The commissioning of a building enclosure is dependent upon the assumption that the construction manager and his contractors have a proactive first level enclosure process fully implemented in order to provide the opportunity for BECx to function and succeed.

William Nash, P.E., is a Senior Project Manager with WDP & Associates, in the firm's Manassas, Virginia office. Mr. Nash offers over 35 years of professional experience in the construction industry which includes field engineering, project management with both divisional and corporate responsibilities, and technical services. His management expertise in facilities and building envelope projects includes a variety of technical disciplines ranging from preconstruction building envelope coordination to construction inspections and forensic investigations. Mr. Nash is certified as a Licensed Field Auditor by the Air Barrier Association of America (ABAA) and is a Level 1 Certified Infrared Thermographer in accordance with the American Society for Non Destructive Testing SNT-TC-1A. He is a member of numerous industry organizations, including the American Society of Civil Engineers (ASCE), American Society for Testing and Materials (ASTM), Building Envelope and Thermal Energy Council (BETEC), Construction Specifications Institute (CSI), International Concrete Repair Institute (ICRI), Roof Consultants Institute (RCI), and The Masonry Society (TMS). In addition to his industry participation on the national level, Mr. Nash is heavily involved with various national standards committees for ACI, ASCE, ASTM, and National Institute of Building Science/BETEC. He is a licensed civil engineer in Virginia, Missouri, Illinois, Indiana, Kentucky, and Texas.

Surprisingly little research has been done into the effectiveness of different drip edge designs. Drip edges are found at window sills, window head flashing, and the edges of roofs and balconies – all critical areas for managing rainwater. By deflecting rain from the exterior surface of a wall, drip edges can reduce moisture-related issues such as freeze thaw of masonry, staining of the cladding, and potential long term erosion of historical materials. In this session, Jonathan Smegal will describe recent research into effective drip edge design. The study he will discuss used a custom-designed apparatus to compare the effectiveness of different drip edge materials, profiles and overhang distances. The results show a significant range in performance. Based on these results, practical guidelines will be suggested for choosing the best drip edge for your project.

Jonathan Smegal’s work for BSCI includes laboratory research, hygrothermal modelling, field monitoring of wall performance, and forensic analysis of building failures. He worked for Balanced Solutions from 2005-2007, joining BSCI in 2007 after finishing his thesis on Drainage in Small Cavities in Wall Systems as part of the Building Engineering Group at the University of Waterloo. Jonathan’s research has included, among other things, cladding deflection tests, drainage balance testing and specialized water uptake and vapour permeance testing. His experience in the lab is complemented by his experience in the field, where he has been involved with forensic work and numerous new construction site audits for residential and commercial construction. As a speaker, Jonathan has addressed a range of audiences at academic conferences, corporate training events, and online. For example, he presented papers at the 2013 Buildings XII Conference and at the 2014 Canadian Building Science and Technology Conference, and has spoken at workshops and other events on diverse topics including cladding attachment, SPF in cathedral ceilings, and rainwater management in wall systems.

Lothar will make a series of expert presentations from Vancouver BC to San Francisco CA. Lothar will present how to build safe, healthy and durable constructions that maximize energy savings, minimize the risk of damage to the structure and prevent mold and rot for wood framed and masonry retrofit assemblies with in-depth discussion of building physics, including WUFI analysis and assembly options specific to our climates in the Pacific Northwest and Northern California.

2 LU

Cold applied liquid applied waterproofing and roofing membranes of various chemistries (e.g. polyurethane, polyurea, polyester, and asphalt modified urethanes etc.) have become increasingly popular in past decades, particularly over concrete podium slab, roof decks, and planters in protected (i.e. inverted) roofing applications. Liquid membranes are often preferred in this application for their relative low cost, ease of application over complicated curbs, planters, water features and at penetrations and interfaces. While cold-applied membranes have their benefits in waterproofing – they have had their share of problems.

Over a decade ago, the roofing industry began to find systemic water-filled blisters under many of these cold-applied membranes, in cases so severe that the premature replacement of these membranes has now become commonplace. Field studies have shown that these water filled blisters become visible within the first 5 years of service and progressively get worse and grow over time with expanding pressure until entire roof areas are consumed. Water leaks occur with time and displaced or floating pavers and other landscaping components are also a common side effect. A decade ago, the cause of the blisters had the industry scratching its head and a wide range excuses from inadequate membrane thickness and pin-holes, detailing, shoddy workmanship, to outward vapor drive were supposedly to blame.

Being curious as to what was actually causing these water filled blisters to form, a study was initiated to find the physical building science mechanism responsible. This study encompassed field studies, building monitoring, and several iterative laboratory experiments, until eventually the water transport process of osmosis was confirmed. This presentation covers the story of how the phenomenon of osmosis was discovered, the physical mechanism of osmotic blistering and the scenarios where it can occur, and the new testing protocol developed. The test results for a wide range of new and aged membranes commonly used within the roofing and waterproofing industry will be presented along with recommendations for the material properties needed to prevent blistering from occurring.

Graham is a Principal and Building Science Research Specialist with RDH. He has a passion for technology and for making better and more energy efficient buildings. He leads RDH’s building science research group and is actively involved in a wide range of projects from building research studies to forensic investigations, building monitoring, hygrothermal modeling, and new construction across North America. Graham has authored several publications and practical industry guideline documents related to durable and energy efficient building enclosures. In addition to RDH, Graham is a part-time instructor at the British Columbia Institute of Technology where he teaches building science courses to students at the Diploma and Masters levels.