Thermoplastic roofing membranes, one of the fastest growing forms of low-slope roofing products, come in different material families, including thermoplastic olefin (TPO), polyvinyl chloride (PVC), and PVC alloy. Some attributes shared by TPO and PVC membranes include long-term weathering resistance, cold temperature flexibility, resistance to tear, puncture, and chemicals, and heat-seaming capability.
Introduced in 1986, the negative pressure roof system remains a niche design in the single-ply roofing industry. Also referred to as a ‘wind-vented’ roof, the science behind the system is simple. When an air seal is formed using a newly installed single-ply membrane, a low pressure condition is created on the underside of the roof. Any moisture in the existing wet roof insulation is pulled up through perimeter roof vents.
The author provides an overview of the 2018 International Energy Conservation Code (IECC), discusses how and why the requirements for the building enclosure have changed, and how the current code will impact design and construction. He explores how climate influences design, the need to control air and water in an enclosure assembly, and the rationale behind reducing the percentage of glass on façades.
High-performing commercial buildings are becoming popular because of evolving codes and stricter standards for occupant safety, comfort, and energy efficiency. One can achieve high-performing building envelopes by combining various cavity insulation solutions, such as foam sheathing and insulation behind brick, stucco, concrete, and other cladding systems.