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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

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

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

CAD File

Installation of Cavity Insulation, Info-501

Reference

Article explaining installing cavity insulation.

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

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

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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

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

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

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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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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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Wrong – The vinyl siding at this gable was installed over plastic foam insulation

Wrong – The vinyl siding at this gable was installed over plastic foam insulation

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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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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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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.

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.

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The missing top plate in a kneewall was covered with lumber and rigid foam insulation and then sealed with spray foam

The missing top plate in a kneewall was covered with lumber and rigid foam insulation and then sealed with spray foam

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

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

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Wrong: open wall cavity connected to this return air plenum is allowing cellulose attic insulation to be pulled into the furnace

Wrong: open wall cavity connected to this return air plenum is allowing cellulose attic insulation to be pulled into the furnace

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Right - These raised heel roof trusses provide 16 inches of space over the outer walls for full insulation coverage at the attic perimeter.

Right - These raised heel roof trusses provide 16 inches of space over the outer walls for full insulation coverage at the attic perimeter.

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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.

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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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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Walls Adjoining Porch Roof

Guide

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

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.

Attic Knee Walls

Guide

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