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Sealed and Insulated Metal Ducts

Guide

Guide describing how to air seal and insulate metal ducts.

Sealed and Insulated Flex Ducts

Guide

Guide describing how to air seal and insulate flex ducts.

Ducts Buried in Attic Insulation

Guide

Guide describing the practice of burying HVAC ducts in loose-fill insulation on the attic floor.

When it comes to refrigerant line insulation, the 80-20 rule does not apply! Insulate the whole pipe.

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Ducts Buried in Attic Insulation and Encapsulated

Guide

Guide describing approaches to burying and encapsulating ducts in unconditioned attics to increase the overall R-value of duct insulation.

Remove and replace the old insulation on the refrigerant line of your air conditioner’s compressor unit if the insulation becomes cracked or damaged.

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Pull the insulation and outer liner of the flex duct over the collar to come in full contact with the liner and insulation of the trunk line or fitting and tape in place

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This refrigerant line was correctly insulated and wrapped with a weather-resistant covering but the tape covering is losing its adhesion due to exposure; pipe insulation should be checked annually for wear.

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Right – An insulated space is provided in the home’s attic to house the HVAC equipment.

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Seal all joints and seams in the metal ductwork with mastic before installing insulation

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This refrigerant line pipe insulation has been significantly degraded by exposure to the weather and needs to be replaced.

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A nylon draw band and tensioning tool are used to secure the inner coil of the pre-insulated flexible duct

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A nylon draw band and tensioning tool are used to secure the inner liner of the pre-insulated flexible duct

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When wrapping metal ducts with insulation allow two inches of overlap and staple along the seam with outward clinching staples

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

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Install new insulation on the refrigerant line of your air conditioner’s compressor unit to protect the pipe and improve your cooling system’s efficiency.

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Flowhood is sealed against the irregular surface using pipe insulation along the edge of the hood to complete an airtight seal around the terminal.

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This pipe insulation for air conditioner and heat pump refrigerant lines comes with an integrated UV-resistant vapor barrier layer for protection against the sun and harsh weather.

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Right – The HVAC unit installed in the insulated attic uses a heat pump to provide heating and cooling while also providing dehumidification and fresh air ventilation.

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The inside refrigerant line leading from the air conditioner or heat pump to the wall should be covered with pipe insulation and a vapor barrier to reduce condensation potential and improve system efficiency.

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The new pipe insulation on these heat pump refrigerant lines is wrapped in UV-resistant tape starting from the bottom and working up; the tape layers are shingled to prevent water entry.

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To attach the flex duct to a main trunk duct or any other connection, the flex duct is pulled over the connecting collar at least 2 inches past the raised bead, then the insulation is pulled back

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The mechanical room in the insulated basement houses the water heating equipment, including the storage tank for the solar thermal system and the wall-hung boiler as well as the air handler for the hydro coil and high-efficiency (16 SEER) air conditioner.

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Right - The precast insulated concrete walls of the basement provide a conditioned space for the high-efficiency (18 SEER, 9.5 HSPF) air-source heat pump, with its variable-speed fan, five-stage compressor, and MERV 11 filter.

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Encapsulated Ducts

Video

Video describing air sealing and insulation for encapsulated ducts.

Compact Buried Ducts in a Hot-Humid Climate House

Reference

Report on heating and cooling air-distribution ducts that are insulated, installed close to the ceiling in a vented attic and covered with attic insulation to minimize energy loss.

DOE ZERH HIA 2017 Case Study: United Way of Long Island, United Veterans Beacon House, Huntington Station, NY

Case Study

Case study showing project and performance data and energy-efficiency measures for a DOE 2017 Housing Innovation Award winning home that was certified to the DOE Zero Energy Ready Home criteria.

Support at Intervals for Flex Ducts

Guide

Guide describing how to hang HVAC ducts with supporting straps or saddles to adequately support ducts so they do not sag and are not pinched or compressed.

Sufficient Cavity Space for Flex Ducts

Guide

Guide describing how and where to install ducts, to ensure enough cavity space to avoid compression of the flex ducts or duct insulation.

HVAC Ducts Shall Not Be Run within Exterior Walls

Guide

Guide describing the use of building cavities as supply or return ducts.