Steep slopes and ice dams, beware. Defend-R Vent is here.

By Drexel Metals.  

Explore Drexel Metals’ newest member of the Defend-R club.  

Early in July, Drexel Metals announced the addition of a new product to their Defend-R line, a collection of polyisocyanurate panels designed for roof insulation. Defend-R Vent, the shiny new toy, is a ventilated composite insulation panel designed for steep-slope roofing applications. The board consists of three layers: a 4-foot by 8-foot bottom layer of closed-cell rigid polyisocyanurate, a middle layer of solid wood spacers that create a standard 1-inch air space gap and a top layer of APA/TECO-rated OSB or plywood. These three layers work together to provide ventilation as well as insulation, making it a smart choice for sustainable applications. Below are some of the Defend-R Vent’s key features.  

Prevent ice dams before they start — The power of Defend-R Vent  

Ice dams form on roofs due to heat escaping from inside a structure. This heat rises and warms the roof surface, causing snow to melt. As temperatures drop overnight, the melted snow refreezes — most commonly at the eaves. Over time, repeated cycles of melting and refreezing cause ice to build up along the roof edge, gradually working its way up the slope. This accumulation creates a barrier, or “dam,” that traps additional melted water behind it. With nowhere to go, the water backs up beneath the roof covering, potentially leading to various roof system performance issues and leaks inside the building. 

With its three layers, Defend-R Vent is a ventilated insulation product that can prevent ice dams from forming. The length of the rise and run determines which airspace will be the most efficient for a roofing system. The finished roofing system — metal, shingles, shakes or tile is installed over the Defend-R Vent panels. Defend-R Vent also features cross directional airflow keeping the roof temperature constant, further eliminating hot and cold spots on the roof where ice dams are formed. 

If air is allowed to flow under the finished roof assembly, the temperature on the roof will remain cooler and more consistent. A ventilation system under the finished roof system can be achieved with Defend-R Vent. 

Other key features and benefits of Defend-R Vent: 

• Enhanced passive ventilation: Defend-R Vent incorporates a built-in 1-inch air space with wood spacers, providing over 92% open air space and 75% lateral air movement. 
• High R-values: Polyiso core delivers R-5.7 to R-20.5 for strong thermal resistance and energy efficiency. 
• Extended roof life: Defend-R Vent reduces heat buildup and thermal stress, helping protect panels and materials for longer-lasting roof performance. 
• Moisture control: Ventilation helps reduce trapped moisture, preventing mold and damage, especially in humid climates. 
• Sustainable and compliant: Made with eco-friendly NexGen Chemistry™, Defend-R Vent meets key codes like ASTM C1289 and the IBC. 

Material can be ordered through a Drexel Metals Order Management Specialist (OMS). There is no minimum order quantity, and the lead time is typically about one week. Orders will ship from the closest production facility. Take a deeper dive into Defend-R Vent on the Drexel Metals Defend-R Roof Insulation page or request physical samples and literature directly via the online order form. 

Original article source: Drexel Metals