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

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

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

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.

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.

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.

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.

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

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.

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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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.

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.

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Right - These attic knee walls are insulated with rigid foam and sealed with spray foam to form a continuous air barrier at the gable end of this cathedral ceiling.

Right - These attic knee walls are insulated with rigid foam and sealed with spray foam to form a continuous air barrier at the gable end of this cathedral ceiling.

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

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

CAD File

Attic Knee Walls

Guide

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

Walls Adjoining Porch Roof

Guide

This guide describes how to install a rigid air barrier to separate the porch attic from the conditioned space.

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.

Roof/Attic to Exterior Wall Air Control Upgrade

Guide

Guide describing how to retrofit an exterior wall and/or attic to provide continuous air sealing.

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

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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Unvented Attic Insulation

Guide

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

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.

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

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

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

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

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Conceptual insulation practice at attic-style truss system - above unconditioned space

CAD File

Conceptual insulation practice at attic-style truss system - above conditioned space

CAD File

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

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

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Pumpkin Ridge Passive House Video #13: Completed Wall-to-Attic Air Barrier Details

Video

Video describing the wall-to-attic air barrier details of a passive house.

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

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

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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Dropped Ceiling/Soffit Below Unconditioned Attic

Guide

Guide describing how to insulate and air-seal dropped ceilings and soffits to prevent air leakage.

DOE ZERH HIA 2017 Case Study: Thrive Home Builders, Courtyard Rows, Lone Tree, CO

Case Study

Case study describing a DOE Zero Energy Ready Home 2017 Housing Innovation Award winner that scored HERS 41 without PV and 8 with PV.