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No insulation installed in cavity and not air sealed

Exterior Insulation Implications on Heating and Cooling in Cold Climates

Author(s)

Herk Anastasia,

Poerschke Andrew

Organization(s)

Integrated Building and Construction Solutions,

IBACOS

Publication Date

April, 2015

The New York State Energy Research and Development Authority (NYSERDA) is interested in finding cost-effective solutions for deep energy retrofits (DERs) related to exterior wall insulation in a cold climate, with targets of 50% peak load reduction and 50% space conditioning energy savings.

Inadequate amount of insulation installed with compression, misalignment, and voids

Right – Flex ducts are properly supported with straps that don’t pinch the insulation; closed-cell spray foam will be applied to the underside of the roof deck of this hot-humid climate home to provide an insulated attic space for the HVAC ducts.

Publication Date

Thu, 09/30/2021 - 12:00

Cavity used for return is not insulated and is not air sealed, which will pull in air from outside

If HVAC duct must be installed in an exterior wall, separate it from the exterior with at least R-6 of continuous rigid insulation

HVAC ducts, cavities used as ducts, and combustion inlets and outlets may pass perpendicularly through exterior walls but shall not be run within exterior walls unless at least R-6 continuous insulation is provided on exterior side of the cavity

Support at Intervals for Flex Ducts

Guide describing how to hang ducts with supporting straps or saddles to adequately support ducts so they do not sag and are not pinched or compressed in a manner that would cause damage to the ducts, the duct insulation, or the duct air barrier covering.

Organization(s)

ARIES Collaborative

Webinar explaining advances in energy efficient design for manufactured homes.

No insulation installed in cavity and not air sealed

Exterior Insulation Implications on Heating and Cooling in Cold Climates

Inadequate amount of insulation installed with compression, misalignment, and voids

Right – Flex ducts are properly supported with straps that don’t pinch the insulation; closed-cell spray foam will be applied to the underside of the roof deck of this hot-humid climate home to provide an insulated attic space for the HVAC ducts.

Cavity used for return is not insulated and is not air sealed, which will pull in air from outside

If HVAC duct must be installed in an exterior wall, separate it from the exterior with at least R-6 of continuous rigid insulation

HVAC ducts, cavities used as ducts, and combustion inlets and outlets may pass perpendicularly through exterior walls but shall not be run within exterior walls unless at least R-6 continuous insulation is provided on exterior side of the cavity

Support at Intervals for Flex Ducts

Sufficient Cavity Space for Flex Ducts

HVAC Ducts Shall Not Be Run within Exterior Walls

Home Performance Assessment

No Excessive Coiled or Looped Flex Ducts

HVAC duct layout

No Kinks or Sharp Bends in Flex Duct Installation

No Ducts or Air Handlers Located in Garage

Advances in Manufactured Home Energy Efficient Design

Example of an HVAC installer’s balancing report form

Building Cavities Not Used as Supply or Return Ducts

Pre-Retrofit Assessment of Existing HVAC Systems

Air Conditioning

Condensing Boilers

Gas-Fired Boilers