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Air Sealing, Insulating, and Venting Attics and Roofs to Reduce Heat Gain

Information Guide

Information guide providing links to guides describing specific ways to air-seal, insulate, and ventilate attics and roofs to minimize heat gain in new and existing homes.

Insulate and air seal the shaft around a skylight in a vented attic

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Right – The backing on this knee wall was air sealed prior to insulation.

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Building America Top Innovations 2013: Attic Air Sealing Guidelines

Reference

Fact sheet describing research sponsored by DOE's Building America program to research the importance of attic air-sealing and best practice attic air-sealing techniques for new and existing homes.

Air seal the attic access pull-down stairs opening with weatherstripping.

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Air sealing at interior wall between conditioned space and unconditioned attic

CAD File

Building Science for Dry Climates 5 - Building Shell, Air Sealing, & Attics

Presentation

Presentation by Home Performance Contractor Academy giving building science advice for for homes in dry climate zones, specifically building envelope, air sealing, and attics. Part 5 of 7.

Spray foam insulates and air seals the underside of the attic roof and walls.

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Wrong – The backing on this knee wall was not air sealed prior to adding insulation.

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Duct boots and other ceiling penetrations are air-sealed using spray foam

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Right – Several potential sources of air leakage into the attic have been air sealed; canned spray foam was used to seal around duct boots, along seams in the drywall, and along top plates.

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How to air seal attic can lights – Rule Your Attic! with ENERGY STAR

Video

Video describing how homeowners can save energy by air sealing their home's attic can lights.

How to air seal attic electrical boxes – Rule Your Attic! With ENERGY STAR

Video

Video describing how homeowners can save energy by air sealing their home's attic electrical boxes.

How to air seal attic plumbing pipe – Rule Your Attic! with ENERGY STAR

Video

Video describing how homeowners can save energy by air sealing their home's attic plumbing pipes.

Wrong – The batt insulation on this knee wall is not properly supported and there is no air sealed rigid backing to provide a solid air barrier.

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Spray foam insulates and air-seals the ceiling deck and top plates of this vented attic.

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The baffle is air sealed in place with spray foam before installing fiberglass or cellulose insulation

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Examples of many common ceiling penetrations that will be difficult to insulate and air seal in this cathedral ceiling.

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Weatherstripping has been installed along the framing of this attic access panel to air seal the opening.

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Weatherstripping has been installed along the edge of this attic access panel to air seal the opening.

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Spray foam insulation insulates and air seals around plumbing pipes and top plates in the attic.

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One way to air seal and insulate kneewalls – add insulation and a rigid air barrier along roof line of unconditioned attic space outside kneewall

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Right - Blocking has been installed between the ceiling joists and air sealed in place with canned spray foam to stop air flow beneath the attic knee wall.

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Caulk around the trim of the attic access panel or door to improve the air sealing between the living space and the attic.

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After all holes through the ceiling are air-sealed and the baffles have been installed, then the insulation can be installed.

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Latches were added to this attic access panel to hold it more tightly against the weatherstripping for better air sealing when closed.

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Air Sealing, Insulating, and Venting Attics and Roofs to Reduce Heat Gain

Insulate and air seal the shaft around a skylight in a vented attic

Right – The backing on this knee wall was air sealed prior to insulation.

Building America Top Innovations 2013: Attic Air Sealing Guidelines

Air seal the attic access pull-down stairs opening with weatherstripping.

Air sealing at interior wall between conditioned space and unconditioned attic

Building Science for Dry Climates 5 - Building Shell, Air Sealing, & Attics

Spray foam insulates and air seals the underside of the attic roof and walls.

Wrong – The backing on this knee wall was not air sealed prior to adding insulation.

Duct boots and other ceiling penetrations are air-sealed using spray foam

Right – Several potential sources of air leakage into the attic have been air sealed; canned spray foam was used to seal around duct boots, along seams in the drywall, and along top plates.

How to air seal attic can lights – Rule Your Attic! with ENERGY STAR

How to air seal attic electrical boxes – Rule Your Attic! With ENERGY STAR

How to air seal attic plumbing pipe – Rule Your Attic! with ENERGY STAR

Wrong – The batt insulation on this knee wall is not properly supported and there is no air sealed rigid backing to provide a solid air barrier.

Spray foam insulates and air-seals the ceiling deck and top plates of this vented attic.

The baffle is air sealed in place with spray foam before installing fiberglass or cellulose insulation

Examples of many common ceiling penetrations that will be difficult to insulate and air seal in this cathedral ceiling.

Weatherstripping has been installed along the framing of this attic access panel to air seal the opening.

Weatherstripping has been installed along the edge of this attic access panel to air seal the opening.

Spray foam insulation insulates and air seals around plumbing pipes and top plates in the attic.

One way to air seal and insulate kneewalls – add insulation and a rigid air barrier along roof line of unconditioned attic space outside kneewall

Right - Spray foam insulation air-seals the ceiling-to-drywall seams at the wall top plate.

Right - Closed-cell spray foam covers the ceiling and joists to insulate and air-seal the ceiling deck.

Cost Analysis of Roof-Only Air Sealing and Insulation Strategies on 1 1/2-Story Homes in Cold Climates

Air seal floor joist cavities under kneewall with rigid foam, plywood, or OSB caulked in place

Right - Blocking has been installed between the ceiling joists and air sealed in place with canned spray foam to stop air flow beneath the attic knee wall.

Caulk around the trim of the attic access panel or door to improve the air sealing between the living space and the attic.

After all holes through the ceiling are air-sealed and the baffles have been installed, then the insulation can be installed.

Latches were added to this attic access panel to hold it more tightly against the weatherstripping for better air sealing when closed.