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

Ueno, Kohta; Lstiburek, Joseph W.

doi:10.2172/1697976

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

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Abstract

This research involved construction of a conditioned test hut in a cold climate (Climate Zone 5A) with multiple side-by-side instrumented roof rafter bays. This work examined seven experimental unvented roofs and one code-compliant control hybrid ccSPF-cellulose roof over three winters and following summers. Examined variables included insulation material (fiberglass and cellulose), the presence or absence of a ridge diffusion vent (vapor-open material at the roof ridge to promote drying), the effect of various interior vapor control membranes (fixed and variable permeance), the effect of interior relative humidity, and the effect of interstitial airflow (from the interior into the cavity). This experiment was run over three winters, changing variables of interior conditions, roof configurations/materials, and the addition of intentional air leakage.

Authors:

Ueno, Kohta ^[1]; Lstiburek, Joseph W. ^[1]

Building Science Corporation, Westford, MA (United States)

Publication Date:: 2020-09-15

Research Org.:: Building Science Corporation

Sponsoring Org.:: USDOE Office of Energy Efficiency and Renewable Energy (EERE)

OSTI Identifier:: 1697976

Report Number(s):: DOE/GO-102020-5450

DOE Contract Number:: EE0007570

Resource Type:: Technical Report

Country of Publication:: United States

Language:: English

Subject:: 32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; unvented roof; cathedralized roof; unvented attic; conditioned attic; fibrous insulation; fiberglass; cellulose; diffusion vent; diffusion port; attic condensation; ridge rot

Citation Formats


                    Ueno, Kohta, and Lstiburek, Joseph W. Monitoring of Unvented Roofs with Fibrous Insulation, Diffusion Vents, and Interior Vapor Control in a Cold Climate.  United States: N. p., 2020. 
        Web.  doi:10.2172/1697976.

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                    Ueno, Kohta, & Lstiburek, Joseph W. Monitoring of Unvented Roofs with Fibrous Insulation, Diffusion Vents, and Interior Vapor Control in a Cold Climate.  United States.  https://doi.org/10.2172/1697976

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                    Ueno, Kohta, and Lstiburek, Joseph W. 2020.  
        "Monitoring of Unvented Roofs with Fibrous Insulation, Diffusion Vents, and Interior Vapor Control in a Cold Climate".  United States.  https://doi.org/10.2172/1697976.  https://www.osti.gov/servlets/purl/1697976.

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@article{osti_1697976,

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

  author       = {Ueno, Kohta and Lstiburek, Joseph W.},

  abstractNote = {This research involved construction of a conditioned test hut in a cold climate (Climate Zone 5A) with multiple side-by-side instrumented roof rafter bays. This work examined seven experimental unvented roofs and one code-compliant control hybrid ccSPF-cellulose roof over three winters and following summers. Examined variables included insulation material (fiberglass and cellulose), the presence or absence of a ridge diffusion vent (vapor-open material at the roof ridge to promote drying), the effect of various interior vapor control membranes (fixed and variable permeance), the effect of interior relative humidity, and the effect of interstitial airflow (from the interior into the cavity). This experiment was run over three winters, changing variables of interior conditions, roof configurations/materials, and the addition of intentional air leakage.},

  doi          = {10.2172/1697976},

  url          = {https://www.osti.gov/biblio/1697976},
  journal      = {},
number       = ,

  volume       = ,

  place        = {United States},

  year         = {2020},

  month        = {9}

}

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