Spray foam insulation provides the highest R-value per inch of any insulation available, combined with a complete air seal in a single application. For Duluth homeowners, this makes it the ideal solution for specific areas where standard insulation underperforms. Spray foam excels in the hard-to-reach areas common in Duluth's victorian homes — rim joists, bonus rooms over garages, cantilevered floor sections, and knee walls where other insulation types sag, settle, or leave gaps.
RetroGreen uses both open-cell and closed-cell spray foam, selecting the right type for each application based on the needs of your Duluth home. Closed-cell foam (R-7 per inch) is our choice for rim joists, exterior-facing walls in crawl spaces, and any area with moisture exposure. Open-cell foam (R-3.7 per inch) is more cost-effective for interior applications like cathedral ceilings and bonus rooms. We recommend spray foam strategically rather than as a whole-house solution — it delivers the most value when targeted at specific problem areas.
local utility rebates may apply to qualifying spray foam insulation — call us for current eligibility in Duluth homes. Our free diagnostic assessment identifies exactly where spray foam will make the biggest difference in your home's comfort and efficiency. Call (218) 414-7775 to schedule your visit.
Key Benefits
Highest R-Value Per Inch
Closed-cell spray foam delivers R-6.5 to R-7 per inch — nearly double traditional insulation. This means better performance in less space, critical for retrofit applications.
Complete Air Seal Built In
Unlike batt or blown-in insulation, spray foam seals air leaks as it insulates. No separate air sealing step needed. This dual function is why spray foam consistently outperforms other insulation types.
Moisture Barrier Protection
Closed-cell spray foam acts as a Class II vapor retarder, preventing moisture migration and condensation in wall and roof assemblies. It manages moisture and insulates in one application.
Structural Reinforcement
Closed-cell spray foam adds measurable racking strength to wall assemblies. It bonds structural components together, improving overall rigidity — a bonus in addition to its thermal performance.
Common Duluth Home Types We Insulate
Victorian
1890s-1920s mining and shipping eraCommon in East Hillside, Lincoln Park
Victorian homes common in Duluth from the 1890s-1920s mining and shipping era era are excellent candidates for spray foam insulation upgrades.
Craftsman bungalow
1890s-1920s mining and shipping eraCommon in East Hillside, Lincoln Park
Craftsman bungalow homes common in Duluth from the 1890s-1920s mining and shipping era era are excellent candidates for spray foam insulation upgrades.
Foursquare
1890s-1920s mining and shipping eraCommon in East Hillside, Lincoln Park
Foursquare homes common in Duluth from the 1890s-1920s mining and shipping era era are excellent candidates for spray foam insulation upgrades.
Our Process in Duluth
Site Assessment and Preparation
We evaluate the space, determine the optimal open-cell vs. closed-cell application, and calculate target R-values. Surfaces not being insulated are protected. Proper ventilation is established for the installation process.
Professional Spray Foam Application
Certified technicians apply spray foam using calibrated, temperature-controlled equipment. The foam expands to fill cavities completely, bonding to surfaces and sealing every gap. Multiple passes build to the desired thickness.
Trimming, Inspection, and Completion
Excess foam is trimmed for a clean, uniform surface. Thickness is verified with measurement tools at multiple points. We walk you through the completed work and answer any questions about your new insulation.