How much does it cost to insulate a 600 sq ft addition on a Riverview NB home including wall, attic, and floor insulation with permits?

A 600 sq ft addition in Riverview will typically cost $4,500-$9,500 for complete insulation including walls, attic, and floor, plus $300-$800 for building permits. The wide range depends on insulation types chosen, foundation design, and whether you're building over a basement, crawl space, or slab-on-grade.

Wall Insulation Costs
For a 600 sq ft addition, you're looking at roughly 400-500 sq ft of exterior wall area (assuming 8-foot ceilings). Standard 2x6 wall construction with R-22 fibreglass batts costs $600-$1,200 installed. Upgrading to mineral wool batts (Rockwool) adds $200-$400 but provides better moisture resistance and soundproofing — valuable in Riverview's humid Maritime climate. If you want premium performance, 2x6 walls with R-22 batts plus 2 inches of exterior rigid foam (XPS) for continuous insulation runs $1,800-$3,200 but eliminates thermal bridging and achieves true R-32 whole-wall performance.

Attic Insulation Costs
The 600 sq ft attic floor requires R-50 to R-60 under current NB Building Code. Blown-in cellulose or fibreglass to achieve R-60 costs $900-$1,800 installed. The key is proper air sealing before insulation — sealing all electrical penetrations, pot light housings, and the attic hatch. Many contractors skip this step, but it provides 50% of the energy benefit. Budget an extra $200-$500 for comprehensive attic air sealing, which is money extremely well spent in Riverview's 5,000+ heating degree day climate.

Floor Insulation Variables
Floor insulation costs depend entirely on your foundation type. Slab-on-grade requires R-10 perimeter insulation (2 inches of XPS around the slab edge) costing $400-$800. Full basement underneath means insulating the basement ceiling with R-31 batts ($600-$1,200) or insulating the basement walls instead with spray foam or rigid foam ($1,200-$2,500). Crawl space construction requires wall insulation plus vapour barrier on the ground — budget $800-$1,800 for proper crawl space encapsulation.

Permit Costs and Requirements
Building permits in Riverview run $300-$800 for a 600 sq ft addition, depending on complexity and whether you're adding electrical, plumbing, or HVAC. The insulation work itself doesn't require a separate permit, but it will be inspected as part of the overall building permit process. The inspector will verify R-values, vapour barrier placement (warm side of the assembly in NB's cold climate), and proper ventilation details.

Riverview-Specific Considerations
Riverview sits in the Petitcodiac River valley with high humidity year-round and significant temperature swings. Proper vapour barrier installation is critical — 6-mil polyethylene on the warm (interior) side of all exterior walls and ceiling assemblies, with all seams sealed and penetrations carefully detailed. Many addition projects in the area experience moisture problems because contractors rush the vapour barrier work or install it on the wrong side of the insulation.

Money-Saving Strategies
The most cost-effective approach for a Riverview addition is 2x6 construction with R-22 mineral wool batts in the walls, blown-in cellulose to R-60 in the attic, and appropriate floor insulation for your foundation type. This typically runs $4,500-$6,500 total. Adding exterior continuous insulation pushes costs toward $7,000-$9,500 but dramatically improves performance and comfort.

Rebate Opportunities
New additions may qualify for NB Power rebates if the entire home achieves improved energy performance through the Total Home Energy Savings Program. Consider getting an EnerGuide evaluation before construction to explore rebate eligibility — potential savings of $2,000-$5,000 on comprehensive energy upgrades.

When to Hire a Professional
All insulation work for a permitted addition should be done by professionals to ensure code compliance and proper building science. The inspector will verify R-values, vapour barrier continuity, and ventilation details. Poor insulation installation can fail inspection and require costly rework.

Need help finding experienced insulation contractors for your Riverview addition? New Brunswick Insulation can match you with local professionals who understand Maritime climate building science and NB code requirements.

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

• Arctic Fox Construction Inc.
• Thirty Four Renovations
• moose luxury painting
• Gionetterenovations
• Brunswick insulation & roofing