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Unvented Attic Insulation

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

Why Seal and Insulate?

Author(s)

ENERGY STAR

Organization(s)

ENERGY STAR

Publication Date

August, 2020

Introductory guide to air sealing the envelope of a home to reduce wasted energy and save on energy costs.

Insulating Existing Floor Overhang

Guide describing how to upgrade a wall with a floor overhang (or cantilever) on an existing home by adding insulation (rigid insulating sheathing and/or closed-cell spray foam) and air-sealing.

Air Sealed, Insulated Basements

Guide describing how to insulate a basement to improve the overall thermal performance of the building and provide more dry, usable conditioned space for home occupants and HVAC equipment.

Insulating Existing Floors over Garage

Guide with information about how to upgrade a garage ceiling when a portion of the interior of the house is located directly above the attached garage by adding insulation and air sealing.

Batt Insulation for Existing Vented Attics

Guide describing how to increase insulation in existing homes by installing batt insulation on the ceiling plane of a vented attic.

Blown Insulation for Existing Vented Attic

Guide describing how to insulate a vented attic in an existing home using blown insulation added to the attic floor.

Stucco Over Rigid Foam Insulation

Guide describing how to install stucco over rigid foam insulation in new and existing homes.

Air seal and insulate light tube

Publication Date

Sat, 09/22/2012 - 12:00

Blown Insulation for Cavities of Existing Exterior Walls

Guide describing blown insulation into exterior wall cavities of existing homes with minimal disruption to occupants.

The attic kneewall and the open floor cavities under kneewall are both sealed and insulated in one step with spray foam insulation

Publication Date

Tue, 12/01/2009 - 12:00

Insulated whole-house fan cover

Publication Date

Mon, 03/01/1999 - 12:00

Rigid Foam Insulation for Existing Exterior Walls

Guide describing how to apply an air control layer directly over existing wall sheathing and cover with two layers of insulating sheathing held in place by vertical furring strips.

Certified Insulated Siding: Quality, Comfort and Energy Performance

Author(s)

Dobson,

Brignati

Organization(s)

Vinyl Siding Institute,

Newport Ventures

This presentation will help you define insulated siding, understand R-value testing of insulated siding, describe proper installation of insulated siding, comply with energy codes and understand building energy performance program and software recognition.

Spray Foam Insulation Applied to Existing Attic Floor

Guide describing how to apply spray foam insulation to ceilings in existing homes.

Wrong – Fibrous insulation does not air seal

Publication Date

Fri, 10/28/2011 - 12:00

Air Sealing Structural Insulated Panel (SIP) Seams

Guide describing how to correctly seal structural insulated panel (SIP) seams.

Right – The rim joists above the pre-insulated basement walls are sealed and insulated with spray foam to prevent air leakage at this juncture in the building envelope.

Publication Date

Thu, 09/30/2021 - 12:00

1 inch exterior insulation sheathing as attic eave baffle and vent

DWG

PDF

Air seal and insulate drawer and closet boxes in attic kneewalls

Reference

Retrofit Techniques and Technologies: Air Sealing, Volume 10

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Williamson Jennifer,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

Report identifying the steps to take, with the help of a qualified home performance contractor, to seal unwanted air leaks while ensuring healthy levels of ventilation and avoiding sources of indoor air pollution.

Publication Date

Mon, 04/12/2010 - 12:00

Unvented Conditioned Attic with Spray Foam Insulation Below Roof Deck

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

Wrong – Whole house fan installed without an insulated cover

Publication Date

Fri, 10/28/2011 - 12:00

Wrong – Drop down stairs do not have insulation cover installed

Publication Date

Fri, 10/28/2011 - 12:00

Wrong – Attic access panel does not have an insulation cover installed

Publication Date

Fri, 10/28/2011 - 12:00

Wrong – Fibrous insulation is not an air barrier and cannot be used for sealing holes.

Publication Date

Fri, 10/28/2011 - 12:00

Wrong – Fibrous insulation is not an air barrier and cannot be used for sealing holes.

Publication Date

Fri, 10/28/2011 - 12:00

Wrong – No blocking installed to prevent attic insulation from falling into stairs and opening

Publication Date

Fri, 10/28/2011 - 12:00

Wrong – Fibrous insulation is not an air barrier and cannot be used to air-seal openings.

Publication Date

Fri, 10/28/2011 - 12:00

Right – Blocking has been installed around the perimeter of this attic access to prevent insulation falling into the house

Publication Date

Fri, 10/28/2011 - 12:00

Install an ENERGY STAR labeled insulated door with an automatic closer. Weather strip the door frame

Reference

Retrofit Techniques and Technologies: Air Sealing, Volume 10

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Williamson Jennifer,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

Report identifying the steps to take, with the help of a qualified home performance contractor, to seal unwanted air leaks while ensuring healthy levels of ventilation and avoiding sources of indoor air pollution.

Publication Date

Mon, 04/12/2010 - 12:00

Building America Existing Home Case Study: Insulated Siding Retrofit in a Cold Climate, New Paltz, New York

Author(s)

Florida Solar Energy Center

Organization(s)

BA-PIRC,

FSEC

Publication Date

April, 2015

Case study describing the application of insulated siding on an existing home.

Right – This attic knee wall and the floor joist cavity openings beneath it are being sealed and insulated with spray foam.

Publication Date

Tue, 12/01/2009 - 12:00

Right – Attic access hatch has been properly insulated by attaching a fiberglass batt, gasketed, and opening has blocking

Publication Date

Sat, 10/01/2011 - 12:00

All seams between structural insulated panels (SIPs) foamed and/or taped per manufacturer's instructions

Publication Date

Fri, 10/28/2011 - 12:00

Right-- IR photo shows how effectively spray foam insulated/air sealed attic kneewall and the floor cavities under kneewall

Publication Date

Tue, 12/01/2009 - 12:00

Fill in the hole left by the missing top plate with a rigid air blocking material or rolled batt insulation that is spray foamed in place

Publication Date

Fri, 06/01/2012 - 12:00

Right - This ceiling-mounted mini whole-house fan has built-in insulated covers to reduce heat loss when the fan is not in use

Publication Date

Sat, 10/01/2011 - 12:00

Right - New flashing has been installed to complete the air and water control layers at the window openings of this wall retrofit that includes insulating the wall cavities with spray foam

Skylight Shaft Walls

Guide describing insulation techniques for skylight shaft walls.

Vented versus Unvented Attic

Guide describing options for designing and locating the thermal boundary at either the attic floor or along the roof line in new and existing homes.

Wind Washing

Guide describing wind washing and how to prevent it.

Dropped Ceiling/Soffit Below Unconditioned Attic

Guide describing how to insulate and air-seal dropped ceilings and soffits to prevent air leakage.

Vinyl Siding with Integrated Rigid Foam for Existing Walls

Guide describing the design and installation considerations for recladding of above grade walls using insulated vinyl siding.

Air Sealing Attic Access Panels/Doors/Stairs

Guide describing how to air-seal attic access panels, doors, and stairs to provide a continuous air barrier at the ceiling.

Advanced Framing vs Traditional Framing

Publication Date

December, 2012

Author(s)

Risinger

Organization(s)

Build with Matt Risinger

Video describing traditional 2x4 16 inch on center framing versus advanced framing with 2x6 stud walls at 24 inch on center, insulated corners and headers, wall stud-ceiling joist alignment, etc. providing a strong wall with more room for insulation.

Install Top Plates or Blocking at the Top of Walls Adjoining Unconditioned Spaces

Guide describing how to correctly air-seal a wall with missing top plates or open wall cavities.

Walls Behind Fireplaces

This guide describes how to install a rigid air barrier to walls behind fireplaces.

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

Author(s)

Pacific Northwest National Laboratory,

U.S. Department of Energy

Organization(s)

PNNL,

DOE

Publication Date

September, 2017

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.

Air Sealing Drywall to Top Plate

Guide describing ways to seal drywall to the top plate of an exterior wall to air-seal the wall cavity.

Technology Solutions Case Study: Stand-Off Furring in Deep Energy Retrofits

Author(s)

IBACOS

Organization(s)

IBACOS

Publication Date

May, 2014

Case study describing a stand-off furring strategy that minimizes the physical connections to each existing wall stud, uses spray foam to encapsulate existing siding materials (including lead paint), and creates a vented rain screen assembly to promote drying.

Air leaking through the home's envelope wastes a lot of energy and increases energy costs.

Publication Date

Wed, 01/01/2020 - 12:00

Air Sealing Duct and Flue Shafts

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

Air-seal the attic kneewall door opening with weatherstripping.

Publication Date

Thu, 01/01/2009 - 12:00

Technology Solutions Case Study: Complete and Fully Aligned Air Barrier

Author(s)

Pacific Northwest National Laboratory

Organization(s)

PNNL

Publication Date

August, 2012

Case study describing the elimination of excessive humidity in the attic of a multi-floor, single-family home that was causing condensation and water damage along the roof and eaves.

Air Sealing Light Tubes

Guide describing how to air-seal around light tubes.

Home Performance Assessment

Information guide describing how to apply a whole-house approach to home improvement with energy efficiency upgrades, improved indoor air quality, and increased comfort.

Mastic Home Exteriors Installation Guide

Author(s)

Ply Gem Siding Group

Organization(s)

Ply Gem Siding Group

Publication Date

April, 2015

Siding installation guide for Ply Gem Siding Group products.

Air Sealing Recessed Light Fixtures Below Unconditioned Space

Guide describing how to air-seal around recessed light fixtures below unconditioned space.

DOE ZERH HIA 2017 Case Study: Thrive Home Builders, Courtyard Rows, Lone Tree, CO

Author(s)

Pacific Northwest National Laboratory,

U.S. Department of Energy

Organization(s)

PNNL,

DOE

Publication Date

September, 2017

Case study describing a DOE Zero Energy Ready Home 2017 Housing Innovation Award winner that scored HERS 41 without PV and 8 with PV.

Air Sealing Sill Plates

Guide describing how to air-seal sill plates in single-family homes and multifamily buildings.

Air Sealing Bathroom and Kitchen Exhaust Fans

Guide describing how to air-seal bathroom and kitchen exhaust fans.

Aerosol Sealing Building Enclosures, Single and Multifamily Dwellings - Code Compliance Brief

Publication Date

January, 2020

The intent of this brief is to provide code-related information for aerosol sealing building enclosures to achieve durable air tightness levels that will be accepted as being in compliance with the code.

Technology Solutions Case Study: Preventing Thermal Bypass

Author(s)

Pacific Northwest National Laboratory

Organization(s)

PNNL

Publication Date

October, 2012

Case study describing techniques used to prevent thermal bypass in new homes.

Air Sealing Attached Garage

Guide describing ways to air-seal an attached garage in new and existing homes.

Form a sheet metal shield around the flue pipe

Form sheet metal shield around pipe keeping 3-inch clearance

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

Energy Efficient Log Cabin Construction Workshop

Publication Date

May, 2013

Organization(s)

Cold Climate Housing Research Center,

CCHRC

Video describing log cabin wall construction and insulation in Alaska.

New Whole-House Solutions Case Study: Pine Mountain Builders, Pine Mountain, Georgia

Author(s)

Pacific Northwest National Laboratory

Organization(s)

PNNL

Publication Date

January, 2013

Case study describing a builder in Georgia that designs energy-efficient homes for a green community, yielding homes with HERS scores as lowas 59 and electric bills as low as $50 a month.

The thermal boundary for a gable roof can be located at either a) the flat ceiling with a vented attic or b) the roof line for an unvented attic

A low-sloped shed roof with the thermal boundary located at either a) the flat ceiling with a vented attic or b) the roof line for an unvented attic

A 1- and ½-story home with a room located in the attic and the thermal boundary located at either a) the walls and ceiling of the attic room with small vented attic spaces or b) the roof line for an unvented attic

This kneewall has no top plate and the resulting gap provides a wide-open pathway for air and vapor to travel between the living space and the attic

gutters and good drainage

Publication Date

October, 2011

Author(s)

Cold Climate Housing Research Center

Organization(s)

CCHRC

Video from Cold Climate Housing Research Center explaining how to correctly 'fur' and outside wall for maximum insulation protection.

Wrong – There is no weather stripping or gasket around the attic stair hatch

Publication Date

Fri, 10/28/2011 - 12:00

Small Commercial Building Fact Sheet - Building Envelope

Author(s)

Southface Energy Institute

Organization(s)

SEI

Publication Date

November, 2016

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

Air seal attic access panels and drop-down stairs to minimize air leakage.

Publication Date

Fri, 10/28/2011 - 12:00

Air Sealing Plumbing and Piping

Guide describing how to air-seal around plumbing and piping penetrations through walls, ceilings, and floors.

Right – Attic access door has foam and rubber weatherstripping installed that remains in contact when closed.

Publication Date

Fri, 10/28/2011 - 12:00

Opportunities for Energy Conservation and Improved Comfort From Wind Washing Retrofits in Two-Story Homes - Part II

Author(s)

Withers Charles R,

Cummings James B

Organization(s)

Florida Solar Energy Center,

FSEC

Publication Date

September, 2010

Report presenting the results of a study evaluating retrofit solutions for addressing the effects of wind washing on homes.

Whole-House Fans

Guide describing the types of whole-house fans, installation details to reduce energy loss, and how to operate them for comfort and energy savings based on climate zone.

Air seal the attic access panel with weather stripping

Reference

Retrofit Techniques and Technologies: Air Sealing, Volume 10

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Williamson Jennifer,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

Report identifying the steps to take, with the help of a qualified home performance contractor, to seal unwanted air leaks while ensuring healthy levels of ventilation and avoiding sources of indoor air pollution.

Publication Date

Mon, 04/12/2010 - 12:00

Air seal the attic access pull-down stairs opening with weather stripping

Reference

Retrofit Techniques and Technologies: Air Sealing, Volume 10

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Williamson Jennifer,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

Report identifying the steps to take, with the help of a qualified home performance contractor, to seal unwanted air leaks while ensuring healthy levels of ventilation and avoiding sources of indoor air pollution.

Publication Date

Mon, 04/12/2010 - 12:00

Moisture Control for Residential Buildings

Author(s)

Lstiburek Joseph W

Organization(s)

Building Science Corporation,

BSC,

U.S. Department of Energy,

DOE

Publication Date

September, 2020

Report providing extensive guidance on controlling moisture in building envelopes through proper selection and installation on air, water, thermal, and vapor barriers.

Air Sealing Doors Adjacent to Unconditioned Space

Guide describing how to air-seal doors that are next to unconditioned spaces.

Mass Save Deep Energy Retrofit Builder Guide, GM-1302

Author(s)

Neuhauser Ken,

Gates Cathy,

Pettit Betsy

Organization(s)

Building Science Corporation,

BSC

Publication Date

July, 2013

Guidebook providing useful examples of high performance retrofit techniques for the building enclosure of wood frame residential construction in a cold and somewhat wet climate.

DOE ZERH HIA 2014 Case Study: One Sky Homes, Cottle Zero Net Energy Home, San Jose, CA

Author(s)

Pacific Northwest National Laboratory,

U.S. Department of Energy

Organization(s)

PNNL,

DOE

Publication Date

September, 2014

Case study describing a DOE Zero Energy Ready Home 2014 Housing Innovation Award winner that scored HERS 69 without PV and -1 with PV.

Air Sealing Modular Home Marriage Joints

Guide describing how to air-seal modular home marriage joints.

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

Author(s)

Pacific Northwest National Laboratory

Organization(s)

PNNL

Publication Date

February, 2013

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.

New Whole-House Solutions Case Study: Lancaster County Career and Technology Center Green Home 3 - Mount Joy, Pennsylvania

Author(s)

Home Innovation Research Labs

Organization(s)

HIRL

Publication Date

December, 2014

Case study describing the Green Home 3 project, which achieved a 44% whole-house energy savings over the Building America New Construction B10 Benchmark, DOE Zero Energy Ready Home certification, and National Green Building Standard Gold-level certification.

Air Sealing Electrical Wiring

Guide describing how to air-seal electrical wiring throughout a home.

New Whole-House Solutions Case Study: Schneider Homes, Inc., Village at Miller Creek, Burien, WA

Author(s)

Pacific Northwest National Laboratory

Organization(s)

PNNL

Publication Date

February, 2013

Case study describing new home construction in the marine climate that achieved 50% savings over the 2004 IECC.

DOE ZERH HIA 2017 Case Study: Thrive Home Builders, Lowry Plan, Denver, CO

Author(s)

Pacific Northwest National Laboratory,

U.S. Department of Energy

Organization(s)

PNNL,

DOE

Publication Date

September, 2017

Case study describing a DOE Zero Energy Ready Home 2017 Housing Innovation Award winner that scored HERS 38 without PV and 4 with PV.