InstaBidsFor homeowners
Spray foam vs blown insulation: which one fits your home?
It depends on the job: Spray foam suits cold climates that require more protection from condensation, with closed-cell spray foam. The right choice depends on protection from condensation, wall retrofits, and R-value per inch.
| Factor | Spray foam | Blown-in loose-fill insulation |
|---|---|---|
| Air barrier | DOE (2012), open-cell and closed-cell spray foam: "Both will provide a good air barrier." | no official figure |
| cold climates that require more protection from condensation, with closed-cell spray foam | DOE (2012), closed-cell: "spray foam is also a vapor retarder, an advantage in cold climates that require more protection from condensation." | DOE (2012): "To avoid moisture problems, be sure that blown insulation does not cover attic eave vents." |
| Open-cell vapor behavior | DOE (2012): "Open-cell foam is not a vapor retarder." | no official figure |
| Closed-cell moisture behavior | DOE (2012), closed-cell medium-density polyurethane spray foam: "Very resistant to moisture." | no official figure |
| Foam installation | DOE (2012), open-cell and closed-cell polyurethane spray foam: "Installation difficult." | no official figure |
| Retrofits | no official figure | DOE (2012), blown-in loose-fill fiber: well suited "for retrofits." |
| Loose-fill equipment | no official figure | DOE (2012), blown-in loose-fill fiber: must be applied using an "insulation blowing machine." |
| Wall retrofits | no official figure | DOE (2012): for wall retrofits, requires drilling of wall sheathing to "gain access to wall cavities." |
| Closed-cell R-value per inch | DOE (2012), closed-cell medium-density polyurethane spray foam: "R-7 to R-9" per inch. | no official figure |
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MCP connector · REST API · plain HTMLHand any of these to your assistant and it can help you write this job's request; you send the request yourself. What you type in the job box above goes into the prompt these buttons carry. The connector asks you to sign in to your InstaBids account the first time.
- MCP connector URL
https://instabids.ai/api/agent/mcp - Agent API (OpenAPI)
https://instabids.ai/openapi.json - Start-request link
https://instabids.ai/intake?from=options-compare--spray-foam-vs-blown-insulation&utm_source=us&utm_medium=page&utm_campaign=options&page_type=options#job=spray%20foam%20or%20blown-in%20loose-fill%20insulation%20installation - Prompt for any AI, with your job
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- GeminiCopies the prompt, then opens
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Get written bids
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Sources for the facts on this page
- U.S. Department of Energy, Energy Renovations: Insulation (May 2012), government, read 23 October 2026.