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Conceptual insulation at cape-style roof - roof cavity insulation with rigid insulation closure

Guide describing methods for insulating an unvented attic along the roof line.

Conceptual insulation at cape-style roof - ceiling and knee wall cavity insulation

DWG

PDF

Attic Eave Minimum Insulation

Guide providing guidance on insulating attic eaves in new and existing single-family homes and multifamily buildings.

Unvented Insulated Sloped Roofs

Guide describing construction of sloped roofs that are unvented and are insulated above the roof deck.

Batt Insulation for Existing Vented Attics

Guide describing how to increase insulation in existing homes by installing batt insulation on the ceiling plane of a vented attic.

Detail of an unvented cathedralized attic showing air-impermeable spray foam insulation plus batt insulation installed on the underside of the roof deck.

Right – Battens were installed above the cork insulation to provide a ventilating layer between the insulation and the roof sheathing on this “hot roof” design.

Publication Date

Mon, 09/30/2019 - 12:00

Above Deck Rigid Foam Insulation for Existing Roofs

Guide describing the installation of insulating sheathing above the roof deck on existing homes. This retrofit assembly is appropriate for homes with conditioned attics or where the retrofit is intended to create a conditioned attic.

Below Deck Spray Foam Insulation for Existing Roofs

Guide describing how to add spray foam insulation to the underside of the existing roof deck as part of the conversion of a vented attic to an unvented, insulated attic.

Attic Retrofits Using Nail-Base Insulated Panels

Author(s)

Mallay David,

Kochkin Vladimir

Organization(s)

U.S. Department of Energy,

DOE,

Home Innovation Research Labs,

HIRL

Publication Date

March, 2018

This report outlines research activities that are expected to facilitate the adoption of energy retrofits by remodeling contractors and roofing contractors using retrofit panels which applicable to many existing house designs in most climates and markets.

2x4 Raised Truss - Insulation Below Roof Deck CAD

DWG

PDF

Attic Air Sealing, Insulating, and Ventilating for Ice Dam Prevention

Information guide describing proper attic air-sealing, insulation, and ventilation to combat ice dam formation on roofs in cold climate zones.

Wrong - The roof insulation panels for this building were not installed in multiple layers with joints offset. The snow melt pattern shows thermal bypasses at the insulation panel joints.

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

Right – Baffles maintain air flow above attic insulation

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

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.

Roofing membrane is installed over polyisocyanurate rigid foam insulation and insulation cover board that has been cut to fit around locations for blocking for the PV system rack

Right - Spray foam insulation has been sprayed onto the underside of the sloped roof and the gable end wall to provide a sealed, insulated attic for housing the HVAC ducts

Rigid Foam Insulation Installed Between Existing House and Garage Walls

Guide describing how to upgrade walls that separate the garage from the house by providing a continuous air control layer on the garage side of the wall and adding rigid foam insulation.

To reduce the risk of condensation on the interior of the roof sheathing in cold weather, the ratio of exterior (above-deck) insulation must be increased as a percent of total attic insulation as outside temperature decreases

Publication Date

Sat, 10/01/2011 - 12:00

Traditional roof trusses pinch insulation where the roof meets the walls.

Publication Date

Thu, 09/01/2011 - 12:00

2x10 Rafter - Insulation Above Roof Deck and In Rafter Cavity CAD

DWG

PDF

2x10 Rafter - Insulation Below Roof Deck In Rafter Cavity CAD

DWG

PDF

2x12 Rafter - Insulation Above Roof Deck and In Rafter Cavity CAD

DWG

PDF

2x12 Rafter - Insulation Below Roof Deck In Rafter Cavity CAD

DWG

PDF

Water Managed Roof – Re-roofing and Adding Insulation Over a Sloped Roof

Guide describing how to re-roof an existing home with a sloped and add insulation above the roof deck.

Water Managed Roof – Re-roofing and Adding Insulation over a Flat Roof

Guide describing an approach to re-roofing an existing flat roof to improve thermal, water, and air control performance.

Right – The underside of this low-sloped roof is insulated with open-cell spray foam in this dry climate to achieve the code-required R-value; the builder used the same foam to insulate exterior walls.

Publication Date

Fri, 12/31/2021 - 12:00

How To Strengthen Your Home for Under $10,000 – Insulated Concrete Forms

Publication Date

September, 2014

Video interview explaining the benefits of installing insulated concrete forms for both energy efficiency and disaster resistance in either new or existing homes for under $10,000. Recommendations from FLASH Strong Homes.

Air sealing wall between a porch roof and attic with 1 inch of rigid insulation

Right - These roof insulation panels are installed in multiple layers with joints offset both vertically and horizontally. The plywood nail base fastened to the roof framing holds the insulation layers together snuggly thus minimizing gaps

Technology Solutions Case Study: Field Testing an Unvented Roof with Fibrous Insulation and Tiles

Author(s)

Building Science Corporation

Organization(s)

BSC

Publication Date

February, 2016

Case study describing field testing of an unvented roof with fibrous insulation and tiles.

Right - Raised-heel roof trusses allow more room at the eaves for attic insulation.

Sloped roof with cavity spray foam insulation, strapping, and gypsum board thermal barrier

Publication Date

Fri, 05/01/2015 - 12:00

A typical Las Vegas hot-dry climate home made of wood frame construction and insulated with R-25 expanded polystyrene externally over a drainage plane, with an unvented wood frame insulated attic and roof assembly.

Publication Date

Tue, 02/16/2010 - 12:00

Some builders use cantilevered trusses to get full height insulation over the exterior wall.

Publication Date

Sat, 09/01/2001 - 12:00

2021 IECC Climate Zone 4C: Vented Attic, 2x4 Wall, Interior Insulated Basement

Publication Date

Sat, 01/13/2024 - 12:00

2021 IECC Climate Zone 5A: Vented Attic, 2x4 Wall, Interior Insulated Basement

Publication Date

Mon, 01/15/2024 - 12:00

2021 IECC Climate Zone 5B: Vented Attic, 2x4 Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5C: Vented Attic, 2x4 Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 6A: Vented Attic, 2x4 Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 6B: Vented Attic, 2x4 Wall, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

2021 IECC Climate Zone 4C: Vented Attic, Strapped 2x6, Interior Insulated Basement

Publication Date

Mon, 01/15/2024 - 12:00

2021 IECC Climate Zone 5B: Vented Attic, Strapped 2x6, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5A: Vented Attic, Strapped 2x6, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5C: Vented Attic, Strapped 2x6, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 6A: Vented Attic, Strapped 2x6, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

2021 IECC Climate Zones 7 and 8: Vented Attic, Strapped 2x6, Interior Insulated Basement

Publication Date

Thu, 01/25/2024 - 12:00

2021 IECC Climate Zone 6B: Vented Attic, Strapped 2x6, Interior Insulated Basement

Publication Date

Thu, 01/25/2024 - 12:00

2021 IECC Climate Zones 7 and 8: Vented Attic, 2x4 Wall, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

2021 IECC Climate Zone 5: Vented Attic, 2x4 Wall, Interior Insulated Basement

Publication Date

Thu, 10/19/2023 - 12:00

Rigid foam insulation is installed on the garage side of the shared garage wall and roof of an existing home

Publication Date

Mon, 07/01/2013 - 12:00

This roof was insulated above the roof deck with 5.5 inches (R-38.5) of closed-cell spray foam.

Polyisocyanurate rigid foam insulation is installed in multiple layers with staggered, taped seams over the flat roof

2021 IECC Climate Zone 6: Vented Cathedral ceiling, 2x6 Wall, interior Insulated Basement

Publication Date

Thu, 10/19/2023 - 12:00

2021 IECC Climate Zone 5: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement

Publication Date

Thu, 10/19/2023 - 12:00

2021 IECC Climate Zone 4C: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement

Publication Date

Sat, 01/13/2024 - 12:00

2021 IECC Climate Zone 4C: Vented Attic, Exterior Double Wall, Interior Insulated Basement

Publication Date

Mon, 01/15/2024 - 12:00

2021 IECC Climate Zone 5A: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5A: Vented Attic, Exterior Double Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5B: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5B: Vented Attic, Exterior Double Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5C: Vented Attic, Exterior Double Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 6A: Vented Attic, Exterior Double Wall, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

2021 IECC Climate Zone 6B: Vented Attic, Exterior Double Wall, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

2021 IECC Climate Zones 7 and 8: Vented Attic, Exterior Double Wall, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

2021 IECC Climate Zone 4C: Vented Attic, Interior Double Wall, Interior Insulated Basement

Publication Date

Mon, 01/15/2024 - 12:00

2021 IECC Climate Zone 5A: Vented Attic, Interior Double Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5B: Vented Attic, Interior Double Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 5C: Vented Attic, Interior Double Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 6B: Vented Attic, Interior Double Wall, Interior Insulated Basement

Publication Date

Thu, 01/25/2024 - 12:00

2021 IECC Climate Zones 7 and 8: Vented Attic, Interior Double Wall, Interior Insulated Basement

Publication Date

Thu, 01/25/2024 - 12:00

2021 IECC Climate Zone 5C: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement

Publication Date

Tue, 01/16/2024 - 12:00

2021 IECC Climate Zone 6A: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

2021 IECC Climate Zones 7 and 8: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

2021 IECC Climate Zone 6B: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement

Publication Date

Wed, 01/17/2024 - 12:00

Ice dams formed by melting of snow on roofs can affect roofs, walls, ceilings, siding, and insulation.

Publication Date

Mon, 02/04/2013 - 12:00

Right - Raised-heel trusses increase the roof height above the eaves allowing more space for insulation above exterior wall top plates; exterior wall sheathing extends up to keep wind from soffit vents from disrupting insulation.

Flat roof with cavity spray foam plus loose-fill insulation and gypsum board thermal barrier.

Publication Date

Fri, 05/01/2015 - 12:00

Spray foam insulation was installed on the underside of the roof deck and on gable end attic walls to create an unvented attic

Publication Date

Fri, 10/15/2021 - 12:00

2021 IECC Climate Zone 4C: Vented Attic, 2x4 Wall, Interior Insulated Basement (with notes)

Organization(s)

BSC

Publication Date

November, 2013

Case study describing research about spray foam roof insulation and moisture management.

2021 IECC Climate Zone 5: Vented Attic, 2x4 Wall, Interior Insulated Basement (with notes)

Publication Date

Thu, 10/26/2023 - 12:00

The base of the plywood parapet is air sealed with spray foam and fibrous insulation is installed in the rafter cavities in this flat roof retrofit

Insulating sheathing is extended up to the roof rafters and sealed around the framing with spray foam as part of this exterior wall retrofit

2021 IECC Climate Zone 7 and 8: Vented Cathedral Ceiling, 2x6 Wall, Interior Insulated Basement (with notes)

Vented roof assembly at rake retrofitted with spray foam and additional insulation installed at the attic floor and extended to the rake edge

Publication Date

Mon, 07/01/2013 - 12:00