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

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

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

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

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

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Raised heel energy trusses extend past the exterior wall and are deeper at the wall allowing room for full insulation coverage over the top plate of the exterior walls.

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Design the roof with raised heel trusses to allow full insulation over the top plates of the exterior walls.

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In cathedral ceilings, parallel chord trusses allow thicker insulation levels over the exterior wall top plates.

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Standard roof trusses are narrow at the eaves, preventing full insulation coverage over the top plate of the exterior walls

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Right – This attic knee wall and the floor joist cavity openings beneath it are being sealed and insulated with spray foam.

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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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Attic Knee Walls

Guide

Guide describing how to insulate and air-seal attic knee walls and floor joist cavities under knee walls.

Attic Eave Minimum Insulation

Guide

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

Air Sealing and Insulating Ceilings in Vented Attics

Guide

Guide describing how to air-seal and insulate a ceiling where the insulation is installed on top of the ceiling (on the attic floor) in a vented attic.

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

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Install Top Plates or Blocking at the Top of Walls Adjoining Unconditioned Spaces

Guide

Guide describing how to correctly air-seal a wall with missing top plates or open wall cavities.

Below Deck Spray Foam Insulation for Existing Roofs

Guide

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.

Batt Insulation for Existing Vented Attics

Guide

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

Wrong – No rigid backing was installed on the attic knee wall.

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Blown Insulation for Existing Vented Attic

Guide

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

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

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Spray Foam Insulation Applied to Existing Attic Floor

Guide

Guide describing how to apply spray foam insulation to the floor of the attic in existing homes.

Limited attic access can make inspections for missing air barriers and insulation challenging

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Right - Continuous wall sheathing and blocking has been installed to brace the raised heel trusses.

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Limited attic access may make it necessary to use a bore scope when inspecting for missing air barriers and insulation in existing buildings.

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Right-- IR photo shows how effectively spray foam insulated/air sealed attic kneewall and the floor cavities under kneewall

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A 1- and ½-story home with a room located in the attic and the thermal boundary located at either a) the walls and ceiling of the attic room with small vented attic spaces or b) the roof line for an unvented attic

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

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

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

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

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

Raised heel energy trusses extend past the exterior wall and are deeper at the wall allowing room for full insulation coverage over the top plate of the exterior walls.

Design the roof with raised heel trusses to allow full insulation over the top plates of the exterior walls.

In cathedral ceilings, parallel chord trusses allow thicker insulation levels over the exterior wall top plates.

Standard roof trusses are narrow at the eaves, preventing full insulation coverage over the top plate of the exterior walls

Right – This attic knee wall and the floor joist cavity openings beneath it are being sealed and insulated with spray foam.

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.

Attic Knee Walls

Attic Eave Minimum Insulation

Air Sealing and Insulating Ceilings in Vented Attics

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

Install Top Plates or Blocking at the Top of Walls Adjoining Unconditioned Spaces

Below Deck Spray Foam Insulation for Existing Roofs

Batt Insulation for Existing Vented Attics

Wrong – No rigid backing was installed on the attic knee wall.

Blown Insulation for Existing Vented Attic

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

Spray Foam Insulation Applied to Existing Attic Floor

Limited attic access can make inspections for missing air barriers and insulation challenging

Right - Continuous wall sheathing and blocking has been installed to brace the raised heel trusses.

Limited attic access may make it necessary to use a bore scope when inspecting for missing air barriers and insulation in existing buildings.

Right-- IR photo shows how effectively spray foam insulated/air sealed attic kneewall and the floor cavities under kneewall

A 1- and ½-story home with a room located in the attic and the thermal boundary located at either a) the walls and ceiling of the attic room with small vented attic spaces or b) the roof line for an unvented attic

Dropped Ceiling/Soffit Below Unconditioned Attic

Air Sealing Drywall to Top Plate

DOE ZERH HIA 2017 Case Study: United Way of Long Island, United Veterans Beacon House, Huntington Station, NY