Recently, Christopher Glenn of Langan Treadwell Rollo’s Oakland, CA office moderated a webinar, with panelists Jean Hansen, Sustainable Interiors Manager at HDR and Todd Arris, Senior Director of Development at Kilroy Realty, to discuss healthy building environments and indoor air quality.
Now more than ever, the building industry is making significant advancements in efficiency, sustainability, and technological innovations. Protecting indoor air quality from contaminants that may exist in the soils beneath buildings, as well as materials, furniture, and supplies, is critical to improving and maintaining a healthy work and living environment.
The panel discussion, sponsored by AGRION Global Network for Cleantech, Energy, and Corporate Sustainability, focused on the use of vapor mitigation systems (VMS) as a means of protection of indoor air quality for new development properties. Glenn observed that protection of indoor air quality from contaminants in soils and soil gas is increasingly important given the growing number of new developments on remediated or less than pristine land. Within the San Francisco Bay Area alone, new developments are transforming former industrial properties along the shoreline into new neighborhoods, such as Mission Bay, the site of several Langan environmental and geotechnical projects. Former military properties such as Hunters Point Naval Shipyard and Treasure Island are also undergoing remediation and are poised for redevelopment. VMSs offer protection against vapor intrusion for new development on these brownfield sites or remediated properties.
A VMS typically consists of two components:
- A vapor barrier that is spray-applied beneath the building’s structural slab.
- A venting layer beneath the vapor barrier consisting of a permeable rock layer and perforated piping to capture and vent accumulated vapors from beneath the building to the atmosphere.
A VMS doesn’t have to be costly; by focusing on passively-powered and integrated systems, an ideal VMS design can be incorporated into the existing building design framework in a cost effective and sustainable manner. For example, wind turbines can provide passive but effective suction to transport accumulated vapors through the venting layer, or the venting layer and vapor membrane themselves can also serve as a capillary break and water vapor barrier, which is typically desired in new developments – even where a VMS is not required.
As indoor air quality becomes a focus of environmental health regulatory agencies, the building industry needs to continue to identify ways to protect the quality of indoor air and support healthy building.
What do you think? Have you encountered indoor air quality issues?
Christopher Glenn, PE, LEED GA