Advanced vapor barrier technology protects indoor air quality on brownfield redevelopment sites
A recently developed composite membrane system, Geo-Seal™, offers exceptional chemical resistance for use as a gas vapor barrier on construction sites with environmentally impacted soil and/or groundwater. This new technology was announced in a key platform presentation at the recent Sixth International Symposium on Remediation of Chlorinated and Recalcitrant Compounds in Monterey, California.
Developed by Land Science Technologies, a division of Regenesis (San Clemente, CA), Geo-Seal (patent pending) is the first vapor barrier technology to combine the durability and chemical resistance of two bonded high-density polyethylene (HDPE) layers with the ease and quality of installation found in a basic spray-applied asphalt/latex barrier.
“The authorities overseeing the development of environmentally impacted parcels have become more concerned about the long-term performance of simple, spray-applied, asphalt-type vapor barrier membranes,” Regenesis CEO Scott Wilson explained. “The Geo-Seal system actually encapsulates a proprietary spray-applied layer between two layers of bonded HDPE material, making it dramatically more effective in stopping subsurface contaminant gases from moving through a foundation, and providing an order-of-magnitude improvement in long-term performance when compared to typical spray-applied products on the market.”
Brownfield site development often requires a vapor barrier to prevent volatile organic contaminants in the subsurface from migrating into newly constructed buildings. Historically, polyethylene or other plastic sheeting has been used for this purpose, but their use requires labor-intensive seaming, making installation often difficult and costly. More recently, spray-applied asphalt/latex waterproofing materials have been promoted as a reasonable solution; however these materials are now known to have a high affinity for contaminant vapors, which over time will partition into the membrane material itself potentially moving through the vapor barrier and impacting indoor air quality.
Geo-Seal is a composite vapor barrier technology installed on-site prior to foundation construction. Data presented at the Monterey symposium, generated in controlled laboratory analyses, indicated that Geo-Seal was 645% more protective against volatile organic vapor transmission than commercially available spray-applied asphalt/latex products, with <0.16 the contaminant permeance, and resistance to contaminant permeation breakthrough for a period 18X longer.