Moisture permeability measurements under reduced barometric pressures

G.H. Galbraith, D.J. Kelly, R.C. McLean

Research output: Contribution to journalArticle

Abstract

The successful application of modern hygrothermal simulation models to building envelopes requires accurate values of moisture permeability. Unfortunately, the generation of reliable data is sometimes not possible using the currently-applied gravimetric test methods, because of the extremely long test periods which can be involved. In addition, these test methods are incapable of separating the total mass flow into its vapour and liquid components, the individual transfer coefficients which are required for the complete description of the moisture transmission process. This paper introduces a new approach to permeability measurement, which has been developed to overcome these deficiencies. It involves testing under reduced barometric pressures, which allows a rapid evaluation of permeability, together with the identification of the separate vapour and liquid fluxes. The new approach is validated through the presentation of experimental results for five building materials, which are compared with benchmark data on the same materials obtained from standard tests.
Original languageEnglish
Pages (from-to)311-317
Number of pages6
JournalMaterials and Structures
Volume37
Issue number269
DOIs
Publication statusPublished - 2004

Fingerprint

Moisture
Vapors
Liquids
Fluxes
Testing

Keywords

  • materials engineering
  • moisture
  • hygrothermal simulation
  • humidity
  • building design

Cite this

Galbraith, G.H. ; Kelly, D.J. ; McLean, R.C. / Moisture permeability measurements under reduced barometric pressures. In: Materials and Structures. 2004 ; Vol. 37, No. 269. pp. 311-317.
@article{4d96061e982844638b589c03e1a34b9c,
title = "Moisture permeability measurements under reduced barometric pressures",
abstract = "The successful application of modern hygrothermal simulation models to building envelopes requires accurate values of moisture permeability. Unfortunately, the generation of reliable data is sometimes not possible using the currently-applied gravimetric test methods, because of the extremely long test periods which can be involved. In addition, these test methods are incapable of separating the total mass flow into its vapour and liquid components, the individual transfer coefficients which are required for the complete description of the moisture transmission process. This paper introduces a new approach to permeability measurement, which has been developed to overcome these deficiencies. It involves testing under reduced barometric pressures, which allows a rapid evaluation of permeability, together with the identification of the separate vapour and liquid fluxes. The new approach is validated through the presentation of experimental results for five building materials, which are compared with benchmark data on the same materials obtained from standard tests.",
keywords = "materials engineering, moisture, hygrothermal simulation, humidity, building design",
author = "G.H. Galbraith and D.J. Kelly and R.C. McLean",
year = "2004",
doi = "10.1617/13992",
language = "English",
volume = "37",
pages = "311--317",
journal = "Materials and Structures",
issn = "1359-5997",
number = "269",

}

Moisture permeability measurements under reduced barometric pressures. / Galbraith, G.H.; Kelly, D.J.; McLean, R.C.

In: Materials and Structures, Vol. 37, No. 269, 2004, p. 311-317.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Moisture permeability measurements under reduced barometric pressures

AU - Galbraith, G.H.

AU - Kelly, D.J.

AU - McLean, R.C.

PY - 2004

Y1 - 2004

N2 - The successful application of modern hygrothermal simulation models to building envelopes requires accurate values of moisture permeability. Unfortunately, the generation of reliable data is sometimes not possible using the currently-applied gravimetric test methods, because of the extremely long test periods which can be involved. In addition, these test methods are incapable of separating the total mass flow into its vapour and liquid components, the individual transfer coefficients which are required for the complete description of the moisture transmission process. This paper introduces a new approach to permeability measurement, which has been developed to overcome these deficiencies. It involves testing under reduced barometric pressures, which allows a rapid evaluation of permeability, together with the identification of the separate vapour and liquid fluxes. The new approach is validated through the presentation of experimental results for five building materials, which are compared with benchmark data on the same materials obtained from standard tests.

AB - The successful application of modern hygrothermal simulation models to building envelopes requires accurate values of moisture permeability. Unfortunately, the generation of reliable data is sometimes not possible using the currently-applied gravimetric test methods, because of the extremely long test periods which can be involved. In addition, these test methods are incapable of separating the total mass flow into its vapour and liquid components, the individual transfer coefficients which are required for the complete description of the moisture transmission process. This paper introduces a new approach to permeability measurement, which has been developed to overcome these deficiencies. It involves testing under reduced barometric pressures, which allows a rapid evaluation of permeability, together with the identification of the separate vapour and liquid fluxes. The new approach is validated through the presentation of experimental results for five building materials, which are compared with benchmark data on the same materials obtained from standard tests.

KW - materials engineering

KW - moisture

KW - hygrothermal simulation

KW - humidity

KW - building design

UR - http://dx.doi.org/10.1617/13992

U2 - 10.1617/13992

DO - 10.1617/13992

M3 - Article

VL - 37

SP - 311

EP - 317

JO - Materials and Structures

JF - Materials and Structures

SN - 1359-5997

IS - 269

ER -