinished basements, high-moisture environments, maximum energy savings, and rebate programs requiring high R-values

Open-Cell Spray Foam

• Cost: $1.50–$3.00 per sq ft installed
• R-value: R-3.5 per inch — requires more thickness to meet code minimums
• Air barrier: Yes — excellent air sealing properties
• Vapour barrier: No — a separate 6-mil poly vapour barrier is required
• Sound attenuation: Excellent — preferred for basement home theatres or music rooms
• Best for: Interior basement walls where moisture is controlled, noise reduction is a priority, and budget is a consideration over closed-cell

Rigid foam board is one of the most popular choices for Ontario basement insulation upgrades because it strikes a strong balance between performance, moisture resistance, and price.

XPS (Extruded Polystyrene — e.g., Styrofoam)

• Cost: $1.00–$2.50 per sq ft installed
• R-value: R-5 per inch
• Moisture resistance: Very good — low water absorption
• Vapour barrier: Acts as a partial vapour retarder at 2" thickness; full vapour barrier may still be needed
• Best for: Basement walls with slight moisture concerns, rim joists, and unfinished basement applications

EPS (Expanded Polystyrene)

• Cost: $0.80–$2.00 per sq ft installed
• R-value: R-3.6 to R-4.2 per inch
• Moisture resistance: Good — more permeable than XPS but still effective
• Environmental profile: No HFCs used in manufacturing — lower global warming potential than XPS
• Best for: Budget-conscious homeowners who still want a rigid foam solution with solid performance

Fiberglass and mineral wool batts remain the go-to choice for budget-driven projects — especially for finishing a basement where the walls will be covered with drywall.

Fiberglass Batt

• Cost: $0.50–$1.50 per sq ft installed
• R-value: R-3 to R-4 per inch (R-12 to R-20 depending on thickness)
• Air sealing: None — requires separate air sealing strategy
• Vapour barrier: Separate 6-mil poly vapour barrier required
• Key risk: Will absorb moisture if vapour management is inadequate — potential mould risk
• Best for: Dryer basements with good moisture control, budget-constrained projects, walls that will be fully finished

Mineral Wool (Rockwool) Batt

• Cost: $1.00–$2.00 per sq ft installed
• R-value: R-3.7 to R-4.2 per inch
• Fire resistance: Naturally fire-resistant — no additional treatment needed
• Moisture resistance: Will not absorb water and dries easily — outperforms fiberglass in damp conditions
• Sound performance: Excellent — dense structure provides effective soundproofing
• Best for: Homeowners who want batt insulation with better moisture and fire performance than fiberglass

The price ranges above are starting points. Your actual quote will be influenced by several project-specific variables:

• Basement size: The total wall area (perimeter x wall height) is the primary cost driver. A larger basement means more material and more labour hours.
• Wall condition: Cracks, efflorescence (white mineral deposits), or existing moisture damage must be addressed before insulation can be installed — this can add $500–$2,000+ to the project.
• Existing insulation removal: If old, damaged, or mould-contaminated insulation needs to be removed and disposed of, expect to add $500–$2,500 depending on the volume.
• Rim joists: Rim joist insulation is often priced separately and adds $500–$1,500 to a project, depending on linear footage and chosen material.
• Vapour barrier installation: If not included in the base quote, a professional vapour barrier installation adds approximately $0.50–$1.00 per sq ft.
• Access and complexity: Basements with irregular layouts, many obstacles, or limited access points take longer to insulate and may carry a labour premium.
• Location in Ontario: Labour costs vary by region. Expect to pay slightly more in Toronto and the GTA compared to smaller cities and rural areas.

Before finalizing your budget, factor in the Ontario and federal rebates that may be available to you. Basement insulation upgrades are eligible under several programs:

• Canada Greener Homes Grant: Up to $5,600 in grants for qualifying insulation upgrades, based on the results of a pre- and post-retrofit EnerGuide home energy audit. Basement insulation upgrades to R-20 or higher can qualify.
• Enbridge Home Efficiency Rebate Plus (HER+): Offers rebates on a range of insulation upgrades for Enbridge gas customers in Ontario, with amounts varying by upgrade type and home energy improvement achieved.
• Ontario Home Renovation Savings Program: Provides rebates for qualifying home energy efficiency upgrades through Save on Energy. Program terms and available rebate amounts change periodically.

Important: Most rebate programs require a pre-retrofit home energy audit by a registered energy advisor before work begins. Rebates cannot typically be claimed retroactively. Constant Home Comfort can help you understand which programs apply to your home and how to maximize your incentive eligibility before your project starts.

Looking purely at upfront cost, fiberglass batt is the winner. Looking at long-term energy savings, moisture durability, and air sealing performance, closed-cell spray foam often provides the best return on investment — especially in Ontario's harsh winters. Here's a practical framework for choosing:

• Lowest upfront budget: Fiberglass batt with vapour barrier — best for dry basements you plan to finish
• Best moisture performance: Closed-cell spray foam — ideal for basements with any moisture history
• Best balance of cost and performance: Rigid foam board (XPS) — widely used, code-compliant, and strong moisture resistance
• Best for sound and fire: Mineral wool batt — premium batt option that outperforms fiberglass in damp or noise-sensitive applications
• Highest energy savings potential: Closed-cell spray foam at 2"+ — maximizes R-value, eliminates air leakage, and qualifies for the highest rebate tiers

Want a free, no-obligation quote for your basement? Call Constant Home Comfort at 1 (888) 675-5907 or book your in-home assessment online. We serve homeowners across Toronto, the GTA, Hamilton, Ottawa, Barrie, and all of Ontario — and we'll help you identify every rebate you qualify for before work begins.

How much does it cost to insulate a basement in Ontario?

The total cost to insulate a typical Ontario basement ranges from approximately $1,500 on the low end (basic fiberglass batt installation) to $12,000 or more for a premium closed-cell spray foam installation. The most common mid-range projects — rigid foam board or open-cell spray foam — typically come in between $2,500 and $6,000 before rebates. Your final cost depends on your basement's size, wall condition, and the insulation type selected.

Is spray foam insulation worth the extra cost for a basement?

For most Ontario homeowners, yes — especially in basements with any history of moisture, high energy bills, or where maximizing rebate eligibility is a priority. Closed-cell spray foam provides the highest R-value per inch, doubles as a vapour and air barrier, and is extremely durable. While the upfront investment is higher, the long-term energy savings and reduced risk of moisture damage often make it the most cost-effective choice over a 10–20 year horizon.

Can I save money by insulating my basement myself?

DIY installation is possible with fiberglass batt or rigid foam board, and can reduce costs noticeably on materials versus professional installation. However, DIY installations may not qualify for rebate programs (which typically require professionally installed, code-compliant work), and mistakes in vapour management or air sealing can cause costly moisture problems down the line. Spray foam should always be professionally installed.

Do I need a vapour barrier with basement insulation in Ontario?

In most cases, yes — Ontario building code requires vapour control on the warm side of basement insulation. The exception is when using closed-cell spray foam at sufficient thickness, which itself acts as a Class II vapour retarder. For all batt and most rigid foam installations, a 6-mil polyethylene vapour barrier is required. Your installer will confirm what is needed for your specific assembly.

How do I get rebates for basement insulation in Ontario?

To access most rebate programs, you'll need to book a home energy audit with a registered energy advisor before your insulation work begins. The advisor assesses your home's current energy performance, recommends upgrades, and files the paperwork required to access provincial and federal incentive programs. Constant Home Comfort can connect you with the right energy advisor and guide you through the process from start to finish.

How long does a basement insulation project take?

Most standard basement insulation projects are completed within one to two days. Spray foam installations cure quickly and typically allow re-entry within 24 hours. Projects involving extensive surface preparation, removal of old insulation, or complex wall configurations may take an additional day. Your Constant Home Comfort advisor will provide a realistic timeline as part of your quote.