Moisture Control in Buildings: The Key Factor in Mold Prevention 2nd Edition Heinz R Trechsel Mark T Bomberg Editors Moisture Control in Buildings: The Key Factor in Mold Prevention—2nd Edition Heinz R Trechsel and Mark T Bomberg, Editors ASTM Stock Number: MNL18-2nd ASTM International 100 Barr Harbor Drive PO Box C700 West Conshohocken, PA 19428–2959 Printed in the U.S.A Library of Congress Cataloging-in-Publication Data Moisture control in buildings: the key factor in mold prevention/edited by Heinz R Trechsel, Mark T Bomberg—2nd ed p cm “ASTM stock number: MNL18-2nd.” Includes bibliographical references ISBN 978-0-8031-7004-9 Dampness in buildings—Prevention Waterproofing I Trechsel, Heinz R II Bomberg, Mark TH9031.M26 2009 693.8⬘93—dc22 2009016036 Copyright © 2009 ASTM International, West Conshohocken, PA All rights reserved This material may not be reproduced or copied, in whole or in part, in any printed, mechanical, electronic, film, or other distribution and storage media, without the written consent of the publisher Photocopy Rights Authorization to photocopy item for internal, personal, or educational classroom use, or the internal, personal, or educational classroom use of specific clients, is granted by ASTM International provided that the appropriate fee is paid to ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959; Tel: 610-832-9634; online: http://www.astm.org/copyright NOTE: The Society is not responsible, as a body, for the statements and opinions expressed in this publication ASTM International does not endorse any products represented in this publication Printed in Baltimore, MD October 2009 iii Acknowledgments First of all, the Editors wish to thank the chapter Authors for their contributions and hard work This book could not have been written by any one single author The field of moisture control is too large and varied and includes too many disciplines for one single person to master and to condense it all into a single volume Among the authors, Wayne Tobiasson was particularly helpful with his frequent and sorely needed encouragement and advice Wayne, much more than he probably realizes, is responsible for keeping the editorial and review process moving Your dedicated services are greatly appreciated The second large group of experts who performed an extremely valuable, essential, and unselfish service are the reviewers It really falls on them to carefully review the chapters for technical accuracy and relevance We are deeply indebted to all of them Also, without the dedicated and continuing support of Kathleen Dernoga and Monica Siperko of the Staff of ASTM International, the second edition of MNL18 would never have been possible Many thanks to both of you Finally, in the original conception of the first edition of MNL18, three personalities must be mentioned here for their invaluable assistance and encouragement Foremost Wayne Ellis, former chairman of ASTM, to whom the first edition was dedicated, Paul Reece Achenbach, former Director of the Building Environment Division of the National Bureau of Standards 共now NIST兲, who provided his great technical understanding of the entire concept of moisture control in buildings, and E.C Shuman, of Penn State University and former Chairman of ASTM Committee E06, whose long term association with the subject provided many historical insights Our heartfelt thanks to all three of them Unfortunately, they are no longer with us, but will be remembered for years to come Heinz R Trechsel and Mark T Bomberg Editors REVIEWERS: David E Allen Ervin L Bales Robert Bateman Robert Bombino Jon M Boyd Jan Carmeliet David B Eakin Fred R Eberle John R Edgar Earl A Ferguson John E Fernandez William Freeborne G Robert Fuller Stanley D Gatland Cynthia Gill John Grunewald Joseph R Hagan Andreas Holm John K Holton Thomas M Kenney Kevin Knight Peter Lagus Jared B Laurence Mark Lawton Sheldon J Leavit Kenneth Loefgren Joseph R Loferski Mary E McKnight Hugh C Miller William R Nash Peter E Nelson Thomas F O’Connor Donald M Onysko J Eric Peterson Helene Hardy Pierce Sylvio M Plescia Heinz F Poppendiek David Ritter Carsten Rode William B Rose Walter J Rossiter John A Runkle David W Saum Richard Scott Max H Sherman Paul H Shipp Baird Smith Steven Thorsell Martha G Van Geem Michael F Werner David W Yarbrough Contents Introduction Chapter 1—Fundamentals of Transport and Storage of Moisture in Building Materials and Components by Mavinkal K Kumaran vii Chapter 2—Hygrothermal Characteristics of Materials and Components Used in Building Enclosures by Mark T Bomberg and Clifford J Shirtliffe 16 Chapter 3—Effects of Moisture on the Thermal Performance of Insulating Materials by Per Ingvar Sandberg 38 Chapter 4—Moisture-Related Properties of Wood and the Effects of Moisture on Wood and Wood Products by Charles Carll and Alex C Wiedenhoeft 54 Chapter 5—Moisture, Organisms, and Health Effects by Harriet A Burge 80 Chapter 6—Exterior Climate Data for Hygrothermal Analysis by John F Straube 87 Chapter 7—Moisture Sources by Jeffrey E Christian 103 Chapter 8—Effects of Air Infiltration and Ventilation by Andrew K Persily and Steven J Emmerich 110 Chapter 9—Heating and Cooling Equipment by Russell M Keeler 117 Chapter 10—Design Tools by Anton TenWolde and Mark T Bomberg 128 Chapter 11—Measurement Techniques and Instrumentation by Vince Cammalleri and Peter L Lagus 139 Chapter 12—Investigating Moisture Damage Caused by Building Envelope Problems by Heinz R Trechsel and Niklas W Vigener 160 Chapter 13—Case Studies of Moisture Problems in Residences by George Tsongas 180 Chapter 14—General Principles for Design of Building Enclosures with Consideration of Moisture Effects by Mark T Bomberg, Heinz R Trechsel, and Paul R Achenbach 228 Chapter 15—Details and Practice by Peter Baker and Chris Makepeace 243 Chapter 16—Roofs by Wayne Tobiasson 297 Chapter 17—Moisture Control for New Residential Buildings by Joseph Lstiburek 342 Chapter 18—New Commercial, Institutional, and High-Rise Buildings by Gustav Handegord 364 Chapter 19—Recommendations for Remedial and Preventive Actions for Existing Residential Buildings by William B Rose 389 Chapter 20—Evaluation and Remediation of the Building Envelope for Existing High-Rise Buildings by Warren R French 399 Chapter 21—Manufactured Housing by Francis Conlin 428 Chapter 22—Moisture in Historic Buildings and Preservation Guidance by Sharon C Park 442 Chapter 23—Contract Documents and Moisture Control by Horace Calvin Crofford and Richard B Mundle 463 Chapter 24—Guidelines, Standards, and Codes by Theresa A Weston and Wayne P Ellis 472 Chapter 25—Quality Management in Design and Construction of the Building Envelope by Mario Tama 492 Chapter 26—Legal Considerations and Dispute Resolution: The Water-Related Construction Defect by Bruce W Ficken 566 Chapter 27—A Conceptual System of Moisture Performance Analysis by Mark T Bomberg and Cliff J Shirtliffe 581 Chapter 28—Towards Development of Methods for Assessment of Moisture-Originated Damage by Jan Carmeliet, Staf Roels, and Mark T Bomberg 591 Subject Index 606 vii Introduction Well-designed buildings have many virtues, among them the ability to serve their intended purposes and to become a beautiful and essential shelter for human activities Buildings also must resist various service loads, environmental stresses caused by temperature, humidity, wind and even those rare events of earthquakes or flooding They must also provide a healthy indoor environment eliminating air pollutants; and they must maintain these functions over the full intended service life Most of these attributes can be affected by moisture Uncontrolled moisture may reduce the structural soundness of buildings through dry rot in wood, corrosion in steel, freeze-thaw cycles in masonry, and other damage mechanisms Moisture also can affect the health of occupants typically through the potential for breeding harmful organisms With other words, uncontrolled moisture will negatively affect all the most vital attributes of buildings On the other hand, moisture reduces the shrinking cracks of wood and furniture, and up to a point, is necessary to avoid respiratory discomfort Thus, moisture is both a necessary constituency of our built environment and a potential liability The issue, then, is not to eliminate moisture from our buildings, but to control it and its movements Manual 18 addresses this general concept Over the 15 years since the publication of the first issue of MNL18, Moisture Control in Buildings, mold with its potential health effects have gained nationwide attention When the first edition of this manual was exhausted, the sponsoring ASTM Committees C16 and E06 agreed with the consensus of the chapter authors that the need for the manual actually had increased and that an updated version was needed All authors were given the option to the update or rewrite their chapters Those who were unable to the revision were replaced by equally qualified authors As in the previous edition, the manual does not provide all details and requirements of the many technologies involved in controlling moisture in buildings, but it is focused on the major issues involved in the design, and selection of materials and the process of moisture resistive construction Since the manual is a collection of chapters prepared by individual authors, the reader may find instances of repetition or even conflicts between the chapters To the extent that such conflicts reflect the current level of building science and of methods specific to moisture control in buildings, such conflicts were unavoidable In such an instance we recommend that the reader review the references to the chapters to form his/her own opinion Although many chapters include specific recommendations, the editors caution the reader that each building is different, that conditions of building service and climate are different Accordingly, no recommendations or details should be adopted without a careful analysis of the needs of the specific building Where analytical means exist, these should be tried in lieu of cookbook solutions Caution is advised as input data for material properties and weather data can be unreliable Many technical publications, research reports, and conference proceedings have been published on moisture control in buildings However, to our knowledge, this manual is the only publication which provides under one cover the most important information relating to moisture problems in buildings and to serve as a desk-top reference manual for use by those who design, construct, sell, maintain, and own buildings and homes To increase the completeness of the Manual, three new chapters were added: Chapter 15 on Details and Practice, Chapter 25, on Quality Management in Design and Construction of the Building Envelope, and Chapter 28 Towards Development of Methods for Assessment of Moisture-Originated Damage The details and practice should be helpful to design offices Quality management responds to a concern that the details and material selections may be carefully developed during design, but are sometimes not exactly followed when the on-site construction viii management organization does not understand the importance of a particular selection or design The last chapter and updated Chapter 27 look to the future We also dropped the chapter on modeling because ASTM MNL 40 on Moisture Analysis and Condensation Control in Building Envelopes, published in 2001, provides an in-depth state of the art of modeling But we did include a brief discussion of mathematical models in Chapter 10, Design Tools All other chapters were revised or updated, in some cases, such as Chapter 6, Exterior Climate Data for Hygrothermal Analysis, the revision led to what essentially is a new chapter The editors recognize that mechanical equipment has a significant impact on moisture control in buildings However, a thorough discussion of the issue would require an entire book all by itself Accordingly, we have included Chapter on mechanical equipment to emphasize the importance of mechanical equipment and its design and to illustrate one engineer’s thoughts on the issue The updated manual consists of four parts: Part 1, “Fundamentals,” discusses moisture transfer, condensation, and evaporation Moisture related properties of building materials, organisms and health effects, climate and moisture sources Part 2, “Applications,” discusses the technologies that affect the moisture balance in buildings and the techniques used to determine the suitability of materials, components, systems, and structures There are chapters on air infiltration and ventilation, design tools, measurement techniques and instrumentation, troubleshooting, and a chapter on case studies Part 3, “Construction Principles and Recommendations” includes discussions of and recommendations to make both new and existing commercial and high buildings, new and existing residential buildings, as well as manufactured and historic buildings One chapter is devoted to suggested construction details and one discusses roofing Part 4, “Implementation,” discusses implementation mechanisms This section is organized along a simple concept: First, the building should be designed, built, and repaired in accordance with the contract documents which contain the principles outlined in the earlier sections and chapters Second, codes and standards provide a firm basis for selecting products, systems, and construction features Third, in the design office and on the construction site, the principles of recognized quality management must be observed to assure that what is constructed complies fully with the contract documents And finally, when all else fails, there are arbitration and court proceedings to resolve conflicts Each of these mechanisms is discussed to give the reader a good understanding of the process beyond just a good design and adequate specifications The Manual closes with a look to the future and a discussion of a Conceptual System of Moisture Performance Analysis The editors would appreciate receiving any comments or criticisms, but they also hope that the second edition of MNL18 be as well received as the first edition was Heinz R Trechsel and Mark T Bomberg Editors MNL18-EB/Oct 2009 Fundamentals of Transport and Storage of Moisture in Building Materials and Components Mavinkal K Kumaran1 WATER, WHICH IS ABUNDANT ON OUR PLANET, naturally undergoes various physico-chemical processes and interacts with all living and nonliving entities As much as water is essential for all life forms, it can also cause the degradation of many natural and manmade materials This may be due to chemical, biological, or mechanical processes undergone by the material as a result of its interaction with water Corrosion of metals is an example for chemical deterioration, decay of wood and wood-based material for biological, and cracking and spalling of masonry material for mechanical Buildings that are constructed to last many decades include a number of materials that are susceptible to deterioration due to their interaction with moisture Hence, building researchers, designers, and practitioners have always been interested in the role of moisture in the built environment The scientific and technical knowledge that is necessary to understand and interpret the consequences of the interaction between moisture and building materials was originally based on the work done by soil scientists 关1–3兴 In such an approach, building materials are regarded as porous bodies, like soil The analogy is useful, but inadequate for building applications Materials in the built environment simultaneously experience three inter-related transport processes: • Heat transport • Moisture transport • Air transport The last is often not an issue in soil science During the past three decades or so, the approach from soil science was extended to understand the combined heat, air, and moisture 共HAM兲 transport in building materials and components through major international collaborations 关4–6兴 and through the efforts of researchers at major building research organizations The knowledge that is available today can reasonably well answer questions such as: How can the transport of heat, air, and moisture through building materials and components be predicted? How can the harmful accumulation of moisture in building materials and components be prevented? How air and moisture transports affect the energy efficiency of buildings? More recently completed international collaborations 关7兴 are expected to apply the knowledge to improve HAM analyses at the whole-building level Over the past three decades significant advances have been made in the experimental and analytical methods to determine the hygrothermal behavior of building materials and components as influenced by HAM interactions 关8–14兴 Later chapters in this handbook deal with various aspects of hygrothermal behavior of building materials, components, and systems individually This chapter is intended to summarize our present knowledge of moisture storage and transport in building materials This knowledge is fundamental to understand the complex interaction of heat, air, and moisture transport in the built environment The Thermodynamic States of Moisture H2O 共or moisture兲, like any other pure substance, can exist in three states: solid 共ice兲, liquid 共water兲, and gas 共water vapor兲 These three states of moisture can exist in buildings, depending upon the geographic location In addition, the various building materials can capture water molecules from the surrounding air and localize them on their surfaces Moisture so localized is said to be in an adsorbed state In the absence of another material, the equilibrium between solid, liquid, and vapor is well defined At any given temperature there is a well-defined maximum vapor pressure that moisture can establish This maximum vapor pressure is called the saturation vapor pressure at that temperature There is only one temperature and saturation vapor pressure at which all three states can coexist This coexistence is referred to as the triple point of water The triple point temperature for water is 273.16 K and the corresponding saturation pressure is 611 Pa At any other temperature, T, between 250 K and 330 K the following two equations yield the saturation vapor pressure, pv, within a fraction of a percent 共pv/Pa兲 = exp兵28.542 − 5869.9/共T/K兲 − 2882/共T/K兲1.5其 for 250 K ⬍ T ⬍ 273.16 K 共1兲 Principal Research Officer, Institute for Research in Construction, National Research Council Canada, Ottawa K1A 0R6, Canada E-mail: kumar.kumaran@nrc.gc.ca Copyright © 2009 by ASTM International www.astm.org 598 䊏 MOISTURE CONTROL IN BUILDINGS - 2ND EDITION a validated HAM 共heat, air, moisture兲 transport model; moisture transport characteristics, i.e., the moisture storage and permeability 共moisture conductivity兲 for all materials involved in the analyzed building assembly Requirements for numerical HAM models and its validation are formulated by an international group and discussed by Hagentoft et al 关44兴 More difficult is, however, ensuring that the moisture transport properties used in the HAM simulation are adequate for the given analysis This difficulty stems from two reasons: • each HAM model uses individually tailored sets of material characteristics, • despite research 关45–47兴 and despite an international proposal of recommendations for material characterization 关48兴, recent hygrothermal databases include materials characteristics, which are not characterized in a fully rigorous manner As an example, we mention the calculation of permeability from diffusivity and moisture retention curve leading to unrealistic values • For numerical modeling, material characteristics in functional form are advantageous Which functions are most favorable to describe the moisture transport properties is still a matter of scientific debate Moreover, the parameters describing these functions are until now only available for a limited number of materials When functional descriptions of moisture transport characteristics are unavailable, tabular data 共data points兲 with possible interpolation between them are still most often used On the other hand substantial progress has been made both on the scientific and engineering level to develop a consistent methodology of material characteristics determination First, we give a short overview of scientific advances in moisture transport modeling Then, we present an engineering approach based on the work of Grunewald et al 关49兴 and Scheffler et al 关50兴 The moisture capacity is defined as the derivative of the moisture content curve to the driving potential: w / pc or w / with w the moisture content, pc the capillary pressure, and the relative humidity Necessary data can be obtained by a combination of different measurement techniques including pressure plate technique, mercury intrusion, micrography, and sorption isotherms 关46,51兴 Carmeliet and Roels 关52兴 compared different parametric functions for describing the moisture capacity and showed that bimodal functions are preferable for approximating the moisture capacity both in hygroscopic and over-hygroscopic regions To limit the experimental effort, a minimal number of optimally located data points is needed to identify the parameters A model based on the presence of inkbottle pore systems was successfully applied to explain and predict hysteresis in moisture properties 关45,53兴 Descamps 关54兴, Carmeliet et al 关55兴, and Carmeliet and Roels 关56兴 proposed a multiscale pore network model as a practical method for estimating the moisture permeability covering hygroscopic and over-hygroscopic region including both water vapor and liquid water transfer The proposed method requires as input the pore volume distribution 共or capillary pressure curve兲, the capillary absorption coefficient and the water vapor permeability, as determined by standard experiments Carmeliet et al 关57兴 proposed a new • • Fig 10—Average 共top兲 and surface 共bottom兲 moisture contents of the ceramic brick for Southwest orientation 共location center兲 in December: variable ␣, constant ␣ as given in Janssen et al 关30兴, and ␣ according to prEN 13013-3 关28兴 posed to derive more accurate constant ␣-values from the ␣共Rh , U cos 兲 chart We observe that these constant ␣-values give better approximations compared to the constant ␣-values as given by prEN 13013-3 关28兴 However, when analyzing possible runoff of rainwater on building facades, a time varying ␣-value is favorable This means that for future use of driving rain as a boundary condition in numerical HAM models, a database of ␣共Rh , U cos 兲 charts for different locations on different building types should be developed and connected to the existing HAM models The prediction of wind-driven rain loads on building facades has been applied to the estimation of wind-driven rain infiltration loads For example, Teasdale-St-Hilaire et al 关41,42兴 have developed a deterministic approach for a wetting methodology that simulates wind-driven rain infiltration for building envelope hygrothermal testing In the methodology, water is inserted into the wall structure behind the cladding in a dropby-drop fashion at a rate, frequency, and duration determined by a statistical analysis of long-term hourly weather data The fraction of water that infiltrates through an intentional envelope defect is found by conducting a water leakage test based on ASTM E331-00共2009兲 关43兴 Advanced Modeling of Moisture Transport Characteristics Essential to a correct numerical prediction of the moisture response of building materials and components is: CHAPTER 28 methodology for determining the liquid water diffusivity from the measured moisture content profiles A critical overview of different nondestructive techniques for measuring the time evolution of moisture content profiles during water uptake is given in Roels et al 关58兴 These authors also propose a parametric description for the moisture diffusivity covering both hygroscopic and overhygroscopic regions In the engineering moisture transport model 关49兴, a minimal set of parameters for hygrothermal material characterization as input to HAM simulation programs is proposed These basic parameters are determined in standard experiments: bulk density, porosity, thermal conductivity, sorption and retention data, water uptake experiments, water vapor diffusion, and drying experiments The determination of the material model is based on a three-step approach: Moisture capacity: selection of suitable material functions with sufficient flexibility to describe the nonlinear dependency 共e.g., Gauss probability functions兲 In this step the moisture storage function is adjusted to measurement data Moisture transport characteristics In this step a simple pore model is used to derive a conductivity 共permeability兲 function, which is further calibrated with the capillary uptake experiment and water vapor permeability measured at high RH The functional parameters are determined by indirect comparing the measured and simulated moisture response Validation Comparison between measured and predicted behavior from experiments not having used for the identification Isothermal drying experiments are used for this purpose Advanced Modeling of Coupled Moisture Transport and Damage Processes in Porous Building Materials and Structures Poroelasticity In this section, we present the poromechanical approach for taking into account the influence of moisture on the elastic behavior of porous materials In Eq 共5兲 the classical approach of introducing moisture effects using initial or free strains was presented This approach, however, does not fully account for all coupling effects between moisture and mechanical behavior: changes in moisture saturation lead to a change in stiffness, strength, and to swelling or shrinkage Using an uncoupled approach, these effects are described by empirical law, which requires intensive experimental testing These moisture influences, however, originate from the same physical mechanisms situated at lower material scale The poroelasticity offers a theoretical framework to take into account all coupling effects in a thermodynamically consistent manner Porous materials such as concrete and rocks are hydrophilic porous materials and contain a substantial specific pore surface area As a result, they exhibit intense fluid-solid interactions because of molecular and surface forces The induced forces are known to be extremely sensitive to the saturation level Solid-fluid interaction forces are due to molecular adsorption forces along pore walls 关59兴, water film pressure or spreading pressure 关60兴, microscopic capillary pressures due to surface tension effects, and swelling 共disjoining or interlayer兲 pressures due to the presence of inter- 䊏 TOWARDS DEVELOPMENT OF METHODS 599 Fig 11—Building of water menisci on the rough pore surface and surface tension effects at two different pore relative humidities At low saturation 共a兲 many menisci exist with low radius leading to high compressive prestresses to the solid matrix At higher saturation 共b兲 the radius increases and the amount of menisci decreases, leading to lower compressive prestresses layer water, e.g., in the laminar sheets of C-S-H 共calciumsilicate-hydrate兲 in concrete 关61–64兴 Note that all these pressures are in reality 2-D interface or surface stresses Pore pressures, due to the pressurization of the free pore water, are not considered in this paper since they are not governed by fluid-solid surface forces First, let us review in more detail the effect of surface tension effects 共capillary pressure兲, when water menisci build up in the porous material with increasing pore relative humidity The pore surface can be considered as a very rough surface with a lot of possible places for building up water menisci or membranes introducing surface tension effects 共Fig 11兲 Commonly it is assumed that liquid water perfectly wets the solid 共the contact angle equals 0°兲 Then ␥lg = ␥sg共 = ␥兲 and ␥sl = 0, with ␥␣ the surface tension in the ␣ interface 共the subscript s refers to solid, g to gas, and l to liquid phase兲 Laplace’s law describes the capillary pressure over the liquid water–water vapor interface pc = pg − pl = 2␥ R 共8兲 with R the radius of the spherical meniscus and ␥ = ␥lg Since water is in tension the solid matrix will be exposed to compressive forces due to the action-reaction principle At low relative humidity, we observe a large number of possible sites for membranes to build up 共Fig 11共a兲兲 The membranes at these places have a relatively low equivalent radius R Therefore, high compressive forces 共or prestresses兲 are present As the degree of saturation increases, the radius of the spherical membrane increases and at the same time the number of sites decreases 共Fig 11共b兲兲 This results in an important decrease of the compressive prestresses with increasing degree of saturation Next, we will assume that all pore water in the microstructure is locally in thermodynamic equilibrium Therefore, changes in microscopic capillary pressure will almost instantly result in changes of microscopic spreading pressure, swelling pressure, and interlayer water pressure The net result of all moisture induced microstresses on the liquid can then be expressed at the macroscale by one macroscopic liquid pressure pl This macroscopic liquid pressure can be seen as the average result of all the microscopic pressures acting at the pore scale Assuming the gaseous phase in thermodynamic equilibrium with the outside 共pg at constant atmospheric pressure兲 the macroscopic liquid pressure pl can be replaced by the macroscopic capillary pressure pc, which 600 MOISTURE CONTROL IN BUILDINGS - 2ND EDITION 䊏 is commonly used in fluid transport modeling 关65兴 In this context, the macroscopic capillary pressure can be considered to be representative of the combined effects of all complex microscopic fluid-solid interaction forces All fluid-solid interaction forces show a tendency from high compressive prestresses 共or low tensile prestresses兲 to low compressive prestresses 共or high tensile prestresses兲 as saturation increases As usually assumed, when upscaling these microstresses to the macroscale, the deviatoric prestresses completely balance and vanish Only hydrostatic prestresses due to fluid-solid interaction are considered Assuming isotropic, homogenous, and isothermal behavior, the incremental constitutive equation reads d = K共,pc兲d + b共,pc兲dpc 共9兲 with the hydrostatic stress, the volumetric strain, K the tangent drained bulk modulus, pc the capillary pressure, and b the tangent Biot or coupling coefficient The tangent coupling coefficient b is normally proportional to the degree of saturation S 冉 b= 1− 冊 K S = b ⬘*S Ks 共10兲 with Ks the bulk modulus of the solid matrix We assumed in Eq 共9兲 that the gas pressure in the ideal mixture 共water vapor and dry air兲 is in equilibrium with the environment and remains constant, or dpmix = The study is limited to isothermal isotropic and uniaxial experiments In this case, Eq 共9兲 becomes d11 = E共pc兲d11 + 共1 − 2兲b⬘*S共pc兲dpc 共11兲 with E the isothermal Young’s 共tangent兲 modulus dependent on the capillary pressure and the Poisson ratio 共which we assume to be independent of the capillary pressure兲 The relation between degree of saturation and capillary pressure is described by the capillary pressure curve S共pc兲 Integrating Eq 共11兲 we get 11 = E共S兲11 + b⬘共1 − 2兲 冕 S共pc兲dpc 共12兲 pc Let us now perform a free swelling/shrinkage experiment A specimen is allowed to freely shrink/swell when changing the relative humidity, or d11 = According to Kelvin’s law changes in relative humidity can be related to changes in capillary pressure d = − dpc lR vT 共13兲 with Rv the gas constant for water vapor, T the absolute temperature, and l the volume density of liquid water Using Eqs 共11兲 and 共13兲 with d11 = 0, the swelling strain increment becomes d11 = b⬘lRvT S共兲 d = 共兲d 共1 − 2兲E共S兲 共14兲 The coefficient  can be interpreted as the shrinkage coefficient which, according to the equation, is a function of the relative humidity, the stiffness of the material, and the coupling coefficient, which are parameters with a clear physical significance In Fig 12共b兲 the hygric strain predicted accord- Fig 12—共a兲 Experimental and fitted hygroscopic curve for cellulose fiber cement 共b兲 Comparison of the measured and predicted hygric strain ing to Eq 共14兲 is compared to the experimental hygric strain as obtained in a free swelling experiment 关66兴 The material is a cellulose fiber cement composite The elastic modulus was measured in a tensile experiment and equal to 12,370 MPa The Poisson ratio is equal to 0.25 The coupling coefficient b⬘ is found to be 0.79 The result shows the ability of the poroelastic theory to predict hygric shrinkage based on material properties with a physical meaning Modeling Moisture Originated Damage Using Mixed Discrete and Continuum Approaches Poroelasticity offers a framework to include moisture effects on the mechanical behavior of porous materials Recently, poromechanical models have been extended to take into account damage and fracture processes Poromechanical approaches are coupled to damage-plasticity models 关67–71兴 Based on these concepts, a coupled chemomechanical model describing chemical expansion 关72兴 and calcium leaching 关73兴 in saturated porous media has been formulated These damage-plasticity models are continuum models, where localization in a macrocrack is handled using smeared or higher order approaches The penetration of fluids through cracks is usually modeled by an increased per- CHAPTER 28 䊏 TOWARDS DEVELOPMENT OF METHODS 601 Fig 13—Flow chart for the coupled discrete/continuum model meability in a certain zone, using empirical laws based on average crack widths Drawback of a continuum model is that a crack strain over a band governs the damage process rather than a crack width In this way the continuum model does not take into account the peculiar features of cracks with varying width and connectivity, which may highly influence the resulting permeability,see Ref 关74兴 among others Apart from that, when trying to model the steep moisture fronts in the fracture, one is confronted with numerical instabilities 关75兴 This is a result of the highly nonlinear nature of the constitutive relationships and the strong contrast between physical transport properties of fractures and matrix To overcome this problem Roels et al 关76兴 presented a discrete model for the simulation of cracking and liquid flow in fractures This discrete model for the fracture is coupled to poromechanical continuum models, describing the mechanical behavior and transport in the uncracked porous matrix 共Fig 13兲 The discrete model for the damage process is a partition-of-unity 共PU兲 crack model 关77兴 Cracks are modeled as displacement continuities, which can run freely through the finite element mesh To simulate moisture transport in the fractured porous matrix, a 1-D discrete model for liquid flow in a fracture is combined with a finite element model that solves the unsaturated liquid flow in the uncracked matrix 关78兴 To exemplify the potential of the proposed model, we show the load-deflection curves for a beam at different uniform moisture content subjected to three point bending 共Fig 14兲 The material is Berea sandstone A Fig 14—The influence of a different 共uniform兲 degree of saturation on the mechanical response during a three point bending test With increasing saturation the maximal force diminishes and the damage behavior becomes more and more ductile Fig 15—Simulated moisture uptake in a loaded beam showing a macrocrack The preferential wetting around the fracture is clearly observed substantial decrease of the maximal force can be noted with increasing moisture content Furthermore, the response curves become more and more ductile when saturation increases In a second example the beam is first loaded until cracking appears Then, the beam is brought in contact with a free water plane at the bottom side The moisture content profiles in the beam are given in Fig 15 The waterfront in the fracture reaches the top side of the fracture in less than a second From then on the fracture acts as an extra water source for the surrounding matrix over almost the total height of the beam Conclusions from the Review of the Recent Developments The durability assessment includes the estimation of the probability of failure over the design life Such an approach is based on the following steps: identification of the mechanism’s response and deterioration, formulation of a mathematical model describing the mechanical loads and environmental actions as well as the resulting deterioration processes, the choice of appropriate durability indicators, and the statistical description of the basic variables Finally, the service life function is evaluated using a stochastic calculation method Different types of durability indicators may be used: a single occurrence of exceeding a critical level, the number of occurrences that a critical condition is exceeded, and the critical cumulative exposure Currently, the durability assessment is mainly based on the analysis of the hygrothermal response of building material or component Damage based assessments are clearly superior leading to a more accurate prediction of the service life of the building component Damage based approaches account both for the time dependence of hygrothermal response, and damage process They can account for the coupling between hygrothermal loading, hygrothermal response and damage process One may choose a more appropriate damage criterion and account for the statistical nature of hygrothermal response and damage process The damage based methods necessitate not only a HAM transport model, but also the coupling to a damage evolution 602 MOISTURE CONTROL IN BUILDINGS - 2ND EDITION model Coupled heat and mass transport and 共continuum兲 damage models have been developed in the framework of poromechanics More recently, discrete damage and transport models have been developed in a consistent manner taking into account, e.g., preferential flow in cracked media Furthermore, this chapter reported new developments for prediction of driving rain loads on building facades and progress on determination of moisture transport properties Further Needs: Towards a Methodology for Integrated HAM Performance Assessment In the preceding chapter we presented current developments in durability assessment The need for further research in damage modeling coupled to HAM models was addressed However, also in HAM modeling further developments are needed The further needs in HAM research are addressed in this section The current numerical models to evaluate the hygrothermal behavior of building enclosures evolved from the Glaser method and, although commonly referred to as HAM-models 共heat, air, and moisture兲, the influence of air transfer on the heat and moisture transport processes is still often neglected A major reason is the vastly different timescales of the transport processes that pose severe problems in the numerical calculations Use of a stabilized solution method for the transfer equations should, however, allow incorporating air transfer in hygrothermal simulations Correct airflow analysis requires a correct implementation of the outside boundary conditions Nowadays often a climatic data file of a nearby weather station is used, neglecting important local phenomena as differential air pressure differences and differential driving rain loads over the building envelope, film forming and run-off, differential solar radiation, and shadowing In perspective of modeling airflows through envelopes and optimizing ventilation strategies, a correct prediction of the distribution of the air pressure differences is a prerequisite Because of economical benefits, the use of CFD will become more and more widely used However, and in particular, for structures with specific geometry 共sharp shapes/edges兲 there is an important lack of validated situations on the basis of full-scale measurements This is crucial for high wind speed regimes 共with a focus on gust wind pressures on the building兲 but also for low wind speed regimes 共for ventilation and comfort-related issues兲 Regarding driving rain, a lot of progress has been made in the analysis and prediction of driving rain load on building facades However, a thorough analysis of the influence of geometric details present in the facade such as small projections and of the influence of the surrounding environment 共microclimate兲 on the driving rain load is lacking Therefore, a first need is the detailed prediction of the microclimatic driving rain load Furthermore, a correct incorporation of all contact and surface phenomena remains a missing link between the prediction of driving rain load over the building envelope and the hygrothermal simulations of the building enclosures In relation to driving rain, leakage as possible internal moisture source for building enclosures has to be taken into account There is still a need for a scientificallybased methodology for durability assessment when dealing with risks for leakage 䊏 Also the indoor environment in HAM-models often only interferes as a simplified boundary condition To more accurately predict indoor heat-air-moisture conditions integrated building simulation models are needed At the moment, the main issue of building simulation models is the prediction of thermal conditions inside the building and of total energy consumption of the building If included, moisture issues are commonly simplified to vapor transport and a certain moisture storage capacity of the interior Recently, some steps have been made to merge building simulation models and hygrothermal building envelope models 关79兴 At the same time, advances in computational fluid dynamics 共CFD兲 showed its possibilities to simulate bulk airflow both inside and around buildings The current lack of a fully integrated approach towards building heat, air, and moisture engineering still impedes an adequate performance prediction for several applications As an example, we mention the design of lightweight building constructions The performances of lightweight building assemblies are extremely sensitive to convective heat and vapor transfer resulting from air leakage through the joints, cracks, and perforations, common to most existing methods of construction In order to come to an adequate control of heat and moisture transfer in lightweight building components, the modeling capabilities of the existing HAM-tools should be coupled with models for the interior and exterior climate 共indoor moisture load, indoor air pressure, gradients of wind pressure…兲 Accurate model predictions may form the basis for design criteria for air barriers, wind barriers, underlay systems, etc The major need for a whole building performance analysis concerns the simultaneous prediction of the temperature and humidity conditions of the indoor air and of the materials in the building envelope and interior This asks for a correct coupling between indoor climate, building envelope, and outside climate Hereby, building enclosures may no longer be treated as isolated, one-dimensional homogeneous components, but the interaction of the different building envelope parts on one another—as linked by the indoor environment—has to be incorporated Therefore a first need is to model internal bulk flow in and between rooms Current modeling can be categorized into three approaches with increasing resolution and complexity: 共1兲 Building energy balance models 共BES兲 that basically rely on guessed or estimated values of airflow; 共2兲 Zonal airflow network 共AFN兲 models that are based on 共macroscopic兲 zone mass balance and inter-zone flow-pressure relationships typically for a whole building; and 共3兲 CFD that is based on energy, mass, and momentum conservation in all 共minuscule兲 cells that make up the flow domain 共typically a single building zone兲 Regarding CFD, a lot of progress has been made in this field, but a reliable conflation of CFD, building simulation, and HAM envelope models is not so straightforward and remains extremely time consuming Water vapor transport from/to walls and interior elements 共so-called moisture buffering兲 is only recently taken into account in the moisture balance 关79兴 In order to use CFD for modeling HAM transport in buildings, classical CFD has to be extended and coupled to a HAM transport model for porous materials Current stateof-the-art CFD does not offer the possibility to describe in an efficient and satisfying manner the interaction between fluid CHAPTER 28 and solid material 共boundary layer problem兲 for complex geometries In these cases, the boundary layer problem can only be solved using very fine grids leading to unreasonable calculation times The time constants of the convective 共sensible兲 and latent heat transport differ an order of magnitude, leading to specific problems in attaining stable numerical solutions Also moisture transport in porous materials adds a third time scale The enrichment of classical CFD to a CFDHAM model and the formulation of efficient solutions strategies necessitates an in-depth study So, although the need for whole building performance engineering is obvious, the challenge will be how to integrate or couple the different numerical models We define coupled 共integrated兲 simulation as two 共or more兲 separate simulation tools, each of them solving a separate set of equations, exchanging time-step data in a prescribed manner A coupled simulation usually involves the following components: 共1兲 domain solvers: it must be clear which numerical code calculates which terms in the overall solution scheme; 共2兲 geometry modeler and grid generator or both; 共3兲 master program which coordinates the coupling procedure, e.g., frequency and point in the solution procedure where data are exchanged between the codes, definition of the variables that will be passed between the codes, method of time step control Based on the interaction between the domain solvers, we further categorize coupled simulation into two categories: internal coupling, where the domain application is tailored to work specifically within a certain environment Usually the code needs to be rewritten for this; and external coupling, where the domain application is not changed to cooperate with other domain application External coupling is advantageous because of two main reasons: 共1兲 individual domain applications have evolved separately over the years and are well proven Making these different domain applications to communicate with each other would be a great advance to the building industry Rewriting the code can be seen as a setback from these independent advances in the separate domains 共2兲 Each individual domain can be developed further independently There is no need to worry about keeping up with the latest development in each domain Let each domain expand and progress in their respective directions As it is known how the domains can communicate with each other, it is possible to take advantage of these latest developments REFERENCES 关1兴 关2兴 关3兴 IEA-Annex 32, “Building Envelopes in a Holistic Perspective,” International Energy Agency 共IEA兲, Energy Conservation in Buildings and Community Systems 共ECBCS兲, Annex 32, Task A, Leo Hendriks and Hugo Hens, Laboratorium Bouwfysica, K.U Leuven, Leuven Hens, H and Carmeliet, J., “Performance Prediction for Masonry Walls with EIFS Using Calculation Procedures and Laboratory Testing,” Journal of Thermal Envelope and Building Science, Vol 25, 2002, pp 167–187 IEA-Annex 24, “Heat, Air, and Moisture Transfer through New and Retrofitted Insulated Envelope Parts 共Hamtie兲,” International Energy Agency 共IEA兲, Energy Conservation in Buildings and Community Systems 共ECBCS兲, Annex 24, Task 5: “Performances and Practice, The Impact of Heat, Air and Moisture Transport on Energy Demand and Durability,” CarlEric Hagentoft, Laboratorium Bouwfysica, K.U Leuven, Print Acco Leuven, 1998 䊏 关4兴 关5兴 关6兴 关7兴 关8兴 关9兴 关10兴 关11兴 关12兴 关13兴 关14兴 关15兴 关16兴 关17兴 关18兴 关19兴 关20兴 关21兴 关22兴 TOWARDS DEVELOPMENT OF METHODS 603 Bomberg, M and Allen, D., “Use of Generalized Limits State Method in Design of Building Envelopes for Durability,” J Thermal Ins and Bldg Envs., Vol 20, July 1996, pp 18–39 Allen, D and Bomberg, M., “Limits State Method in Design of Building Envelopes for Durability,” 7th Canadian Building Science and Technology Conference, Toronto March 20–21, 1997 Mehta, P K., “Durability-Critical Issues for the Future,” Concr Int 1997, pp 27–33 Harderup, E., “Methods for Determining of the Risk of Critical Moisture Conditions with Natural External Climate,” Proceedings Building Physics in the Nordic Countries, VTT, Finland, 1996 Gertis, K., Kiessl, K., Nannen, D., and Walk, R., “Wärmespannungen in Thermohaut-Systemen Voruntersuchung unter idealisierten Randbedingungen,” Die Bautechnik, Vol 5, 1983, pp 155–162 Nannen, D and Gertis, K., “Thermische Spannungen in Wärmedämmverbund-systemen,” Bauphysik Vol 6, No 4, 1984, pp 126–136 Fink, R., Eigenspannungen in Zweischichtsystemen, Bauphysik, Vol 13, No 3, 1991, pp 85–91 Fagerlund, G., “Assessment of the Service Life of Materials Exposed to Frost,” Div of Building Materials, Lund University, Sweden Durability of Building Materials and Components 7, Stockholm Sweden, May 1996 Bomberg, M T and Shirtliffe, C J., “A Conceptual System of Moisture Performance Analysis,” Manual on Moisture Control in Buildings, ASTM Manual 18, ASTM International, West Conshohocken, PA, 1994, pp 453–461 Hukka, A., and Viitanen, H., “A Mathematical Model of Mold Growth on Wooden Material,” Wood Sci Technol Vol 33, No 6, 1999, pp 475–485 Kumaran, M K., Mukhopadhyaya, P., Cornick, S., Lacasse, M., Maref, W., Rousseau, M., Nofal, M., Quirt, J., and Dalgliesh, W., “A Methodology to Develop Moisture Management Strategies for Wood-frame Walls in North America: Application to Stucco-clad Walls,” 6th Symposium on Building Physics in the Nordic Countries, 2002 Baker, P., Hunter, C., Galbraith, G H., McLean, R C., and Sanders, C., “Measurement and Prediction of Indoor Microenvironment for the Control of Biocontaminants,” CIB W40 Conference Papers, Centre for Research on Indoor Climate and Health, School of Engineering, Science and Design, Glasgow, 2004 Janssens, A., “Reliable Control of Interstitial Condensation in Lightweight Roof Systems,” Ph.D Thesis, Katholieke Universiteit Leuven, Departement Burgerluke Bouwkunde, Leuven, Belgium, 1998 Sedlbauer, K., Vorhersage von Schimmelpilzbildung auf an in Bauteilen, “Prediction of Mold Manifestation On and In Building Parts,” Dissertation Universität Stuttgart, 2001 Karagiozis, A and Salonvaara, M., “Parametric Study on Material Properties Using Stochastic Modeling,” IEA Annex 24 Task 1: Simplified Modeling Nielsen, A., “Use of Statistics for Prediction of Risk for Condensation in a Wall Construction,” Moisture Problems in Building Walls, Porto CIB W40 Meeting, 1985 Holm, A., “Ermittlung der Genauigkeit van instationären hygrothermischen Bauteilberechnungen mittels eines stochastischen Konzeptes,” Dissertation Universität Stuttgart, 2001 Harderup, L.-E., “Simplified Statistical Method to Determine the Risk of Condensation by Diffusion in Building Elements,” Proceedings of the 5th Symposium on Building Physics in the Nordic Countries, Chalmers University of Technology, Göteborg, Sweden, 1999, pp 537–544 Pietrzyk, K., “Probabilistic Modeling of Air Infiltration and 604 关23兴 关24兴 关25兴 关26兴 关27兴 关28兴 关29兴 关30兴 关31兴 关32兴 关33兴 关34兴 关35兴 关36兴 关37兴 关38兴 关39兴 关40兴 MOISTURE CONTROL IN BUILDINGS - 2ND EDITION Heat Loss in Low-rise Buildings,” Ph.D Thesis, ISBN 917197-961-1, Chalmers University of Technology, Gothenburg, Sweden, 2000 Pietrzyk, K., Kurkinen, K., and Hagentoft, C.-E., “An Example of Application of Limit State Approach for Reliability Analysis of Moisture Performance of a Building Component,” Journal of Thermal Envelope and Building Science, Vol 28, 2004, pp 9–26 Carmeliet, J., and de Borst, R., “Gradient Damage and Reliability: Instability as Limit State Function,” Framcos-2, 2nd Conference on Fracture Mechanics of Concrete and Concrete Structures, F H Wittmann, Ed., Aedificatio Publ., 1995, pp 1011–1021 Zheng, R., “Performance of Highly Insulated Zinc Roofs in Moderate Humid Regions,” Ph.D Dissertation, Leuven, K.U.Leuven, 2004 Reinhardt, H W., “Penetration and Permeability of Concrete, Barriers to Organic and Contaminating Liquids,” Rilem Report 16, E&FN Spon, 1997 Carmeliet, J., “Durability of Fiber Reinforced Renderings on Outside Insulation: A Probabilistic Approach Based on Nonlocal Damage Theory,” Ph.D Thesis, Laboratory of Building Physics, K.U Leuven, Belgium, 1992 prEN 13013-3, “Hygrothermal Performance of Buildings— Climatic Data—Part 3: Calculation of a Driving Rain Index for Vertical Surfaces from Hourly Wind and Rain Data 共prenormative text兲,” 1977 Blocken, B., “Wind-driven Rain on Buildings—Measurements, Numerical Modeling and Applications,” Doctoral Dissertation, Katholieke Universiteit Leuven, Belgium, 2004 Janssen, H., Blocken, B., Roels, S., and Carmeliet, J., “Winddriven Rain as a Boundary Condition for HAM Simulations: Analysis of Simplified Modeling Approaches,” submitted to Build Environ 2004 Blocken, B., and Carmeliet, J., “Driving Rain on Building Envelopes—I: Numerical Estimation and Full-scale Experimental Verification,” Journal of Thermal Envelope and Building Science, Vol 24, No 1, July 2000, pp 61–85 Blocken, B and Carmeliet, J., “Driving Rain on Building Envelopes—II: Representative Experimental Data for Driving Rain Estimation,” Journal of Thermal Envelope and Building Science, Vol 24, No 2, Oct 2000, pp 89–110 Blocken, B and Carmeliet, J., “Spatial and Temporal Distribution of Driving Rain on a Low-rise Building,” Wind Struct Vol 5, No 5, 2002, pp 441–462 Blocken, B., and Carmeliet, J., “A Review of Wind-driven Rain Research in Building Science,” J Wind Eng Ind Aerodyn Vol 92, 2004, pp 1079–1130 Choi, E C C., “Simulation of Wind-driven Rain Around a Building,” J Wind Eng Ind Aerodyn Vols 46 and 47, 1993, pp 721–729 Wisse, J A., “Driving Rain, a Numerical Study,” Proceedings of 9th Symposium on Building Physics and Building Climatology, Dresden, Sept 14–16, 1994 Karagiozis, A., Hadjisophocleous, G., and Cao, S., “Winddriven Rain Distributions on Two Buildings,” J Wind Eng Ind Aerodyn Vols 67 and 68, 1997, pp 559–572 Van Mook, F J R., “Driving Rain on Building Envelopes,” Ph.D Thesis Building Physics Group, 共FAGO兲, Eindhoven University of Technology, Eindhoven University Press, Eindhoven, The Netherlands, 2002, 198 pp Etyemezian, V., Davidson, C I., Zufall, M., Dai, W., Finger, S., and Striegel, M., “Impingement of Rain Drops on a Tall Building,” Atmos Environ Vol 34, 2000, pp 2399–2412 Janssen, H., “The Influence of Soil Moisture Transfer on Building Heat Loss Via the Ground,” Doctoral Dissertation, Katholieke Universiteit Leuven, Belgium, 2002 䊏 关41兴 关42兴 关43兴 关44兴 关45兴 关46兴 关47兴 关48兴 关49兴 关50兴 关51兴 关52兴 关53兴 关54兴 关55兴 Teasdale-St-Hilaire, A., Derome, D., and Fazio, P., “Development of an Experimental Methodology for the Simulation of Wetting Due to Rain Infiltration for Building Envelope Testing,” Proceedings of the 2nd International Building Physics Conference, Balkema, Leuven, Belgium, Sept 14–18, 2003, pp 455–462 Teasdale-St-Hilaire, A., Derome, D., and Fazio, P., “Behavior of Wall Assemblies with Different Wood Sheathings Wetted by Simulated Rain Penetration,” Performance of Exterior Envelopes of Whole Buildings IX: International Conference, ASHRAE, Clearwater Beach, FL, Dec 5–10, 2004, 15 pp ASTM Standard E331–00共2009兲, “Standard Test Method for Water Penetration of Exterior Windows, Skylights, Doors, and Curtain Walls by Uniform Static Air Pressure Difference,” Annual Book of ASTM Standards, ASTM International, West Conshohocken, PA, 2000 Hagentoft, C E., Kalagasidis, A S., Adl-Zarrabi, B., Roels, S., Carmeliet, J., Hens, H., Grunewald, J., Kunk, M., Becker, R., Shamir, D., Adan, O., Brocken, H., Kumaran, K., and Djebbar, R., “Assessment Method for Numerical Prediction Models for Combined Heat, Air and Moisture Transfer in Building Components: Benchmarks for One-dimensional Cases,” Journal of Thermal Envelope and Building Science, Vol 27, No 4, April 2004, p 307-327-352 Roels, S., “Modeling Unsaturated Moisture Transport in Heterogeneous Limestone,” Ph.D Dissertation, Leuven: K.U.Leuven, 2000 Roels, S., Elsen, J., Carmeliet, J., and Hens, H., “Pore Volume Distribution Determination of Limestone Combining Mercury Porosimetry and Micrography,” Mater Struct Vol 34, 2001, pp 76–82 Bomberg, M., Haghighat, F., Grunewald, J., and Plagge, R., “Capillary Transition Point as a Material Characteristic for HAM Models,” 4th International Conference on Indoor Air Quality, Ventilation and Energy Conservation in Buildings, Vol 2, 2002, pp 755–763 Bomberg, M., Carmeliet, J., Grunewald, J., Holm, A., Karagiozis, A., Kuenzel, H., and Roels, S., “Position Paper on Material Characterization and HAM Model Benchmarking,” Nordic Building Physics Symposium, Vol 1, 2002, pp 143– 150 Grunewald, J., Häupl, P., and Bomberg, M., “Towards an Engineering Model of Material Characteristics for Input to Ham Transport Simulations—Part 1: An Approach,” Journal of Thermal Envelope and Building Science, Vol 26, No 4, 2003, pp 343–366 Scheffler, G., Grunewald, J., and Häupl, P., “Calibration of an Engineering Model of Hygrothermal Material Characteristics,” IEA Annex41-report, Glasgow, Oct 2004 Roels, S., Carmeliet, J., Hens, H., Adan, O., Brocken, H., Cerny, R., Pavlik, Z., Hall, C., Kumaran, K., Pel, L., and Plagge, R., “Interlaboratory Comparison of Hygric Properties of Porous Building Materials,” Journal of Thermal Envelope and Building Science, Vol 27, No 4, April 2004, p 307-305325 Carmeliet, J and Roels, S., “Determination of the Moisture Capacity of Porous Building Materials,” Journal of Thermal Envelope and Building Science, Vol 25, No 3, 2002, pp 209– 237 Carmeliet, J., Gaublomme, J., and Janssen, H., “Influence of Hysteresis on the Moisture Buffering of Wood,” IEA Annex41-Report, Glasgow, Oct 2004 Descamps, F., “Continuum and Discrete Modelling of Isothermal Water and Air Transfer in Porous Media,” Ph.D Thesis, Catholic University of Leuven, Leuven, 1997 Carmeliet, J., Descamps, F., and Houvenaghel, G., “Multiscale Network Model for Simulating Liquid Water and Water CHAPTER 28 关56兴 关57兴 关58兴 关59兴 关60兴 关61兴 关62兴 关63兴 关64兴 关65兴 关66兴 Vapour Transfer Properties of Porous Materials,” Transp Porous Media, Vol 35, 1999, pp 67–88 Carmeliet, J., and Roels, S., “Determination of the Isothermal Moisture Transport Properties of Porous Building Materials,” Journal of Thermal Envelope and Building Science, 24, 2001, pp 183–210 Carmeliet, J., Hens, H., Roels, S., Adan, O., Brocken, H., Cerny, R., Pavlik, Z., Hall, C., Kumaran, K., and Pel, L., “Determination of the Liquid Water Diffusivity from Transient Moisture Transfer Experiments,” Journal of Thermal Envelope and Building Science, Vol 27, No 4, April 2004, pp 277– 305 Roels, S., Carmeliet, J., Hens, H., Adan, O., Brocken, H., Cerny, R., Pavlik, Z., Ellis, A T., Hall, C., Kumaran, K., Pel, L., and Plagge, R., “Comparison of Different Techniques to Quantify Moisture Content Profiles in Porous Building Materials,” Journal of Thermal Envelope and Building Science, Vol 27, No 4, April 2004 pp 261–276 Israelachvili, J N., Intermolecular and Surface Forces With Application to Colloidal and Biological Systems, Academic Press, London, 1985 Yates, D J C., “The Expansion of Porous Glass on the Adsorption of Non-polar Gases,” Proc Royal Soc London, Vol A224, 1954, pp 526–543 Bažant, Z P., “Constitutive Equation for Concrete Creep and Shrinkage Based on Thermodynamics of Multi-phase Systems,” Mater Struct., Vol 3, 1970, pp 3–36 Bažant, Z P., Hauggaard, A B., Baweja, S., and Ulm, F.-J., “Microprestress Solidification Theory for Concrete Creep., I Aging and Drying Effects,” J Eng Mech Vol 123, 1997, pp 1188–1194 Powers, T C., “Mechanism of Shrinkage and Reversible Creep of Hardened Cement Paste,” Proceedings, International Conference on the Structure of Concrete, Cement and Concrete Association, London, U.K., 1965, pp 319–344 Wittmann, F H., Bestimmung physikalischer Eigenschaften des Zemmentsteins Deutscher Ausschuss fur Stahlbeton, Heft 232, W Ernst & Sohn, Berlin, 1974, pp 1–63 Bear, J., and Bachmat, Y., Introduction to Modeling of Transport Phenomena in Porous Media, Kluwer Academic Publishers, Dordrecht, 1991 Carmeliet, J., “Coupling of Damage and Fluid-Solid Interactions in Quasi-brittle Nonsaturated Porous Materials,” Iutam Symposium on Theoretical and Numerical Methods in Continuum Mechanics of Porous Materials, Stuttgart, Sept 5–10, 䊏 关67兴 关68兴 关69兴 关70兴 关71兴 关72兴 关73兴 关74兴 关75兴 关76兴 关77兴 关78兴 关79兴 TOWARDS DEVELOPMENT OF METHODS 605 1999 Baggio, P., Majorana, C E., and Schrefler, B A., “Thermohygro-mechanical Analysis of Concrete” J Eng Mech Vol 126, 2000, pp 223–242 Coussy, O., Mechanics of Porous Continua, John Wiley & Sons, Chichester, 1995 Coussy, O., Eymard, R., and Lassabatère, T., “Constitutive Modelling of Unsaturated Drying Deformable Materials,” J Eng Mech 1998, pp 658–667 Grasberger, S., and Meschke, G., “Numerical Simulation of Coupled Thermo-Hygro-Mechanical Processes Within Concrete,” 6th International Conference on Creep, Shrinkage and Durability of Concrete and other Quasi-Brittle Materials 共Concreep 6兲, Cambridge, USA, 2001 Lewis, R W., and Schrefler, B A., The Finite Element Method in the Static and Dynamic Deformation and Consolidation of Porous Media, John Wiley & Sons, Chichester, 1998 Coussy, O., Ulm, F.-J., and Mainguy, M., “A Short Course on Environmental Mechanics of Concrete,” Lecture notes, Udine, 1999 Ulm, F.-J., Torrenti, J.-M., and Adenot, F., “Chemoporoplasticity of Calcium Leaching in Concrete, J Engineering Mech Vol 125, 1999, pp 1200–1211 Carmeliet, J., Delerue, J F., Vandersteen, K., and Roels, S., “Three-dimensional Liquid Transport in Concrete Cracks,” Int J Numer Analyt Meth Geomech Vol 28, 2004, pp 671– 687 Therrien, R., and Sudicky, E A., “Three-dimensional Analysis of Variably-saturated Flow and Solute Transport in Discretely-fractured Porous Media,” J Contam Hydrol Vol 23, 1996, pp 1–44 Roels, S., de Proft, K., and Carmeliet, J., “A Coupled Discrete Approach to Simulate Moisture Effects on Damage Processes in Porous Materials,” submitted for publication in Comput Methods Appl Mech Eng 2004 de Proft, K., “A Combined Experimental Computational Study to Discrete Fracture of Brittle Materials,” Ph.D Thesis, Vrije Universiteit Brussel, 2003 Roels, S., Vandersteen, K., and Carmeliet, J., “Measuring and Simulating Moisture Uptake in a Fractured Porous Medium,” Adv Water Resour Vol 26, 2003, pp 237–246 IEA-Annex 41, “Whole Building Heat, Air and Moisture Response,” International Energy Agency 共IEA兲, Energy Conservation in Buildings and Community Systems 共ECBCS兲, http:// www.kuleuven.be/bwf/projects/annex41/index.htm, 2005 MNL18-EB/Oct 2009 Subject Index A C adhered 共bonded兲 wood products, 59–61 adsorption, 2–3 adsorption isotherm, aerated concrete, 48 aerobiology, bacteria, 82 air ambient, 111 barrier systems, 18–19 barriers, high-rise, 416 distribution, 124 infiltration and ventilation, 111–116 leakage characteristics for building enclosure, assembly and materials, 19–21 air conditioning, residential buildings, 397–398 airtightness, 111 data, 113 tests, 31–32 ambient air, 111 apparent thermal conductivity, 39 architects and engineer role, quality, 496 certificates, 570–571 arthropods, 82 assemblies, 18 assumed design responsibility, 568 ASTM standard guidelines and practices, 476–477 attics condensation, 197–198 manufactured housing, 431–432 axial and radial system, wood, 54–56 B bacteria, 74, 82 aerobiology, 82 and water temperature and light, 82 barrier systems, air, 18–19 basements, 108–109 case studies, 197 wall and below grade drainage systems, 25–26 bathrooms, 105 biocides for contamination prevention, 86 biological attack, 73 Boston Cap roof, 321 Brady Array, 144 British standards, 477 building envelopes airtightness, 113 defined, 494 high-rise buildings, 401–425 quality design, 551–556 buildings airflow, 150–151 components, 238–240 enclosures, 229–242 industry challenges, quality design, 497–498 pressurization/depressurization, high-rise, 403–404 Canadian standards, 477 canopy connection to wall, 276 capacitance techniques, 146–147 capillary breaking layer, 25 capillary moisture content, 27, 34–35 capillary transport, 30–31 carbon, 144 carpenter ants, 75 case studies, 181–224 attic condensation, 197–198 basements, 197 crawl spaces, 193–196 dehumidifiers, 192–193 exterior moisture problems, 183 exterior wall moisture problems, 183, 193–215 indoor moisture problems, 181–182, 183–193 inside exterior walls, 215–219 moisture inside exterior walls, 215 mold and mildew problems, 182–183 roofing, 198–200 siding, 200–201 southern climates, 213–215 weatherization, 189–190 cathedral ceilings, 322 cell wall, lumen, moisture, wood, 56 cell-to-cell connections, wood, 56 cladding design, high-rise buildings, 409–416 climate data sheets, 91–103 new residential buildings, 343, 347–348 cockroaches, 82 codes, 486–488 cold climate issues, 124 new residential buildings, 347–348 combustion appliances, residential buildings, 398 commercial buildings, 241 concentration decay method, 151 condensation of humid air on colder surfaces, 164–166 constant concentration method, 151–152 constant injection method, 152 constant volume terminal reheat, 125 construction contract documents, 515–519 influence on process, 127–128 management firm role, 496 moisture, 104, 167 construction failure defined, 567 trail, 575–579 construction project meetings, 527–530 plan, 535–547 team, 519–527 contract documents moisture control, 464–472 using specifications in investigations, 469–470 606 Copyright © 2009 by ASTM International www.astm.org 䊏 water vapor, air, weather barriers/retarders, 471–472 writing specifications, 470–471 contractors failure, 567–568 cooling coils, 120–124 of moist air and condensation, 11–12 cork, 49 crawl spaces, 166 case studies, 193–196 residential buildings, 394–396 creep, wood, 71–72 curtain wall, 290 foundation, 291 parapet, 293–297 spandrel, 292 D deficiency/rework tracking guidelines, 558–565 dehumidifiers, 192–193 design professional failure, 569 tools, 129–138 wind pressures, 404–407 developments during last decade, 589–590 dew cell, 142 dew point hygrometers, 140–142 method, 130 dimensional changes, wood, 65–71 bonded wood products, 66–69 compression set shrinkage, 70–71 stability, 65–66 surface checking, 70 warp, 69–70 distribution, air, 124 driving forces, 112–113 driving rain, 91 dual duct, 125 duct systems, 432–433 Dunmore, 144 durability assessment, 594–598 E effects on thermal insulating materials, 38–51 electrical resistance techniques, 145–146 electrolytic hygrometer, 145 enclosures, 18 energy codes, buildings, 488 envelope water leakage, high-rise buildings, 417–420 environmental barriers and driving forces, 583 environmental loads, new residential buildings, 343 European standards, 477 evaporation from wet surfaces, 105–106 exfiltration, 111 exhaust air, 111 expanded polystyrene, 46 experience-based design, 232–238 exterior climate SUBJECT INDEX 607 data, 87–103 elements, 90–91 exterior moisture problems, 183 exterior sources, 161 exterior thermal insulation, 29 exterior wall moisture problems, 183, 193–215 extruded polystyrene, 46 F facilities contracting process, quality design, 498–503 failure to warn of known defects, 568–569 fastener performance, 72–73 fenestration, ASTM standards, 481–482 flooded basement, 108 floors ASTM standards, 485 manufactured housing, 430 fog-type dew point meter, 142 foundations new residential buildings, 360–362 residential buildings, 393–397 to wall, 251 Fourier’s law, 38–39 framed membrane roofing systems, 328–330 framed water-shedding roofing systems, 320–327 fresh air ventilation, manufactured housing, 433 fungal aerobiology, 82 fungal ecology, 81 fungi, 80 physiology, 80–81 G Glaser diagram, 133 grain angle, wood, 56–57 ground, moisture source, 109 growth rings wood, 56–57 gutters, residential buildings, 392 H heartwood, 57–58 heat transfer mechanisms, dry insulating materials, 38–39 heat, air, and moisture 共HAM兲 transport, heating and cooling equipment, 118–128 heating of moist air, 11 high-rise buildings, 378–387 air barriers, 416 building envelope, 400–425 building pressurization/depressurization, 403–404 cladding design, 409–416 design wind pressures, 404–407 envelope water leakage, 417–420 humidification/dehumidification, 403 masonry cladding, 407 mechanical equipment performance, 402–403 plaza-deck waterproofing, 420–421 precipitation, 413 608 MOISTURE CONTROL IN BUILDINGS - 2ND EDITION roof systems, 407 roofing and, 422–423 temperature, 412 ventilation, 403 wall systems, 407–409, 423–424 waterproofing and, 424–425 weather data, 414–415 wind effects, 382–387 wind forces, 413 historic buildings and preservation, 443–461 historic exteriors, 446–456 historic interiors, 456–461 moisture sources, 443–446 holistic approach to building design, 16–17 hot, humid climates, new residential buildings, 351–353 HUD regulations, manufactured housing, 435–437 human health effects, 82–86 human sources of moisture, residential buildings, 398 humid air, 109 humidification/dehumidification, high-rise buildings, 403 humidity ratio, 10–11 HVAC equipment, 124–125 hygric properties measurements, 35 hygrothermal characteristics measurement, 31–35 of materials, 16–35 hypersensitivity diseases, 82–83 I ideal gas law, 10 identification of moisture sources, 161–167 IECC climate zone map, 489 improvements, roofs, 316–317 in-plant construction environment, manufactured housing, 433–434 indoor moisture problems, 181–182, 183–193 indoor sources of moisture, 104–108 infections, 83 infiltration, 111, 112–115 air, 111–116 manufactured housing, 433 measurement, 115 insects, 75 inside exterior walls, 215–219 inspection of work, 569–570 installation on site, manufactured housing, 434–435 institutional buildings, 241 interior sources, 161 interior steam leak in historical building, 174–175 interlocked grain, 57 interzone airflows, 116 investigation checklist, 168–169 ion exchange, 144 J Jason, 144 juvenile wood, 58 䊏 K Kieper diagram, 133–134 kitchens, 105 L laboratory versus field testing, 157–158 laminated strand lumber, 59–61 leakage characteristics for building enclosure, assembly and materials air, 19–21 legal considerations, 567–579 libraries and museums, 377 limiting material performance characteristics, 585–587 liquid penetration resistance 共LPR兲 test method, 32–33 liquid transport, 6–7 loose-laid and mechanically attached membranes, 317– 318 Lyman-alpha hygrometer, 142–144 M makeup air, 111 managing quality, 508–515 manual design tools, 129–130 limitations, 134–135 manufactured housing, 429–441 attics, 431–432 duct systems, 432–433 floors, 430 fresh air ventilation, 433 HUD regulations, 435–437 in-plant construction environment, 433–434 infiltration control, 433 installation on site, 434–435 moisture dynamics, 429–434 mold, 441 recommendations, 438–440 remediation, 441 walls, 430–431 masonry cladding, high-rise buildings, 407 material characteristics airflow control, 17–18 rain and ground water control, 21–27 materials, 18 mature wood, 58 measurement basics, 153 in solid materials, 145–147 techniques and instrumentation, 140–158 mechanical, 144–145 mechanical equipment performance, high-rise buildings, 402–403 mechanical ventilation, 111, 115–116 metal roofing, 318 microbes, 73 microbial growth prevention, 84 mildew 䊏 case study, 571–574 problems, 182–183 mineral fibers, 49 mites, 82 mixed climates, new residential buildings, 348–351 modeling heat, air and moisture transport, moist material measurement, 43–44 moisture, 61–65 caused by building envelope problems, 161–179 content of air, 90 control issues, quality design, 494–495 from occupancy, 166 in service, 64–65 inside exterior walls, 215 manufactured housing, 429–434 new residential buildings, 344–347 retention curve, 30 sources, 104–110 transfer to heat transfer, 40–42 transport control, 27–31 transport equations, moisture-originated damage, 592–594 further needs, 603 recent developments, 598–603 molds, 73–74 case study, 571–574 manufactured housing, 441 new residential buildings, 343–344 problems, 182–183 multifamily housing in northwest, 173–174 multiple trace techniques, 153 multizone, 125 N natatoriums, 378 natural durability, 57–58 natural ventilation, 111, 115 need for quality design, 495 neutron thermalization methods, 147 new commercial buildings, 365–389 design, 365–368 institutional buildings, 376–377 predicting moisture performance, 368–376 new high-rise buildings, 365–389 new institutional buildings, 376–377 new residential buildings, 343–362 climate dependence, 343 cold climates, 347–348 environmental loads, 343 foundation assemblies, 360–362 hot, humid climates, 351–353 mixed climates, 349–351 moisture control practices, 344–347 roof assemblies, 359–360 surface mold, 343–344 wall assemblies, 353–359 North American industry guidelines, 478 SUBJECT INDEX O open water surface, 107 organisms, 80 organizations, for standards, 556–557 oriented strand board, 59–61 outdoor air, 111 outdoor sources, 108–109 overhang section, 275 overhanging sloped roof, 278 owner’s role, quality design, 495–496 P parapets, 241–249 to wall junction, 253–261 partnering, quality design, 498 people, moisture source, 104–105 performance analysis, 584–585 performance evaluation, design process and, 587–588 perlite, 47 phase changes, phenolic foam, 48 piezoelectric crystal, 144 plans and programs for quality control, 530–535 plants, moisture source, 105 plaza-deck waterproofing, high-rise buildings, 420–421 plumbing, residential buildings, 397 plywood, 59–61 polyurethane foam, 47 polyvinylchloride foam, 46 poor workmanship, 568 poroelasticity, 600 precipitation, high-rise buildings, 413 process-generated moisture, 128 properties of moist air, 10 psychrometric calculations, 9–10 psychrometric chart, 11–12 punch-out list, 546 punched window, 264–268, 269–275 Q qualitative leak location, 155–156 quality design architect and engineer role, 496 building envelope commissioning, 551–556 building industry challenges, 497–499 construction contract documents, 515–519 construction management firm role, 496 construction project documents, 547–551 construction project meetings, 527–530 construction project plan, 535–547 construction project team, 519–527 deficiency/rework tracking guidelines, 558–565 facilities contracting process, 498–503 in building envelope, 493–566 managing quality, 508–515 moisture control issues, 494–495 609 610 MOISTURE CONTROL IN BUILDINGS - 2ND EDITION need for, 495 owner’s role, 495–496 partnering, 498 plans and programs for quality control, 530–535 quality concepts, 503–508 subcontractors, 497 success tips, 557–558 R rain leakage, 107, 163–164 rain-soaked walls and roofs, 108 re-roofing, 330–333 wet insulation, 336–337 reaction wood, 58 recreational sports and entertainment buildings, 377–378 reheat, 122–124 system control, 128 relative humidity, 10 relative humidity measurement, 140–145 remediation manufactured housing, 441 mold, 86 residential buildings, 107–108, 390–398 air conditioning, 397–398 combustion appliances, 398 crawl spaces, 394–396 foundation, 393–397 gutters, 392 human sources of moisture, 398 plumbing, 397 roof, 390–392 slab, 396 sump pump, 397 surrounding soil, 393 ventilation, 398 walls, 392–393 water from indoors, 397–398 water from outdoors, 390–392 windows, 393 return air, 111 rising damp, 167 roofs, 313–321 and high-rise buildings, 422–423 ASTM standards, 480 case studies, 198–200 high-rise buildings, 407 new residential buildings, 359–360 residential buildings, 390–392 to wall connection, 249–250 䊏 sill, 282–284, 286–287 sill to curtainwall, 279 sill to roof, 281 slab, residential buildings, 396 sliding snow and ice, roofs, 326 sling psychrometers, 140 slope of grain, 57 sloped glazing, 275 software for heat, air, moisture 共HAM兲 transport, 135–138 sorption isotherm 共equilibrium moisture content in hygroscopic range兲, 29–30 southern climates, 213–215 spatial climate, 88–89 spiral grain, 57 stains, 74 standard practices and protocols, 177–179 steady state measurements, 43 storage of moisture and energy changes, 8–9 strength, wood, 71 structural connector, 277 structural penetrations, 275 subcontractors, quality design, 497 sump pump, residential buildings, 397 sun, 90 supply air, 111 surface condensation on windows, 12–13 surrounding soil, residential buildings, 393 system selection, 125–129 T temperature, 90 high-rise buildings, 412 terminology, moisture control, 473–476 termites, 75 tests, 168 airtightness, 31–32 thermal conductivity, 45 of wet insulating material, 42–43 techniques, 147 thermal moisture diffusivity, thermal performance of moist insulation, 49–50 thermodynamic states of moisture, 1–2 thin film polymer, 145 time scale of exterior conditions, 89–90 toxicoses, 83–84 trace gas measurement techniques, 152–153 transfer air, 111 transient heat flow measurements, 43 transport of moisture, 3–4 U S sapwood, 57–58 saturation vapor pressure, 10 siding, 200–201 simultaneous heat and mass transfer models, 39–40 skylights head at wall, 289 ridge, 288 ultrasonic techniques, 147 urea formaldehyde foam, 47 V vapor transport, 4–6 vapor traps, roofs, 315–316 variable air volume 共VAV兲 reheat, 125 䊏 ventilation, 111, 115 air, 111–116 high-rise buildings, 403 requirements, 116 residential buildings, 398 roofs, 315–316 vermiculite, 48 W walls and below grade drainage systems, 25–26 ASTM standards, 481–482 drainage systems, 24 high-rise buildings, 407–409, 423–424 manufactured housing, 430–431 new residential buildings, 353–359 residential buildings, 392–393 to window details, 252–256 to window isometric details, 263 water leakage through, 149–150 with vapor retarder, 130–131 without vapor retarder, 131–132 warm and humid climate, 169–170 water, absorption coefficient, 7–8, 26–27, 34 access limitation, 84–86 bacteria and, 82 SUBJECT INDEX leakage through walls, 149–150 residential buildings, 390–392, 397–398 water resistive barrier 共WRB兲, 22 classification, 22 performance, 22–23 testing, 32–34 water vapor permeance and permeability, 5, 28–29 transmission, 32 transmission tests, 147–149 water vapor retarder, 27–28 water-shedding roofing, 318–320 waterproofing and high-rise buildings, 424–425 weather data, high-rise buildings, 414–415 weatherization, 189–190 weeping holes and flashings, 24–25 wet basements, 166 wet insulation, 335–337 wind, 90–91 high-rise buildings, 382–387, 413 windows residential buildings, 393 surface condensation on, 12–13 wood composition materials, 60–61 decay, 74 structure, 54–58 wood-boring beetles, 75 611 Heinz R Trechsel has been consulting on moisture problems in buildings for over 25 years, has managed design contracts for the Naval Facilities Engineering Command (USN), managed the Energy Conservation research program for NBS (now the National Institute for Standards and Technology), and developed innovative building products and systems for the steel industry Trechsel is a graduate architect of the Swiss Federal Institute of Technology in Zürich and a registered architect in the State of New York As a member of ASTM since 1961 he is currently active in Committees C16 on Thermal Insulation and E06 on Performance of Buildings and has been chairman of several subcommittees He received the ASTM Award of Merit in 1986 Trechsel also is a member of the National Institute of Building Sciences (NIBS) and was chairman of its Building Enclosure Technology and Environment Council (BETEC) Trechsel has published extensively on moisture control and on energy conservation in buildings He was editor of the first edition of MNL18, Moisture Control in Buildings, published in 1994; Manual 40, Moisture Analysis and Condensation Control in Building Envelopes; Co-editor of ASTM STP 719, Building Air Change Rate and Infiltration Measurements; STP 779, Moisture Migration in Buildings; STP 904, Measured Air Leakage of Buildings; and STP 1039, Water Vapor Transmission through Building Materials and Systems (with Dr Mark Bomberg) Mark T Bomberg obtained the title of Technology Doctor at the Lund University for research on moisture transport in building materials and has been involved in the field of building physics for over 35 years (25 years at the National Research Council of Canada and 10 years in academia) Bomberg also earned Doctor of Science (Engineering) from Warsaw Technical University, Poland where he previously graduated in civil engineering He currently leads the hygrothermal program at Syracuse University, Syracuse, New York An ASTM member since 1976, he is active in Committees C16 on Thermal Insulation and E06 on Performance of Buildings, he is also the recipient of the 2009 C16 David L McElroy Award He is a co-leader in the field of heat, air and moisture in the Building Enclosure Technology and Environment Council (BETEC) at the National Institute of Building Science and one of the organizers of the BEST conferences (www.thebestconference.org) where he chairs the energy efficiency track Bomberg has more than 200 research papers and several book chapters in the area of building physics; he co-edited with Heinz Trechsel ASTM STP 1039, Water Vapor Transmission through Building Materials and Systems Worth mentioning is M.T Bomberg and J.W Lstiburek, Spray Foam in External Envelopes of Buildings, published in 1998 by Technomic Publication Corporation; the third edition was reprinted by CRC Press in 2006 www.astm.org ISBN: 978-0-8031-7004-9 Stock #: MNL18-2nd