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Raised ceiling duct chase installation technique

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Measure Guideline: Buried and/or Encapsulated Ducts

Reference

Project discussing buried or encapsulated ducts and their pros and cons.

Design Options for Locating Ducts within Conditioned Space

Presentation

Presentation with technical training covering several possible approaches to locating ducts within the home’s air and thermal barriers, and then dig into design considerations and details for the spray foam encapsulation approach.

Wrong: Duct is hung between truss members by strapping and not buried

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Duct boots and other ceiling penetrations are air-sealed using spray foam

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Right: Ductwork is installed in direct contact with lower truss cords. In this picture the main trunk is laying on the truss cords and branch ducts are temporarily held with strapping across truss cords. Ducts are well sealed with mastic

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Install wood framing cross pieces in the attic rafter bays on each side of the duct chase

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Unvented Attic Insulation

Guide

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

Moisture Performance of Unvented Attics with Vapor Diffusion Ports and Buried Ducts in Hot, Humid Climates

Reference

Report on the use of vapor diffusion ports to reduce moisture issues with buried ductwork in unvented attics in hot-humid climates.

Install wood framing cross pieces in the attic rafter bays on each side of the duct chase

Image

Wrong: Ducts are not laid across the lower truss cords or ceiling, but are hung from the rafters by straps. As a result, ductwork is not buried

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Second layer of rigid insulation is adhered with foam

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

Presentation

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

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.

Attic Air Sealing, Insulating, and Ventilating for Ice Dam Prevention

Information Guide

Information guide describing proper attic air-sealing, insulation, and ventilation to combat ice dam formation on roofs in cold climate zones.

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

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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.

Form an insulation dam of heat-resistant insulation with at least 3 inches of clearance 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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Air Sealing, Insulating, and Venting Attics and Roofs to Reduce Heat Gain

Information Guide

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.

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.

Attic Eave Minimum Insulation

Guide

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

Unvented Conditioned Attic with Spray Foam Insulation Below Roof Deck

Guide

Guide describing a method for insulating an unvented attic by spraying foam insulation along the underside of the roof deck.

Right - The energy recovery ventilator ducts supply filtered outside air to multiple locations in the home and continuously exhaust stale air to provide clean, balanced ventilation.

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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

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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.

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

Image

Raised ceiling duct chase installation technique

Measure Guideline: Buried and/or Encapsulated Ducts

Design Options for Locating Ducts within Conditioned Space

Wrong: Duct is hung between truss members by strapping and not buried

Duct boots and other ceiling penetrations are air-sealed using spray foam

Right: Ductwork is installed in direct contact with lower truss cords. In this picture the main trunk is laying on the truss cords and branch ducts are temporarily held with strapping across truss cords. Ducts are well sealed with mastic

Install wood framing cross pieces in the attic rafter bays on each side of the duct chase

Unvented Attic Insulation

Moisture Performance of Unvented Attics with Vapor Diffusion Ports and Buried Ducts in Hot, Humid Climates

Install wood framing cross pieces in the attic rafter bays on each side of the duct chase

Wrong: Ducts are not laid across the lower truss cords or ceiling, but are hung from the rafters by straps. As a result, ductwork is not buried

Second layer of rigid insulation is adhered with foam

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

Blown Insulation for Existing Vented Attic

Attic Air Sealing, Insulating, and Ventilating for Ice Dam Prevention

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

Batt Insulation for Existing Vented Attics

Form an insulation dam of heat-resistant insulation with at least 3 inches of clearance around a flue pipe in the attic after air sealing around the pipe with sheet metal and fire-rated caulk or canned foam

Air Sealing, Insulating, and Venting Attics and Roofs to Reduce Heat Gain

Spray Foam Insulation Applied to Existing Attic Floor

Attic Eave Minimum Insulation

Unvented Conditioned Attic with Spray Foam Insulation Below Roof Deck

Right - The energy recovery ventilator ducts supply filtered outside air to multiple locations in the home and continuously exhaust stale air to provide clean, balanced ventilation.

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

Below Deck Spray Foam Insulation for Existing Roofs

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

Air Sealing and Insulating Ceilings in Vented Attics

Water Managed Roof – Re-roofing and Adding Insulation Over a Sloped Roof

Ceiling gypsum board has been installed

Air Sealing Bathroom and Kitchen Exhaust Fans