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Faced vs unfaced insulation in attic: which fits your climate?
Choose Faced batt insulation for an attic floor in IECC Climate Zones 5 and 6, laid with the facing against the attic floor (DOE, 2012); Unfaced batt insulation for an attic floor in IECC Climate Zones 1 through 4 (DOE, 2012).
The right choice depends on your climate zone on the International Energy Conservation Code (IECC) map, whether you are adding a layer over batts already in the attic, and whether the batts would touch a chimney, flue pipe or recessed light fixture.
| Factor | Faced batt insulation | Unfaced batt insulation |
|---|---|---|
| An attic floor in IECC Climate Zones 5 and 6, laid with the facing against the attic floor (DOE, 2012) | the type DOE's guide says to install there, with the facing against the attic floor | DOE's same list names unfaced batts for IECC Climate Zones 1 through 4 |
| An attic floor in IECC Climate Zones 1 through 4 (DOE, 2012) | Building America scientists do not recommend vapor retarders in vented attics in these zones (2006 research) | the type DOE's guide says to use there |
| Adding a new layer over batts already in the attic (DOE, 2012) | a facing between the layers can act as a vapor retarder and create problems with moisture and mold | DOE says there should be no facing between the layers |
| Batts near a chimney, flue pipe or recessed light fixture (DOE, 2012) | kraft-paper facing should not be placed in contact with them | fiberglass itself is noncombustible, but the resin binders it contains are combustible |
| Vapor retarder class in DOE's table (perm = how much water vapor a layer lets through) | kraft-faced fiberglass batts: Class II, greater than 0.1 perm to less than 1.0 perm | no official figure |
| Vented attics in Climate Zone 6 and up (DOE Building America Solution Center, 2020 research) | needs at least a Class II vapor retarder; kraft-faced fiberglass batts are one option, beside a smart membrane vapor barrier or vapor barrier paint | no official figure |
| Reading the R-value of batts already in your attic (DOE, 2012) | the R-value will often be printed on the facing | measure the depth with a ruler and estimate the R-value from DOE's table |
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- MCP connector URL
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https://instabids.ai/openapi.json - Start-request link
https://instabids.ai/intake?from=options-compare--faced-vs-unfaced-insulation&utm_source=us&utm_medium=page&utm_campaign=options&page_type=options#job=attic%20insulation - Prompt for any AI, with your job
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Every page is plain HTML. Steps for every assistant: add to your assistant.
| Priority | Choose |
|---|---|
| your attic is in IECC Climate Zone 5 or 6 (DOE, 2012) | Faced batt insulation |
| your attic is in IECC Climate Zones 1 through 4 (DOE, 2012) | Unfaced batt insulation |
| you are adding a layer over batts already in the attic (DOE, 2012) | Unfaced batt insulation |
What does attic insulation cost?
For attic insulation prices, see How much does attic insulation cost?
Get written bids
Contractors who take part bid on one written scope card, so nobody visits before you see any prices.
The contractor you pick may visit once before settling the final price against the percentage the bid stated.
Contact details stay hidden until the homeowner picks a contractor and they confirm the connection.
The contact-detail filter can miss disguised contact details.
Sources for the facts on this page
- U.S. DOE Building America Best Practices Series Vol. 17, Energy Renovations: Insulation (PNNL-20972, prepared by Pacific Northwest and Oak Ridge National Laboratories, May 2012), government, read 22 October 2026.
- U.S. DOE Building America Solution Center (Pacific Northwest National Laboratory), Attic Air Sealing, Insulating, and Ventilating for Ice Dam Prevention, national laboratory, read 22 October 2026.