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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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There are three potential locations for an attic radiant barrier – adhered to the underside of the roof decking, hanging from the rafters, or on the ceiling insulation

There are three potential locations for an attic radiant barrier – adhered to the underside of the roof decking, hanging from the rafters, or on the ceiling insulation

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The spray foam-insulated attic provides a temperate place for the ERV ducts, which provide filtered fresh air to every room in the house.

The spray foam-insulated attic provides a temperate place for the ERV ducts, which provide filtered fresh air to every room in the house.

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Wrong - Batt insulation does not provide complete coverage across the attic floor so ceiling joists are exposed resulting in thermal bridging.

Wrong - Batt insulation does not provide complete coverage across the attic floor so ceiling joists are exposed resulting in thermal bridging.

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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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Right – Sheathing extends to rafters adding strength to soffit, baffles keep attic insulation from vent to maintain air flow

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Sloped roof with cavity spray foam insulation sprayed on underside of roof deck and covered with sprayed-on thermal or ignition barrier coating.

Sloped roof with cavity spray foam insulation sprayed on underside of roof deck and covered with sprayed-on thermal or ignition barrier coating.

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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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Spray foam insulation is applied along the underside of the roof deck to provide a conditioned and non-vented attic space for ducts and air handlers.

Spray foam insulation is applied along the underside of the roof deck to provide a conditioned and non-vented attic space for ducts and air handlers.

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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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Baffles provide an air space over the insulation to guide ventilation air from the soffit vents up along the underside of the roof deck

Baffles provide an air space over the insulation to guide ventilation air from the soffit vents up along the underside of the roof deck

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Right - A technician applies a thin layer of closed-cell foam to air-seal an unvented attic assembly before filling the ceiling joists with batt or blown insulation.

Right - A technician applies a thin layer of closed-cell foam to air-seal an unvented attic assembly before filling the ceiling joists with batt or blown insulation.

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Clean the attic floor of debris prior to installing new attic insulation. Use baffles to provide a path for ventilation air entering the attic from the soffit vents

Clean the attic floor of debris prior to installing new attic insulation. Use baffles to provide a path for ventilation air entering the attic from the soffit vents

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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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Seal the drywall to top-plate seams and the lower edge of baffles to the top plate to prevent the air coming from soffit vents from flowing under baffles into insulation.

Seal the drywall to top-plate seams and the lower edge of baffles to the top plate to prevent the air coming from soffit vents from flowing under baffles into insulation.

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This vaulted ceiling has 7 inches of closed-cell spray foam plus an R-22 unfaced mineral wool batt for a total attic insulation value of R-68.

This vaulted ceiling has 7 inches of closed-cell spray foam plus an R-22 unfaced mineral wool batt for a total attic insulation value of R-68.

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Form an insulation dam of sheet metal around a flue pipe in the attic after air sealing around the pipe with sheet metal and fire-rated caulk or canned foam

Form an insulation dam of sheet metal around a flue pipe in the attic after air sealing around the pipe with sheet metal and fire-rated caulk or canned foam

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Above the 20 inches of blown cellulose ultra-efficient attic insulation, Near Zero Maine installed a walkway in the attic to provide easy access to electric wiring.

Above the 20 inches of blown cellulose ultra-efficient attic insulation, Near Zero Maine installed a walkway in the attic to provide easy access to electric wiring.

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Underneath the roof sheathing and two exterior layers of rigid foam, the builder stapled netting to the underside of the rafters and filled the roof cavities of the unvented attic with blown-in fiberglass insulation.

Underneath the roof sheathing and two exterior layers of rigid foam, the builder stapled netting to the underside of the rafters and filled the roof cavities of the unvented attic with blown-in fiberglass insulation.

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The unvented attic is insulated along the underside of the roof deck with 7 inches (R-49) of closed-cell spray foam, providing vaulted ceilings and a conditioned knee wall space for ducting.

The unvented attic is insulated along the underside of the roof deck with 7 inches (R-49) of closed-cell spray foam, providing vaulted ceilings and a conditioned knee wall space for ducting.

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Right - This new sealed attic has 5.5 inches (R-20) of spray foam insulation along the underside of the roof deck providing a conditioned attic space for the heating and cooling ducts.

Right - This new sealed attic has 5.5 inches (R-20) of spray foam insulation along the underside of the roof deck providing a conditioned attic space for the heating and cooling ducts.

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Retrofit an existing roof by installing rigid foam, new moisture and air control layers, new sheathing, and new cladding plus cavity insulation in the roof rafters to create an unvented attic

Retrofit an existing roof by installing rigid foam, new moisture and air control layers, new sheathing, and new cladding plus cavity insulation in the roof rafters to create an unvented attic

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Wrong: Closed-cell spray foam roof insulation was not thick enough to meet IRC levels so the foam surface is colder than the dew point of the interior air and condensation formed on surface of the foam

Wrong: Closed-cell spray foam roof insulation was not thick enough to meet IRC levels so the foam surface is colder than the dew point of the interior air and condensation formed on surface of the foam

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A floor cavity between the first and second floor can provide a conditioned space for HVAC ducts if the rim joists are insulated and air sealed, if sufficient space is available, and if open-web floor joists are used

A floor cavity between the first and second floor can provide a conditioned space for HVAC ducts if the rim joists are insulated and air sealed, if sufficient space is available, and if open-web floor joists are used

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A simple vented attic with good air-sealing of the drywall ceiling air barrier, air flow from soffit vents to ridge vents protected by ventilation baffles, and lots of insulation covering the attic floor is unlikely to encourage ice dams.

A simple vented attic with good air-sealing of the drywall ceiling air barrier, air flow from soffit vents to ridge vents protected by ventilation baffles, and lots of insulation covering the attic floor is unlikely to encourage ice dams.

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ICF walls and an attic sealed and insulated to R-63 on the underside of the roof deck with 10 inches of open‐cell spray foam plus 2.7 inches of closed‐cell spray foam provide a complete thermal break around this home.

ICF walls and an attic sealed and insulated to R-63 on the underside of the roof deck with 10 inches of open‐cell spray foam plus 2.7 inches of closed‐cell spray foam provide a complete thermal break around this home.

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This attic is insulated to R-64 with a hybrid application of 11 inches of open-cell spray foam (R-4.45/in) plus 2 inches of closed-cell spray foam (R-7.4/in) that completely fills the roof rafter cavities and encases the rafters.

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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.

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