Basic Wall Systems and their Moisture Control Mechanisms November 27, 2020 In June 1962, the first sentence in J.K. Latta’s Canadian Building Digest (CBD-30) article noted, “It has sometimes been stated that there would be no need for building research were it not for the effect of water in the wrong places.” While Latta admitted the statement was an oversimplification, as building enclosure professionals, a large […] Read More
Retrofit Single-Ply Roof Systems Over Metal Roofs: Design, Analysis, and Physical Testing October 11, 2020 Metal buildings with metal panel roof systems are commonly used across the United States, and a retrofit single-ply roof system (RSPRS) is often installed on top of the metal panel roof after it has been determined that it no longer provides useful service. Before discussing retrofit single-ply installations, it is necessary to mention that there […] Read More
Building Science Helps Defeat Coronavirus October 11, 2020 OctobeOBEr 2020 IIBEC • 27 It appears that 100% fresh-air ventilation will significantly reduce and possibly prevent transmission of COVID-19 by virus-carrying aerosolized particles that become airborne rather than falling to the ground out of the 5-ft. (1.5-m) plume emitted from the mouths of infected building occupants. Recent research has shown that increasing the outdoor […] Read More
Where Has All the Counterflashing Gone? October 11, 2020 The use of counterflashing in buildings has a lengthy history. Though perhaps not the earliest definition, The Architect’s and Builder’s Pocket-Book (1886) defines counterflashing as “laid between courses of brick, and turned down over the flashings.” Historically, the importance of competent counterflashing at masonry walls, including roof-to-masonry transitions such as residential chimneys, has been appreciated […] Read More
Raising the Bar in Standards: The ASCE 7 Standards and Low-slope Roof Drainage September 15, 2020 Three important safety issues related to low-slope roofing are: 1) fires on roofs from internal or external sources, 2) roof collapses resulting from the ponding of water (and snow, where present) from extreme storms, and 3)roof blow-offs from extreme windstorms. Fire safety falls within the realm of fireengineering, and the two important U.S. organizations focusing […] Read More
Code Ambiguities and Minimum Standards: The Importance of Code Clarity and Readership September 11, 2020 Building codes are routinely described as the minimum standards intended to hold builders accountable and protect the health, welfare, and safety of the public. But most individuals may not realize that state and local code enforcement departments are not directly funded by taxpayers. According to the website of the Metropolitan Government of Nashville and Davidson […] Read More
U.S. Building Enclosure Resource Guide September 11, 2020 Section 107.2.4 of the 2018 International Building Code (IBC) requires a design professional to include exterior wall envelope information on every set of construction documents as follows: Construction documents for all buildings shall describe the exterior wall envelope in sufficient detail to determine compliance with this code. The construction documents shall provide details of the […] Read More
2021 IBC Provisions for Performance-Based Design and Prevention of Roof Aggregate Blow-Off August 11, 2020 INTRODUCTION Low-slope built-up roofing (BUR) systems have featured stone aggregate surfacing for decades. The aggregate serves several purposes; the primary role is to protect the asphalt material from exposure to ultraviolet (UV) radiation, but the material also offers additional benefits such as insulating, thermal mass, and solar reflectance. In fact, aggregate-surfaced roof systems have been […] Read More
Parapets: The Critical Juncture Between Roofs and Walls August 11, 2020 The parapet is so much more than the intersection of roof and wall. It is also the junction where building aesthetics meet structural performance, air and moisture management, energy efficiency, construction trade sequencing, and operational maintenance. Each of these perspectives is critical for the long-term performance of the building, but they are often at odds […] Read More
Testing Field-Aged TPO Roofs; Demonstrating Real-World Performance July 11, 2020 INTRODUCTION Single-ply membranes are currently the biggest segment of the commercial roofing market. Within that segment, thermoplastic polyolefin (TPO) is both the largest and the fastest-growing sub-category. The first TPO roof in North America was installed as a demonstration project in 1986,1 and the membrane was commercialized around 1990.2 Since then, the installed area of […] Read More
