BASC Search | Building America Solution Center

Duct insulated with a minimum of R-8 insulation

Publication Date

Thu, 08/01/2013 - 12:00

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

DWG

PDF

Attic Hatch Insulation

Publication Date

July, 2015

Author(s)

EnergySmartSolutions.org

Organization(s)

EnergySmartSolutions.org

Video describing how to properly insulate attic hatches.

Unvented Attic Insulation

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

Measure the depth of insulation

Publication Date

Fri, 01/01/2010 - 12:00

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

DWG

PDF

Insulation Below Attic Platforms

Guide describing how to install insulation below attic platforms

Attic Eave Minimum Insulation

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

Unvented Attic Insulation (2)

Publication Date

July, 2015

Video describing how to spray foam unvented attics.

Unvented Attic Insulation (1)

Publication Date

July, 2015

Video describing how to spray foam unvented attics.

How to Install Cellulose Insulation

Author(s)

Holladay Martin

Organization(s)

Green Building Advisor,

GBA

Publication Date

March, 2011

Information sheet presenting techniques for installing cellulose insulation.

Ducts Buried in Attic Insulation

Guide describing buried ducts in loose-fill attic insulation, a method that can only be used in dry climates.

Unvented Insulated Sloped Roofs

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

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

Batt insulation is installed in two layers in perpendicular directions against the baffle to full required insulation height

Publication Date

Thu, 09/10/2015 - 12:00

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.

Blown Insulation for Existing Vented Attic

Guide describing how to insulate a vented attic in an existing home using blown insulation added to the attic floor.

Attic Eave Minimum Insulation (3)

Publication Date

July, 2015

Video describing raised heel trusses for minimum attic eave insulation.

Installation of Cavity Insulation, Info-501

Author(s)

Building Science Corporation

Organization(s)

BSC

Publication Date

May, 2009

Article explaining installing cavity insulation.

Attic Eave Minimum Insulation (1)

Publication Date

July, 2015

Video describing how to install batt insulation.

Attic Eave Minimum Insulation (2)

Publication Date

July, 2015

Video describing how to properly insulate attic eaves.

The Truth about insulation in a hot climate

Publication Date

March, 2019

Author(s)

Horizon Energy

Organization(s)

Horizon Energy

Video from Horizon Energy on thermodynamics relating to insulation in attics of homes located in hot climates.

Ducts Buried in Attic Insulation and Encapsulated

Guide describing approaches to burying and encapsulating ducts in unconditioned attics to increase the overall R-value of duct insulation.

Batt insulation is installed at the attic floor

Publication Date

Thu, 09/10/2015 - 12:00

Batt insulation is installed in two layers with offset seams against the baffle to full code-required insulation height

Publication Date

Thu, 09/10/2015 - 12:00

Wrong – Insulation will not be aligned with air barrier

Publication Date

Fri, 10/28/2011 - 12:00

Right - The underside of the attic roof deck is insulated with open-cell spray foam to provide an insulated space for HVAC equipment.

Publication Date

Fri, 01/01/2010 - 12:00

Right - The attic access panel is insulated and weather stripped and a dam is built to hold back the blown attic floor insulation

The attic kneewall and the open floor cavities under kneewall are both sealed and insulated in one step with spray foam insulation

Publication Date

Tue, 12/01/2009 - 12:00

Right – Spray foam insulates the unvented attic.

Publication Date

Mon, 09/30/2019 - 12:00

Wrong - This attic access hatch cover is not insulated

Wrong – The framing will not allow for required insulation depth.

Publication Date

Fri, 10/28/2011 - 12:00

Right – The framing allows for required insulation depth.

Publication Date

Fri, 10/28/2011 - 12:00

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

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.

Spray Foam Insulation Applied to Existing Attic Floor

Guide describing how to apply spray foam insulation to ceilings in existing homes.

Ducts Encapsulated in Spray Foam and Buried in Attic Insulation

Publication Date

September, 2015

Video describing various ways to bring HVAC ducts installed in an attic within the thermal envelope of the home by insulating the attic or by covering the ducts with spray foam and burying them in fibrous insulation.

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.

Right - This attic catch cover is insulated with rigid foam

Right – The knee wall is properly insulated and air sealed.

Publication Date

Fri, 10/28/2011 - 12:00

The enhanced comfort attic insulation consists of an ultra-efficient 25-inch-thick layer of blown cellulose providing a substantial R-90 insulation value.

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

Publication Date

Mon, 11/01/1999 - 12:00

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.

Sealing and Insulating Existing Vented Attics - Code Compliance Brief

Publication Date

May, 2016

The intent of this brief is to provide code-related information about sealing and insulating existing vented attics to help ensure that the measure will be accepted as being in compliance with the code. Providing the same information to all interested parties (e.g., code officials, builders, contractors, designers, etc.) is expected to result in increased compliance and fewer innovations being questioned at the time of plan review and/or field inspection.

Protect Your Family from Asbestos - Contaminated Vermiculite Insulation

Author(s)

U.S. Environmental Protection Agency

Organization(s)

EPA

Publication Date

January, 2015

This page provides important information on how to protect yourself and your family if you suspect that you might have vermiculite insulation from Libby, Montana.

Spray foam insulation used for raised ceiling duct chase

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

Building America Energy Performance Brief: Insulating Attic Kneewalls

Author(s)

Gilbride Theresa L

Organization(s)

PNNL

Publication Date

March, 2011

Case study describing the options and techniques one should consider when trying to insulate attic knee walls in order to reduce air leakage.

Right – Baffles maintain air flow above attic insulation

1 inch exterior insulation sheathing as attic eave baffle and vent

DWG

PDF

Right – HVAC platform installed to allow for proper insulation depth

Publication Date

Fri, 10/28/2011 - 12:00

Right – Insulation installed to correct depth and will be aligned with air barrier

Publication Date

Fri, 10/28/2011 - 12:00

Install insulation under platforms constructed in the attic for storage or equipment.

Publication Date

Fri, 10/28/2011 - 12:00

Install an air barrier on the exterior of attic knee wall insulation.

Publication Date

Fri, 10/28/2011 - 12:00

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

Publication Date

Fri, 10/28/2011 - 12:00

Air seal and insulate drawer and closet boxes in attic kneewalls

Reference

Retrofit Techniques and Technologies: Air Sealing, Volume 10

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Williamson Jennifer,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

Report identifying the steps to take, with the help of a qualified home performance contractor, to seal unwanted air leaks while ensuring healthy levels of ventilation and avoiding sources of indoor air pollution.

Publication Date

Mon, 04/12/2010 - 12:00

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.

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

2009-2021 IECC and IRC Minimum Insulation Requirements for New Homes

Table adapted from Table R402.1.1 in the 2009 and 2012 IECC and Table R402.1.2 in the 2015 and 2018 IECC (Table N1102.1 in 2009 IRC, Table 1102.1.1 in 2012 IRC, and Table N1102.1.2 in 2015 and 2018 IRC).

Application of Spray Foam Insulation Under Plywood and OSB Roof Sheathing

Publication Date

July, 2015

Video describing how to air seal attic rafters with spray foam.

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

Air Sealing and Insulating Attic Knee Walls - Code Compliance Brief

Air sealing and insulating attic knee walls to code.

Why Are Attics Insulated With Open-Cell Spray Foam So Damp?

Author(s)

Holladay

Organization(s)

Green Building Advisor

Presentation describing issues with condensation in unvented attics insulated with open-cell spray foam.

The attic duct chase insulated and sealed to the attic floor with spray foam

Imagine Homes chose low-density spray foam to insulate this attic.

Publication Date

Thu, 09/01/2011 - 12:00

Right: Ducts are completely buried beneath insulation to the depth specified in the plans

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

Publication Date

Thu, 09/01/2011 - 12:00

Right - A wood dam was constructed to hold back the attic floor insulation

Wrong – The framing and wind baffle installation will not allow for required insulation depth.

Publication Date

Fri, 10/28/2011 - 12:00

Wrong – Drop down stairs do not have insulation cover installed

Publication Date

Fri, 10/28/2011 - 12:00

Wrong – Attic access panel does not have an insulation cover installed

Publication Date

Fri, 10/28/2011 - 12:00

A standard site-built roof of rafters may pinch the insulation at the eaves

Publication Date

Sat, 01/01/2011 - 12:00

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

Publication Date

Fri, 10/28/2011 - 12:00

Right – Rigid backing was installed prior to insulating the attic knee walls.

Publication Date

Fri, 10/28/2011 - 12:00

Right – Top and bottom plates were installed prior to backing and insulation.

Publication Date

Fri, 10/28/2011 - 12:00

Wrong: Ducts are held above the ceiling plane with strapping to provide a good angle into top-entry boots. Once the ceiling insulation is added, this duct will protrude from the ceiling insulation and will not be buried

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

Right- This flue pipe has been air sealed with sheet metal and fire-rated caulk and an insulation dam has been constructed to keep insulation from touching the hot flue pipe

1 inch rigid insulation as attic eave baffle cut around manufactured vent

DWG

PDF

Wrong – No blocking installed to prevent attic insulation from falling into stairs and opening

Publication Date

Fri, 10/28/2011 - 12:00

This attic was insulated with 5 inches of closed-cell spray foam on the underside of the roof deck plus 6.5 inches of blown fiberglass covered with sheetrock as a firebreak for a total R-58 roof assembly insulation value.

Right – Spray foam air seals and insulates the walls including the walls behind the fireplace and covers the underside of the roof deck of this mixed-dry climate home to provide an insulated attic space for HVAC ducts.

Publication Date

Thu, 09/30/2021 - 12:00

The attic knee walls were constructed from 2x6s and insulated with R-19 batt, backed with 1 inch of XPS foam board with taped joints to provide a solid air barrier over the insulated surfaces.

Publication Date

Thu, 08/17/2023 - 12:00

How to measure your attic’s insulation level – Rule Your Attic! with ENERGY STAR

Publication Date

October, 2015

Video describing how homeowners can measure the amount of insulation installed in their attic.

Lstiburek

Organization(s)

Pacific Northwest National Laboratory,

Building Science Corporation,

BSC

Webinar explaining new code options for insulating, sealing, and controlling moisture in unvented attics in residential buildings.