BASC Search | Building America Solution Center

Calculating Attic Passive Ventilation

Information guide describing how to calculate attic passive ventilation with example calculations.

Understanding Attic Ventilation, BSD-102

Author(s)

Lstiburek Joseph W

Organization(s)

Building Science Corporation,

BSC

Publication Date

October, 2006

BSD-102 report providing guidance about whether to construct a vented or unvented attic based on hygro-thermal zone.

This HRV, installed in a conditioned attic, provides balanced ventilation to the whole home

Reference

Measure Guideline: Selecting Ventilation Systems for Existing Homes

Author(s)

Aldrich Robb

Organization(s)

Consortium for Advanced Residential Buildings,

CARB,

Steven Winter Associates,

SWA,

U.S. Department of Energy,

DOE

This document addresses adding—or improving—mechanical ventilation systems to existing homes. The purpose of ventilation is to remove contaminants from homes either directly or by dilution. This report discusses where, when, and how much ventilation is appropriate in a home, including some discussion of relevant codes and standards.

Publication Date

Sat, 02/01/2014 - 12:00

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.

Unvented Attic Insulation

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

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.

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.

Attic Radiant Barriers

Guide describing application of a radiant barrier layer in the attic to block radiant heat transfer between hot surfaces and heat-absorbing surfaces.

Attic Eave Minimum Insulation

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

Whole House Ventilation Strategies for Existing Homes

Guide describing how to select and install whole-house ventilation systems for existing homes.

Spray Foam Insulation Applied to Existing Attic Floor

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

Air Sealing and Insulating Ceilings in Vented Attics

Guide describing how to air-seal and insulate a ceiling where the insulation is installed on top of the ceiling (on the attic floor) in a vented attic.

Pre-Retrofit Assessment of Attics, Ceilings, and Roofs

Information guide describing things to consider in the attic, ceiling, or roof before attempting retrofits of items including HVAC, wiring, or structural systems.

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

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.

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

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.

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

Dropped Ceiling/Soffit Below Unconditioned Attic

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

Baffles provide an air space over the insulation to guide ventilation air from the soffit vents up along the underside of the roof deck

Publication Date

Thu, 06/28/2012 - 12:00

Below Deck Spray Foam Insulation for Existing Roofs

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.

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.

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.

Wind Washing

Guide describing wind washing and how to prevent it.

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.

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.

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 Sealing Bathroom and Kitchen Exhaust Fans

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

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.

Ducts in Raised Ceiling Sections

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

Building Science Introduction - Air Flow

Information guide providing background information about air flow in residential buildings.

Air Sealing Modular Home Marriage Joints

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

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.

Low-E Exterior Storm Windows

Guide describing how to install low-e exterior storm windows.

Rooms Containing Fuel-Burning Appliances - Code Compliance Brief

An entirely new section in the 2015 IECC/IRC regarding fuel-burning appliances basically requires the appliance to be isolated from the building thermal envelope, located either outside or within a separate room if the fuel-burning appliance is supplied by open combustion air ducts. This brief provides an overview of the requirements and further details of approving the actual "room".