BASC Search | Building America Solution Center

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

Image

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

Image

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

Image

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.

Image

No insulation installed in cavity and not air sealed

Image

Sealed and Insulated Flex Ducts

Guide

Guide describing how to air seal and insulate flex ducts.

HVAC Ducts Shall Not Be Run within Exterior Walls

Guide

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

Sealed and Insulated Metal Ducts

Guide

Guide describing how to air seal and insulate metal ducts.

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

Image

Monitoring of Unvented Roofs with Fibrous Insulation, Diffusion Vents, and Interior Vapor Control in a Cold Climate

Reference

Report detailing a three-winter study on unvented roof assemblies in a cold climate, assessing insulation material, ridge diffusion vent presence, vapor control membranes, relative humidity, and interstitial airflow. Results indicate that utilizing air-permeable fibrous fill insulations in unvented...

Monitoring of Unvented Roofs with Fibrous Insulation, Diffusion Vents, and Interior Vapor Control in a Cold Climate

Reference

Report detailing a three-winter study on unvented roof assemblies in a cold climate, assessing insulation material, ridge diffusion vent presence, vapor control membranes, relative humidity, and interstitial airflow; results indicate that utilizing air-permeable fibrous fill insulations in unvented...

Sealed and Insulated Fiber Board Ducts

Guide

Guide describing how to air seal and insulate fiber board ducts.

Cut-away view showing unsealed gaps around a heating duct that goes through a wall

Image

Builders Challenge High Performance Builder Spotlight: David Weekley Homes, Houston, Texas

Case Study

Case study describing new home construction in the hot-humid climate, optimizing thermal enclosure, HVAC, water heating and lighting measures.

New Whole-House Solutions Case Study: Insight Homes: Deep Creek, Seaford, Delaware

Case Study

Case study describing a home builder that has refined its home designs to achieve HERS scores of 49 to 56 on 40 to 70 homes per year.

Building Code Training - Residential Thermal Envelope - Air Sealing

Presentation

Presentation describing the Georgia State Minimum Standard Energy Code air barrier requirements, envelope concepts including air flow and thermal properties, and common missed insulation and air-sealing opportunities.

Form a sheet metal shield around the flue pipe

Image

Form sheet metal shield around pipe keeping 3-inch clearance

Image

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

Image

Ducts in Dropped Ceilings

Guide

Guide describing method for installing ducts in a duct chase in a dropped ceiling.

Small Commercial Building Fact Sheet - Building Envelope

Reference

Fact sheet describing building envelope performance measures applicable to residential and small commercial construction.

Existing Whole-House Solutions Case Study: Deep Energy Retrofit in the Pacific Northwest

Case Study

Case study describing a whole-house, deep energy retrofit project in the marine climate.

Ducts in Interstitial Floor Framing

Guide

Guide for designing and installing interior ducts in an interstitial floor cavity in new and existing homes.

No Ducts or Air Handlers Located in Garage

Guide

Guide describing how to design HVAC systems to be located within the conditioned space of the home, either in a utility closet or in an attic, basement, or crawl space.

Building America Best Practices Case Study Whole-House Solutions for New Homes - Artistic Homes, Albuquerque, NM

Reference

Case study about Artistic Homes of Albuquerque, New Mexico, the first home builder in the United States to offer true net zero energy construction to the average home buyer on every home it builds.

Ducts in Raised Ceiling Sections

Guide

Guide describing method for designing and installing ducts in a raised ceiling chase.

New Whole-House Solutions Case Study: Nelson Construction: Hamilton Way, Farmington, CT

Case Study

Case study describing the design and testing of 10 high-performance homes in Farmington, Connecticut.

Compact Air Distribution

Guide

Guide describing design and installation of compact duct systems for central heating and cooling systems.

Air Sealing Duct and Flue Shafts

Guide

Guide describing how to air-seal duct and flue shafts.

New Whole-House Solutions Case Study: Tom Walsh & Co., New Columbia, Portland, OR

Case Study

Case study describing a new construction building project of 20 homes that earned HERS scores that represent greater than 50% energy savings in heating and cooling over the 2004 IECC.