What is the average cost per square foot for insulation in NB? | Insulation IQ?

Insulation costs per square foot in New Brunswick vary considerably depending on the product type, the application area (attic, wall, basement, crawlspace), and site-specific conditions. There is no single universal rate, but understanding the typical ranges for each product and application gives you a useful benchmark when getting quotes from local contractors.

Blown-in cellulose or fibreglass in attics is the lowest cost per square foot for achieving high R-values in New Brunswick. Installed pricing typically runs $0.80 to $1.80 per square foot for a standard attic top-up to R-50 or R-60. A 1,000-square-foot attic in Moncton or Fredericton brought up to climate zone 6 recommendations would land in the $800 to $1,800 range before any air sealing work. This is the best dollar-per-R-value option available.

Fibreglass batt insulation in walls or open stud cavities during renovation runs $0.50 to $1.20 per square foot for the material and installation in new or open-wall construction. However, this assumes walls are open and accessible (during a renovation or new build). In retrofit situations where walls are intact, the cost of labour to install batts rises significantly or the project shifts to a different product altogether.

Blown-in fibreglass or cellulose in existing walls (dense-pack retrofit through drilled holes) typically costs $1.50 to $3.50 per square foot of wall area in New Brunswick. Dense-pack wall insulation involves drilling a series of holes in the exterior or interior cladding, filling each stud bay with dense-packed material under pressure, and patching the holes. The labour component is high relative to the amount of insulation installed, which is why wall retrofit costs per square foot are higher than attic work. For a typical New Brunswick two-storey home with 1,200 square feet of exterior wall, a full dense-pack retrofit might run $5,000 to $10,000 depending on cladding type and access conditions.

Open-cell spray foam runs $1.00 to $1.75 per square foot per inch of thickness installed. For an attic application at R-20 (roughly 3 inches), expect $3.00 to $5.25 per square foot. Open-cell foam is less expensive than closed-cell but provides lower R-value per inch and is not a vapour barrier — an important distinction in New Brunswick's cold climate zone 6 where vapour management matters.

Closed-cell spray foam is the premium option at $2.00 to $3.50 per square foot per inch of thickness. At its R-6 to R-7 per inch rating, two inches of closed-cell foam achieves approximately R-12 to R-14. For basement rim joists, crawlspace walls, or cathedral ceiling sections where depth is limited and maximum R-value per inch matters, closed-cell spray foam is frequently the right choice despite its higher cost. A typical rim joist spray foam project in a Saint John or Fredericton home might cover 200 to 300 linear feet and cost $800 to $2,500 for a thorough sealed application.

Rigid foam board (EPS, XPS, polyiso) installed on basement walls or as continuous exterior insulation runs $0.75 to $2.00 per square foot for material plus installation, depending on thickness and whether framing and drywall finishing is included. XPS (extruded polystyrene, typically blue or pink board) is very common in New Brunswick basements at 2-inch thickness for approximately R-10, often the minimum sensible investment for any conditioned basement space.

Mineral wool batts (Rockwool/Comfortbatt) for walls or between-joist basement applications run $1.20 to $2.50 per square foot installed, slightly more than fibreglass batts but with better fire resistance and acoustic performance, which makes them popular for inter-unit walls and floor assemblies.

When comparing quotes, make sure contractors are quoting to the same finished R-value rather than just the same product type — an attic quote to R-50 and a quote to R-60 are meaningfully different even at the same price per square foot. Also confirm whether air sealing is included or priced separately, as a thorough air sealing package under attic insulation in an older NB home adds $400 to $1,000 but is often more valuable than the additional inches of insulation on top.

For budget planning, New Brunswick homeowners can also factor in NB Power rebates and Efficiency NB programs that reduce effective net cost. Getting two or three quotes from insulation professionals is always worthwhile — New Brunswick Insulation and the New Brunswick Construction Network directory connect homeowners with experienced local contractors who can provide site-specific pricing.

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Looking for experienced contractors? The New Brunswick Construction Network connects homeowners with qualified professionals:

• Thirty Four Renovations
• 3Tone Construction Ltd
• Arctic Fox Construction Inc.
• Brunswick insulation & roofing
• Gionetterenovations