Insulation Value Optimization for Low-Slope Roofs
Friday, November 16, 8:30 a.m.
Low-slope roofing assemblies include a wide range of insulation and single-ply membrane attachment methods. Often ignored is the effect of fasteners on the overall R-value of the system. This presentation will discuss R-value differences based on fastener densities and their location within the system. The analysis shows the often-significant reduction in R-value due to thermal short-circuiting and the economic cost of that due to unrealized R-value. This economic cost is contrasted with the costs of fasteners and adhesives for a range of possible attachment scenarios. Finally, the cost of reduced energy efficiency for a number of different locations is factored into the analysis. The study shows that when the costs of long-term energy efficiency and lost R-value are included into the cost/benefit analysis of various roofing assemblies, then simple mechanical attachment is not necessarily the lowest-cost long-term approach. The study has implications for future codes development because insulation is often considered to be continuous. However, this study suggests that there can be a significant difference between a designed insulation value and the effective value due to attachment method.
GAF, Parsippany, NJ
Tom Taylor is the executive director, Building & Roofing Science, for GAF. This position is focused on the relationships between individual roofing materials and the overall roof system and building envelope performance. Dr. Taylor is a frequent presenter at both national and regional industry meetings. He has over 20 years’ experience in the building products industry, all working for manufacturing organizations in a variety of new product development roles. He received his PhD in chemistry and holds approximately 35 patents.
Nonpresenting coauthors: James Kirby and James Willits
“By Others”: Transitions Between Enclosure Systems
Friday, November 16, 9:30 a.m.
Buildings rely on many different systems and materials to provide a continuous enclosure, including roofing, cladding, windows, and below-grade waterproofing. Individually, enclosure systems are generally well understood. However, transitions between two or more systems are less straightforward. Transition details are unique to each project. The design often includes some transition concepts, but may not consider constructability issues such as sequencing. Construction often includes carefully detailed system shop drawings that lack details of adjacent systems manufactured and installed “by others.” Construction has added challenges, including tolerances and sequencing. Ultimately, many transition details are left to the discretion and experience of the installers.
The design and construction of reliable transition details requires an understanding of enclosure concepts and careful coordination among all involved parties. Coordinated details must consider enclosure continuity, compatibility between materials, constructability, warranty implications, installation sequence, and other issues.
The authors will discuss continuity of the building enclosure and present strategies for designing and constructing coordinated transition details based on their combined experience. Topics will include material selection and compatibility, constructability review, coordination among trades, and addressing the inevitable challenges of construction. They will discuss several case studies to illustrate successful development of difficult transition details.
Simpson Gumpertz & Heger, Washington, DC
Nicholas Piteo is a senior project manager in the Building Technology division of Simpson Gumpertz & Heger’s Washington, DC office. He has experience in both building technology and structural projects. His experience includes investigation of existing structures and building enclosures, rehabilitation design, and new design encompassing a variety of materials and systems, including below-grade waterproofing, windows, curtainwalls, metals, sealants, masonry, wood, stone, concrete, and other materials related to building envelope construction. Piteo spends the majority of his work life analyzing issues with the building enclosure and developing solutions as part of new design consulting and investigation.Emily Wychock
Simpson Gumpertz & Heger, Washington, DC
Emily Wychock is Senior Staff I in the Building Technology division of Simpson Gumpertz & Heger’s Washington DC office. She works on projects involving new design, field investigation work, and repairs to building enclosure systems. She has consulted with architects, contractors, and building owners on commercial and residential buildings.
Quantifying Hidden Value with the Building Enclosure Performance Metric
Friday, November 16, 11 a.m.
Oak Ridge National Laboratory is developing a building enclosure performance (BEP) metric to present the overall value of a building’s enclosure system. The intent behind the research is to help building owners quantifiably justify investment in advanced envelope technologies with a metric that measures aesthetic value, structural durability, thermal comfort, and moisture resilience. The BEP metric seeks to combine positive aspects of simulations and post-construction performance measurements, such as energy use intensity (EUI) as provided by energy management information systems (EMIS). In all, there are five major categories that have a significant role in overall building enclosure energy losses: thermal resistance, installation quality, air infiltration, indoor climate, and weather conditions.
The proposed BEP metric allows for evaluation of the building energy performance, which is similar to R-value and EUI. Additionally, the BEP metric is specifically designed to account for all the aspects that involve overall building energy losses, including air infiltration. Lastly, the BEP metric goes further to account for workmanship quality and imperfections of the building thermal resistance due to penetrations and other installations. This presentation will describe how the BEP metric can be applied to various buildings and next steps with field validations.
Oak Ridge National Laboratory, Oak Ridge, TN
Dr. Pallin has worked in the building industry since 2006, and spent several years conducting research in Europe. He joined the Building Envelope Systems Research team at Oak Ridge National Laboratory (ORNL) in 2013. Dr. Pallin serves as a risk assessment moisture simulation expert, and works with both existing simulation tools and creates new tools to estimate the hygrothermal (heat and moisture) performance of building elements such as walls and roofs.
Nonpresenting coauthors: Mahabir Bhandari and Melissa Lapsa
Plaza Deck Waterproofing Design Approaches:
From Traditional to Modern
Friday, November 16, 1:30 p.m.
Plaza deck design has evolved over time when it comes to overall concept and performance. Many issues have arisen with the use of vintage plaza waterproofing systems that have had adverse effects on the durability and lifespan of buildings, structures, and the assembly itself. Common downfalls of plaza deck systems are poor overall design and construction, as well as unsatisfactory loading capacity.
The presenter will illustrate examples of experience with a variety of plazas, from turn-of-the-century traditional to modern-day. With the knowledge of traditional and modern paving materials and waterproofing systems, the criteria for successful plaza design continues to transform and confront pressing concerns of sustainability and performance. The preservation of character-defining features is always an overarching consideration. The presentation will discuss the evolution of approaches to waterproofing, from the historic plaza at Station Square in Forest Hills, Queens, to a contemporary plaza design at The Citicorp Tower in New York City. For both projects, the use of new detailing and new materials for the concealed portions of the system enabled the team to achieve a durable plaza while preserving the original design intent.
Thornton Tomasetti, Inc., New York, NY
Charu Chaudhry has over 15 years of experience in historical preservation, building envelope, roofing, and waterproofing systems. She is an associate in the Renewal Group at Thornton Tomasetti, Inc., and her work includes investigating, designing repairs, and preservation treatments for historical landmarks and sites. She has written several peer-reviewed papers and lectured extensively on the subjects of masonry, terracotta, concrete, grouting, climate change, and earth constructions. She has a bachelor of architecture degree from India, and a master’s of science in historical preservation from the University of Pennsylvania.
Moisture Accumulation in Exposed Extruded Polystyrene Insulation in Western Canada
Friday, November 16, 2:30 p.m.
Extruded polystyrene (XPS) insulation has been installed in protected membrane roof (PMR) assemblies for more than 40 years. The benefits of the PMR assembly include a continuous insulation layer and protection of the waterproofing membrane from thermal cycling; however, the insulation must meet the durability requirements of being exposed to environmental conditions. In data obtained from PMRs across western and central Canada, XPS samples were found to have ranges of water accumulation from low to high moisture contents after a range of years in service. The data include wet and dry densities, as well as the measured heat transfer coefficients of samples obtained from existing PMR assemblies. The data indicate that closed-cell insulations such as XPS in plaza, parkade, and roofing PMRs may absorb moisture over their service lives and, in some cases, compromise the energy performance of the assembly. As determined in previous studies, the effects of moisture accumulation in insulation include a reduced thermal resistance and an increased load on the structure. This data will begin to provide some correlations between PMR assemblies that result in moisture accumulation and PMRs that retain low moisture contents over their service lives.
Read Jones Christoffersen (RJC), Vancouver, BC
Colin Tougas is a student at the British Columbia Institute of Technology (BCIT) in the Building Science Masters of Engineering program under the supervision of Dr. Fitsum Tariku. Since early 2014, he’s also been a full-time employee/design engineer at RJC, conducting research under the professional guidance of Dr. Leslie Peer. While his number of years’ experience in building science is limited, he has spent many hours designing and reviewing roof-replacement projects in and around greater Vancouver.
Nonpresenting coauthors: Leslie Peer and Fitsum Tariku
Retrofitting Mass Masonry Walls From the Inside Out: Monitoring Performance
Friday, November 16, 4 p.m.
Interior renovations to existing buildings can affect the performance of the exterior envelope. The speakers will present a case study to illustrate considerations for interior retrofits to exterior mass masonry walls, and instances where long-term monitoring may be a useful component of a QA/QC program.
The envelope of the subject building originally consisted of an exterior wythe of stone with an interior wythe of clay tile and plaster. As part of an interior renovation project, the plaster and clay tile were removed, and metal studs and drywall were installed. After demolition, water infiltration was observed on the inside face of the stone. Masonry repairs were recommended to reduce infiltration, and an “interior water management strategy” was recommended to manage water that may continue to reach the interior.
To assess the hygrothermal and water-management performance of the modified exterior walls, moisture, temperature, and humidity monitors were installed within the cavity between the new interior drywall and the exterior masonry. Measurements were recorded for one year and correlated with weather data.
The speakers will present their findings as a basis for recommendations regarding the coordination of interior renovations at exterior walls, and suggestions for how and when long-term monitoring may be appropriate.
Wiss, Janney, Elstner Associates, Inc., Chicago, IL
Edward Gerns is principal with the Chicago office of Wiss, Janney, Elstner Associates, Inc. and has extensive experience related to the investigation and repair of existing buildings. He has performed evaluations of historical and modern masonry façades and overseen preparation of documents for the repair of numerous masonry-clad buildings.
Sarah Van Domelen, PE
Wiss, Janney, Elstner Associates, Inc., Chicago, IL
Sarah Van Domelen is a senior associate with Wiss, Janney, Elstner Associates, Inc. She has completed numerous investigations, including façade inspections, condition surveys, and water leakage testing. She has made repair recommendations and developed restoration details for various types of construction, including steel, concrete, and masonry. Notable projects include the American Museum of Natural History, the New York Life Insurance Building, Second Presbyterian Church of Chicago, and the Old Chicago Main Post Office. She serves on the Preservation Engineering Technical Committee of the Association for Preservation Technology International (APTi), and is a member of the Student Design-Build Competition task force.
Specification Strategies for Field Testing Success
Saturday, November 17, 8:15 a.m.
The in-situ performance of building enclosures can remain inferior to specified criteria due to a variety of factors. Although project documents often clearly define performance requirements for individual building enclosure components and systems, field-quality-control testing provisions are often underdeveloped. Since each section of specification documents is typically written individually based on a finished work product, and specified materials may be covered in multiple sections, the difficult building enclosure details are not always effectively addressed during the design phase. These inadequacies represent missed opportunities when considering the need for high-performance buildings that will function to the satisfaction of building owners and end users.
This session will include a summary of both common and more obscure exterior wall field-quality-control tests associated with air and weather barriers, claddings, windows, doors, curtainwalls, and sealants. Simply specifying a test standard is likely insufficient for achieving the intended building enclosure performance. As such, opportunities exist to improve field-quality-control testing processes and procedures by means of developing project-specific testing matrices with input from building owners, designers, specifiers, consultants, manufacturers, and contractors. Lessons learned from a variety of projects will also be presented.
Raths, Raths & Johnson, Inc., Willowbrook, IL
Jacob Arnold’s experience at Raths, Raths & Johnson, Inc. (RRJ) includes laboratory testing of building materials, in-situ quality control field testing, and development of monitoring programs to investigate the effects of environmental conditions and the performance of building components. He manages the day-to-day operations of RRJ’s laboratory and is responsible for test-program design, equipment calibration, and data recording instrumentation. He is certified as a Construction Documents Technologist (CDT) through the Constructions Specifications Institute (CSI) and is a member of ASTM International Committee D01 on Paint and Related Coatings, Materials, and Applications.
Patrick Reicher, REWC, REWO, SE, CCS, CCCA
Raths, Raths & Johnson, Inc., Willowbrook, IL
Patrick Reicher is an associate principal with Raths, Raths & Johnson, Inc. He is a licensed structural engineer in the state of Illinois with over 13 years of experience in forensic investigation, evaluation, repair design, and new construction consulting for buildings and enclosures. He is a Registered Exterior Wall Consultant (REWC), Registered Exterior Wall Observer (REWO), Certified Construction Specifier (CCS), and Certified Construction Contract Administrator (CCCA). He currently serves on RCI’s REWO Exam Development Subcommittee, on the Manual of Practice Update Task Force, and as the treasurer of the Chicago Area Chapter of RCI (CAC-RCI). He also serves on several committees and task forces as a professional member of the American Architectural Manufacturers Association (AAMA).
Where Has All The Asphalt Gone?
Saturday, November 17, 9:15 a.m.
Since the 1860s, asphalt and coal tar have been key elements in multi-ply, low-slope roof assemblies. The materials are both adhesives and waterproofing agents. They are used to form the plies and the membranes, as well as to bond the components and enhance the waterproofing quality of the multi-ply system.
Over the years, asphalt has been refined and graded to better suit applications in various regions and roof slopes. It has been modified with polymers, waxes, and additives to form membranes used in single- and multi-ply applications. Asphalt has also been modified for use solely as an adhesive to apply both built-up and single-ply systems, with no contribution to the waterproofing qualities of the roof assemblies.
Beginning in the 1970s, concerns were voiced over the use of asphalt (primarily due to health and safety—specifically odor and fire/burn issues), resulting in product evaluation by industry, government, and unions. This scrutiny ran parallel with the rise of the single-ply industry, which rarely used asphalt in assemblies.
The rise in the market share of thermoplastic polyolefin (TPO), and the marketing of TPO by major built-up manufacturers, further depressed the use of asphalt. The development and promotion of low-rise polyurethane foams used as a substitute for asphalt products also impacted the use of asphalt.
While the asphalt industry made strides in kettle technology, the methods of delivery and application have remained relatively constant and cost-effective, and yet its use remains in decline.
Does asphalt have a role in the industry today, or has it been overtaken by technology, making it no longer relevant, similar to the evolution of reinforcement from cellulose to asbestos to fiberglass?
This presentation will trace the history of the product in the industry, review the enhancements and changes that are relevant today, and look at the strides made by the asphalt industry to maintain a role in the application side of the industry.
Trinity | ERD, Seattle, WA
Darbi Krumpos has over 20 years of experience at Trinity | ERD. Initially working to support Colin Murphy in project management and coordination, her experience with the firm is quite extensive. She has worked with product manufacturers regarding code compliance and warranty support, coordinated projects worldwide, worked directly with condominium associations and owners through litigation and remediation, investigated and researched construction deficiencies and litigation, written specifications, and performed contract administration for new construction and remediation for both commercial and residential projects. She also has experience in building envelope commissioning, field testing and quality assurance, and quality control program management. With strengths in communication and organization, she has assisted in projects within all aspects of the work Trinity | ERD performs, and has a vast knowledge of the history of Trinity | ERD.
Colin Murphy, FRCI, RRC
Trinity | ERD, Seattle, WA
Colin Murphy is the principal of Trinity | ERD, which he founded in 1986. His education is in law (Scotland) and mechanical engineering. He is an author, educator, and inventor. He is a Registered Roof Consultant with numerous certifications and registrations within the building envelope discipline. Murphy has authored and presented many papers on roofing and building envelope subjects throughout the United States and Canada. He has received awards for outstanding publications and service to industry organizations. He holds 15 United States and European patents for roofing and building envelope components and systems. Murphy’s work within the firm includes forensic analysis of building envelopes, design of building envelope systems, and the testing of building envelope components and systems.
Adhesion of Air and Water-Resistive Barrier Materials: A Sticky Subject
Saturday, November 17, 10:45 a.m.
Many air- and water-resistive barriers are adhesively installed on substrates. Organizations have required a minimum value when conducting on-site pull testing. Many question the number and wonder where it comes from. There is a lot of discussion on what the loads are for a location and height of a building. Others say that the value has to do with proper installation of the materials. This presentation will cover the origins of the minimum value that is currently being used, how this value relates to installed properties, and what the purpose is of the minimum value. The presentation will also provide the results of a research project that was done to see what actual site values of pull adhesion are based on material, substrate, and other conditions.
Air Barrier Association of America, Walpole, MA
Laverne Dalgleish is the executive director of the Air Barrier Association of America (ABAA). As such, he works to champion energy conservation in buildings while educating the building owners and designers about the benefits of energy conservation such as durability, comfort, reduced maintenance, reduced HVAC equipment costs, and the positive impact on the environment. Dalgleish travels North America on a weekly basis to educate building owners and designers on the benefits of effective and working air barrier systems in buildings. This education mission includes working with standards development organizations, training and education groups, government policy departments, and quality assurance program developers for the construction industry. He is the secretariat of two ISO committees: ISO TC61 SC10, Cellular Plastics and ISO TC163 SC3, Thermal Insulation Products. He is also chair of the ULC Thermal Performance task force of the Building Environment Standards Committee.
Dalgleish was the key developer of the ABAA Quality Assurance Program for the installation of air barrier systems in buildings. This program is based on ISO 9000 and ISO 12576-2, but brings the ISO requirements together with practical applications for the air barrier industry.
Modular Construction: Should We Pre-Install Waterproofing Systems?
Saturday, November 17, 1:15 p.m.
Modular construction is a fast and rising trend in the building industry. Prefabricated units or recycled shipping containers are stacked together to create a multiplex. The various delivery methods for these types of projects ask for pre-installed waterproofing and building envelope membrane systems, which require some level of finishing in the field. Consultants are challenged with alternative design processes, product approvals, and construction sequencing, which are committed to an expedited schedule.
There is an urgent need to evaluate the pros and cons of pre-installed waterproofing systems in the context of quality-control measures for modular construction. Walls, windows, and roofing assemblies are components of the conventional building envelope in which consultants are used to designing and detailing flashing for on paper. When these systems are selected for modular construction, the manufacturing team decides and designates the best practices for the waterproofing assemblies. How are design decisions made, and are the correct performance criteria being reviewed? Who will ultimately be responsible if waterproofing issues arise in the future?
The consultant’s role as an on-call advisor becomes essential in a modular design and prefabricated project setup. Lessons learned from Walker Consultants in modular-unit construction will be shared and discussed, with ideas to improve our building envelope and waterproofing approach to this type of work.
Walker Consultants, San Francisco, CA
Annie Lo is the director of building envelope and forensic restoration for Walker Consultants in San Francisco, CA. She is a building envelope expert and a licensed architect who specializes in the design of exterior enclosures and waterproofing systems, as well as the restoration of existing buildings. Lo leads Walker’s team in the investigation of building envelope failures and consults on new construction assemblies related to below-grade waterproofing, plaza decks, exterior walls, fenestration systems, and roofing assemblies. She is a LEED Accredited Professional and a graduate of Columbia University in New York.
Mid-Rise Wood-Frame Construction: A Call for Best Practices
Saturday, November 17, 2:15 p.m.
Over the past several years, the speaker has observed an increasing number of water intrusion claims in relatively new mid-rise wood-frame buildings. While the code requires the building envelope to provide protection from the weather, it does not provide the details necessary for designers and/or contractors to meet this requirement. More specifically, vertical and lateral movements caused by frame compression, shrinkage, external loads, and material incompatibility can compromise the function of flashing, drainage, and waterproofing details. Differential movements between wood framing and exterior cladding components can cause physical damages to building envelope components that increase the extent of water intrusion. Once the water reaches the wood framing components, significant damages, such as decay, corrosion, and mold can result. Additionally, once compromised, the effectiveness of products used to meet fire resistance requirements is unknown.
Construction Science & Engineering, Inc., Westminster, SC
Derek A. Hodgin holds a bachelor of science degree in civil engineering from North Carolina State University. He has over 25 years of experience as an engineering consultant and is responsible for facility condition inspections, failure analysis, damage assessments, and forensic engineering investigations of all types of structures. His experience includes failure analysis of a wide variety of building envelope and roof systems. A large part of Hodgin’s projects have included analysis of deficient construction cases, including roofs, exterior walls, windows, doors, structural framing, civil site work, and building code review. He has performed engineering assessments of hurricane, flood, tornado, hail, wind, ice, and fire-related damages for a wide variety of commercial and residential structures in the United States and the Caribbean.
Can a Poor Air Seal Cause Roof Failure?
Saturday, November 17, 3:45 p.m.
A hospital owner in the mid-Atlantic region experienced complete roof failure within five years of installation. Components within the roofing assembly had debonded, warped, twisted, cupped, and distorted, causing the roof to no longer drain properly, and left the owner fearful that large portions of the roof would fail and blow off in a storm event.
During the course of the evaluation, thermography, roof cores, moisture meters, document review, and visual inspection techniques were used to demonstrate a number of defects in not only the design of the building but in the installation of various roofing components.
The installing contractor claimed that the building’s mechanical system was solely responsible for pressurizing and damaging the roofing materials to the point of failure. The owner claimed that there must have been a number of defects in the installation of the roofing system that caused the system failure.
During the course of the forensic evaluation, it was demonstrated that the mechanical system was not responsible for the failure of the roofing system; however, it was determined that defects in the design and construction of other building components, such as the structural steel heliport, the roofing air/vapor barrier, and roofing components contributed to total system failure. These findings, coupled with significant workmanship issues, led to the premature failure of the roofing system.
TAM Consultants, Inc., Williamsburg, VA
Tim Mills graduated with a bachelor of science degree in engineering from Brooklyn Polytechnic Institute of New York in 1983. He has been a resident of the Tidewater, VA area for 20 years. He is a licensed professional engineer in Virginia, North Carolina, and South Carolina. He founded TAM Consultants, a professional services firm, in 2002. Prior to forming TAM Consultants, Mills had experience with a number of multi-disciplined design and inspection firms and served in the role of designer, inspector, project manager, technical specialist, commercial roofing specialist, asbestos and lead specialist, construction manager, general contractor, and owner’s project representative. His 30+ years of experience cover a wide range of public and private projects of varying types and sizes. Mills has also conducted and led the efforts for many forensic and engineering studies, and provided environmental services (asbestos and lead paint), including bulk, air, and clearance wipe sampling. He has completed property condition surveys for commercial, industrial, retail, and residential buildings, and has also worked as an energy consultant for an electric utility company and chief engineer for a private building inspection firm. He has written numerous articles. Mills has completed nearly 1,500 residential home and commercial building inspections and 300 energy audits. He developed the TAM Consultants’ “Best-Build Enclosure Program” to assist the project team in developing better buildings through a managed approach to construction of critical enclosure elements. He is an instructor for ABAA training courses, which educate and certify contractors in the proper installation of air barriers, as well as a certified ABAA Auditor in the Quality Assurance Program.