Cleaner Air is Safer Air

cleaner air

Vapor Mitigation Strategies’ team completed the piping from the vapor pits to the risers for the SSDS, installed the AVB, and installed four vapor monitoring wells to ensure there was no vapor intrusion at D.C. early childhood centers, ensuring student safety.

A national chain of early childhood education centers chose the location of its Washington D.C. project on property known to have soil and groundwater contamination left behind from its former uses. The building designers were cognizant of the potential for vapor intrusion risk which might present itself to a sensitive population and researched design options.

Their choice was to employ a vapor intrusion mitigation system, which included a combination of two elements: an active pump sub-slab depressurization system (SSDS) component, and a spray-applied asphaltic vapor barrier (AVB). The SSDS consists of two square subterranean concrete vault “pits” with slotted openings at the top, and piping running from the pits to risers penetrating the sub-floor.

Both vapor pits were installed as part of the General Contractor’s (GC) pre-vapor intrusion mitigation installation commitment to provide for large scale construction items prior to the finishing of the SSDS and AVB by vapor intrusion mitigation installation specialists.

The GC accomplished pre-installation work which included construction of the vapor pits, all plumbing and electrical penetrating uprights, concrete collars around clustered penetrating uprights, smooth-grinding of rough surfaces for attachment of AVB to the foundation, and constructed and compacted the sub-slab gravel bed.

Vapor Mitigation Strategies’ team completed the piping from the vapor pits to the risers for the SSDS, installed the AVB, and installed four vapor monitoring wells.

The AVB was installed using a three-layer approach. First, by applying a polypropylene tarp which was rolled out tailored to fit around the vertical uprights and sealed to the foundation or uprights with Geo-Seal.

After the tarp was completely rolled out and all uprights and edges were addressed and sealed, the core layer of Geo-Seal was sprayed over the entire area.

Then, a final layer of tarp was installed to provide protection to the vapor barrier itself since metal rebar and concrete were layered on top.

www.vapormitigationstrategies.com

This article originally appeared in the School Planning & Management February 2018 issue of Spaces4Learning.

Featured

  • Duncanville High School Breaks Ground on New CTE Building

    Duncanville High School in Duncanville, Texas, recently held a groundbreaking ceremony for the newest addition to its campus, a Career and Technical Education (CTE) facility. The new building is part of a larger CTE expansion project for the school included in a 2023, $170-million bond program.

  • Kimball International Debuts Health & Education Experience Center

    Kimball International recently opened a new facility at its corporate headquarters in Jasper, Ind., that will act as a hands-on showroom for a variety of its furniture products and solutions, according to a news release. The 13,000-square-foot Health & Education Experience Center was originally designed by Gensler as the headquarters for Kimball International’s National brand.

  • Abstract colorful arrows in front of a contemporary university building

    Spaces4Learning 2025 Trends in Higher Education

    With 2025 well underway, it’s time to take a look at some broader trends submitted by you, our Spaces4Learning readership. We asked for your thoughts on topics like classroom design, health & safety, materials & construction, and technology in both K–12 and higher-education environments. Below is a roundup of 2025 trends in higher education from the experts in the trenches.

  • Ancient Resilience: How Indigenous Intelligence Shapes the 4Roots Education Building

    As climate change intensifies, educational spaces must evolve beyond basic sustainability toward true resilience – we must design environments that can adapt, respond, and thrive amid shifting, and intensifying, climate hazards. Drawing on indigenous wisdom and nature-based strategies, integrating resilient design offers a path to create learning environments that are not only functional but deeply in tune with their natural surroundings.

Digital Edition