Download or read book Evaluation of Existing Moisture Content in Brick for Hygrothermal Models in the Rehabilitation of Mass Masonry Walls written by Rex Cyphers and published by . This book was released on 2018 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: A research study was undertaken to evaluate an in situ test method for determining the existing moisture content of brick masonry for use in hygrothermal models. Currently, ASTM E3069, Standard Guide for Evaluation and Rehabilitation of Mass Masonry Walls for Changes to Thermal and Moisture Properties of the Wall [1], is one of the only industry references providing guidance for evaluating the existing moisture content of masonry materials in buildings when the addition of insulation or other changes to the wall assembly are being considered. When interior insulation or a continuous air barrier is considered for addition to mass masonry walls to meet new energy standards, understanding the properties of the brick, the condition of the wall, and the existing moisture content of the brick are imperative for evaluating the hygrothermal performance of the wall assembly. The assumptions made for the initial moisture content of materials in the hygrothermal models for a mass masonry wall can change the design and alteration approach and, in some cases, could lead to a repair that would have detrimental long-term effects. In the laboratory, the interstitial relative humidity within the brick was measured utilizing temperature and humidity probes embedded within the brick body. The moisture content of the brick was measured at various humidity levels and then compared to various published isotherm curves. In addition to the laboratory testing, field-testing was conducted at five historic buildings with mass masonry wall assemblies to assess the moisture content of the masonry utilizing the same methods as were used for the laboratory testing. When within the hygroscopic range, these methods could be used as minimally invasive and direct techniques to measure the existing moisture content of the brick to develop more accurate and situationally specific hygrothermal models when evaluating existing mass masonry walls prior to a renovation.
Download or read book Role of Initial Moisture Content on Hygrothermal Models and Envelope Performance written by Carly May Wagner and published by . This book was released on 2020 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: Countless inputs are used in transient hygrothermal analysis, just as countless variables determine the long-term hygrothermal performance of a real-world building envelope assembly. One variable often overlooked, oversimplified, and inaccurately accounted for is the initial moisture content of materials. This paper discusses the impact initial moisture content has on both the real-world performance and the accuracy of the modeled hygrothermal performance. ASHRAE Standard 160, Criteria for Moisture-Control Design Analysis in Buildings , provides guidelines for assumptions of initial moisture content inputs in hygrothermal analysis. These guidelines are generic in nature and are not necessarily representative of in-service conditions. The authors conducted a study to explore the role that a range of inputs have on the accuracy of hygrothermal models. Temperature and humidity data across a wall assembly along with all necessary interior and exterior climate data were collected over the course of several seasons. The data were used to develop a series of WUFI models, attempting to validate these models and the default or recommended inputs. The study indicated that the models did not accurately reflect the data recorded in the field unless values for the initial moisture content matched what was recorded in the field rather than the default ASHRAE 160 recommended values. This study, and several other real-world cases where excessive initial moisture content has led to envelope failures, highlights the importance of accurately accounting for initial moisture content. Particularly in the cases of renovations and restoration projects, methods are available to determine realistic values of the initial moisture content within the existing materials. Appropriate methods for determining the initial moisture content of materials comprising existing envelope assemblies are discussed, including the methods contained within the new standard ASTM E3069-19, Standard Guide for Evaluation and Rehabilitation of Mass Masonry Walls for Changes to Thermal and Moisture Properties of the Wall.
Download or read book Masonry 2018 written by Norbert V. Krogstad and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Evaluation of Existing Moisture Content of Brick for Hygrothermal Models in the Rehabilitation of Mass Masonry Walls / R. and A. Cyphers, J. Knorowski, and A. Skertic -- Proposal for an Improved Procedure and Interpretation of ASTM C1531 for the In-situ Determination of Brick-Masonry Shear Strength / F. Graziotti, G. Guerrini, A. Rossi, G. Andreotti, and G. Magenes -- Ambient Vibration of Unreinforced Masonry Buildings in Dhaka City / M. Khan, A. Fahim, R. Ahsan -- Sustainable Cellulose Masonry / Z. Olson, W. Cook, and D. Henneke -- Dynamic Thermal Performance Measurements of Residential Wall Systems / J.P. Sanders and N. Huygen -- Thermal Property Measurement of Non-Homogeneous Masonry Materials / J.P. Sanders, N. Huygen, and S. Smith -- Brick Masonry: Crisis in Aesthetics? / I. R. Chin, Wiss, Janney -- The Evolution of Stone Masonry Veneer Requirements - Past, Present, and Future / J. Civitillo and E. Peterson -- Shear Strength of FRP-Reinforced Concrete Masonry Beams / S. Sarhat and E. Sherwood -- History of Cold-Formed Steel Framing Used as a Backing for Brick Veneer / Charles Clark Jr., Cortney Fried, Jim Bryja -- Addressing Maximum Design Deflection Recommendation for Cold-Formed Steel Framing When Used as a Backing for Brick Veneer-Review of Literature / C. Clark, Jr., C. Friend and J. Bryja.
Download or read book Moisture Problems in Historic Masonry Walls written by Baird M. Smith and published by . This book was released on 1984 with total page 52 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of Joist Masonry Moisture Content Monitoring written by and published by . This book was released on 2015 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are many existing buildings with load-bearing mass masonry walls, whose energy performance could be improved with the retrofit of insulation. However, adding insulation to the interior side of walls of such masonry buildings in cold (and wet) climates may cause performance and durability problems. Some concerns, such as condensation and freeze-thaw have known solutions. But wood members embedded in the masonry structure will be colder (and potentially wetter) after an interior insulation retrofit. Moisture content & relative humidity were monitored at joist ends in historic mass brick masonry walls retrofitted with interior insulation in a cold climate (Zone 5A); data were collected from 2012-2015. Eleven joist ends were monitored in all four orientations. One limitation of these results is that the renovation is still ongoing, with limited wintertime construction heating and no permanent occupancy to date. Measurements show that many joists ends remain at high moisture contents, especially at north- and east-facing orientations, with constant 100% RH conditions at the worst cases. These high moisture levels are not conducive for wood durability, but no evidence for actual structural damage has been observed. Insulated vs. non-insulated joist pockets do not show large differences. South facing joists have safe (10-15%) moisture contents. Given the uncertainty pointed out by research, definitive guidance on the vulnerability of embedded wood members is difficult to formulate. In high-risk situations, or when a very conservative approach is warranted, the embedded wood member condition can be eliminated entirely, supporting the joist ends outside of the masonry pocket.
Download or read book Standard Guide for Evaluation and Rehabilitation of Mass Masonry Walls for Changes to Thermal and Moisture Properties of the Wall written by and published by . This book was released on with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Hygrothermal Numerical Simulation Tools Applied to Building Physics written by João M.P.Q. Delgado and published by Springer Science & Business Media. This book was released on 2012-12-15 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a critical review on the development and application of hygrothermal analysis methods to simulate the coupled transport processes of Heat, Air, and Moisture (HAM) transfer for one or multidimensional cases. During the past few decades there has been relevant development in this field of study and an increase in the professional use of tools that simulate some of the physical phenomena that are involved in Heat, Air and Moisture conditions in building components or elements. Although there is a significant amount of hygrothermal models referred in the literature, the vast majority of them are not easily available to the public outside the institutions where they were developed, which restricts the analysis of this book to only 14 hygrothermal modelling tools. The special features of this book are (a) a state-of-the-art of numerical simulation tools applied to building physics, (b) the boundary conditions importance, (c) the material properties, namely, experimental methods for the measurement of relevant transport properties, and (d) the numerical investigation and application The main benefit of the book is that it discusses all the topics related to numerical simulation tools in building components (including state-of-the-art and applications) and presents some of the most important theoretical and numerical developments in building physics, providing a self-contained major reference that is appealing to both the scientists and the engineers. At the same time, this book will be going to the encounter of a variety of scientific and engineering disciplines, such as civil and mechanical engineering, architecture, etc... The book is divided in several chapters that intend to be a resume of the current state of knowledge for benefit of professional colleagues.
Download or read book Interface Influence on Moisture Transport in Building Components written by João M. P. Q. Delgado and published by Springer Nature. This book was released on 2019-09-10 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: The knowledge of moisture migration inside building materials and construction building components is decisive for the way they behave when in use. The durability, waterproofing, degrading aspect and thermal behaviour of these materials are strongly influenced by the existence of moisture within their interior, which provoke changes in their normal performance, something that is normally hard to predict. Due to the awareness of this problem, the scientific community have per-formed various studies about the existence of moisture inside porous materials. The complex aspects of moisture migration phenomenon tended to encompass monolithic building elements, since the existence of joints or layers contributes to the change of moisture transfer along the respective building element that contribute to the change of mass transfer law. The presentation of an experimental analyses concerning moisture transfer in the interface of material that makes up masonry is described in such a way as to evaluate the durability and/or avoid building damages. In this work it was analysed, during the wetting process, the influence of different types of interface, commonly observed in masonry, such as: perfect con-tact, joints of cement mortar, lime mortar, and the air space interface. The results allow the calculation of the hygric resistance. With these results, it is possible to use any advanced hygrothermal simulation program to study the water transport in building elements, considering different interfaces and their hygric resistance.
Download or read book Water Problems in Building Exterior Walls written by Jon M. Boyd and published by ASTM International. This book was released on 1999 with total page 335 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Moisture Resistance of Brick Masonry Walls Condensation Analysis written by Brick Institute of America and published by . This book was released on 1993 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Whole Building Heat and Moisture Analysis written by Fitsum Tariku and published by . This book was released on 2008 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Evaluation of the Potential for Corrosion Mold Growth and Moisture Accumulation Within Typical Brick Veneer Wall Assemblies Designed Per 2006 International Energy Code in a Mixed Humid Climate written by Rhett A. Whitlock and published by . This book was released on 2014 with total page 67 pages. Available in PDF, EPUB and Kindle. Book excerpt: With respect to the prescriptive minimum insulation requirements and the mandatory interior vapor retarder requirements for building envelopes in Climate Zone 4A, there are major changes included in the 2009 International Energy Conservation Code (IECC) relative to the 2006 IECC that help reduce the potential for moisture accumulation within the stud cavity. The bidirectional drying potential of walls constructed in mixed-humid climates is typically critical for preventing moisture accumulation within exterior walls. The 2006 IECC includes mandatory requirements for a vapor retarder installed on the warm-in-the-winter side of the insulation in Climate Zones 4 to 8. The climate in Zone 4A is considered mixed humid and varies greatly from the other northern climate zones. Hygrothermal models show that interior vapor retarders can create the potential for condensation and moisture accumulation related to issues within the interior portions of the stud cavity during cooling seasons in Zone 4A climates, because the vapor retarder restricts drying to the interior. This vapor retarder requirement was removed from the 2009 IECC. The 2006 IECC includes prescriptive requirements for the minimum insulation within light-gauge steel stud walls but does not require any continuous insulation within the exterior air cavity; this is required by the 2009 IECC. Hygrothermal modeling shows that when the interior vapor retarder is omitted, the continuous insulation within the exterior air cavity becomes important in mixed-humid climate zones during the heating season, when building envelopes dry to the exterior. The continuous insulation shifts the thermal gradient and location of the dew point temperature exterior of the stud cavity where condensation can be properly managed. This paper compares results of a field study to results of hygrothermal models to evaluate the potential for moisture accumulation, corrosion, and mold growth within a wall designed per the 2006 IECC. This comparison of the field results to the modeling is also used to assess the general effectiveness and overall accuracy of the tools commonly used by designers to predict moisture accumulation in wall assemblies. An eight-month-long field study of the hygrothermal behavior of a typical wall assembly designed in accordance with the 2006 IECC was conducted. The wall assembly consisted of brick veneer, exterior air space, exterior water-resistive barrier, exterior sheathing, foil-faced batt insulation in a 6-in. steel stud cavity, and interior gypsum board. Data loggers were used to record the temperature and relative humidity at several locations within the wall assembly. The field measurements were compared to transient hygrothermal models of this wall assembly. The modeling was conducted in general accordance with ASHRAE 160 using WUFI Pro 5.1. When the simulations were performed to account for the interior and exterior ambient conditions and the initial material moisture contents recorded during the field study, the simulation closely matched the collected data. This provides validation of the methodology and calculations used in the simulation. However, it also highlights the need for accurate assumptions regarding the climates to which the building assembly will be subjected, as well as accurate assumptions regarding the initial moisture contents of materials, particularly when the assembly includes a vapor retarder.
Download or read book A Test Method to Identify the Onset of Freeze Thaw Deterioration in Masonry written by John Straube and published by . This book was released on 2014 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Our aging building stock provides tremendous opportunities to reduce our overall environmental footprint through upgrades to the exterior enclosure. It is often preferable to modify existing building enclosures rather than to replace them. Buildings with solid or load-bearing masonry walls typically employ interior insulation retrofit strategies as these buildings often have heritage significance that preclude work from the exterior. Adding insulation on the interior side of solid masonry walls may result in accelerated masonry freeze-thaw deterioration, embedded metal (lateral ties and supporting angles/structure) corrosion, and/or embedded wood joist rot. A limit states design approach is used extensively when designing structures but is still in its infancy for designing building enclosures. In general, limit states design consists of identifying material failure types and then making design decisions so that the probability of reaching the associated limit state is below a prescribed value. In masonry walls, the types of durability failure include freeze-thaw (or frost) damage, salt deterioration, corrosion of embedded metals, and wood rot. With respect to frost damage, the proposed pertinent material property limit is the Critical Degree of Saturation (Scrit) defined as the minimum moisture content of a brick unit at which internal damage may occur if the unit is subject to freeze-thaw cycling. This paper describes a method for determining the Scrit in brick masonry units using frost dilatometry. The process involves wetting specimens to various degrees of saturation, sealed in a manner to limit moisture loss, and then subjecting them to multiple freeze-thaw cycles. The change in length of the specimens following freeze-thaw testing is measured, expressed in terms of microstrain, and plotted against degree of saturation. Scrit is the lowest degree of saturation at which microstrain is greater than measurement error. Two methods may be used to identify if a material may exceed Scrit in service: hygrothermal modeling and maximum saturation coefficient. Hygrothermal modeling is a comparative approach suited for analyzing the change in frost damage risk when insulating existing historic masonry buildings. Maximum saturation coefficient is an expedient but conservative method that is most useful in assessing whether new brick should be used in severe weathering applications. Moving towards a limit states approach in assessing masonry durability has proven useful in practice for assessing whether a specific masonry unit type can safely be used in a severe weathering application and assessing materials and methods of insulating historic masonry buildings without unacceptably increasing the risk of frost damage.
Download or read book Hygrothermal Performance of Building Components and Building Elements Assessment of Moisture Transfer by Numerical Simulation written by British Standards Institute Staff and published by . This book was released on 2007-08-31 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Construction systems parts, Construction materials, Moisture, Moisture measurement, Water absorption, Water vapour, Condensation, Humidity, Rainfall, Heat transfer, Drying, Mathematical calculations, Simulation, Thermal design of buildings
Download or read book Moisture Penetration of Brick Masonry Walls written by Walter C. Voss and published by . This book was released on 1932 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Damp Indoor Spaces and Health written by Institute of Medicine and published by National Academies Press. This book was released on 2004-10-01 with total page 369 pages. Available in PDF, EPUB and Kindle. Book excerpt: Almost all homes, apartments, and commercial buildings will experience leaks, flooding, or other forms of excessive indoor dampness at some point. Not only is excessive dampness a health problem by itself, it also contributes to several other potentially problematic types of situations. Molds and other microbial agents favor damp indoor environments, and excess moisture may initiate the release of chemical emissions from damaged building materials and furnishings. This new book from the Institute of Medicine examines the health impact of exposures resulting from damp indoor environments and offers recommendations for public health interventions. Damp Indoor Spaces and Health covers a broad range of topics. The book not only examines the relationship between damp or moldy indoor environments and adverse health outcomes but also discusses how and where buildings get wet, how dampness influences microbial growth and chemical emissions, ways to prevent and remediate dampness, and elements of a public health response to the issues. A comprehensive literature review finds sufficient evidence of an association between damp indoor environments and some upper respiratory tract symptoms, coughing, wheezing, and asthma symptoms in sensitized persons. This important book will be of interest to a wide-ranging audience of science, health, engineering, and building professionals, government officials, and members of the public.
Download or read book High Performance Enclosures written by John Frederick Straube and published by . This book was released on 2012-01-30 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt: high Performance Enclosures : Design Guide for Institutional, Commercial and Industrial Buildings in Cold Climates provides guidance for architects and building enclosure engineers working to meet the growing need for buildings that have significantly lower operational energy consumption. John Straube addresses a range of practical questions about low energy building enclosures that save energy while simultaneously improving durability, comfort, and rain control: How much of an impact can the enclosure, massing, and orientation have? How much glazing is appropriate and what options are available? How much does thermal bridging matter and how can it be minimized at difficult structural details? How does one detail thick layers of continuous insulation outside of steel stud walls? Can layers of insulating sheathing reduce the risk of moisture damage?--COVER.
