Executive Plaza was once a 24,000-square-foot office building located in East Bellevue, Seattle. HAL and Intracorp partnered to acquire and redevelop the property into 31 townhomes. The former structure was built in the 1970s, and the new homes will feature two-car garages and rooftop terraces and are designed to generate “an open and inviting atmosphere,” in the neighborhood according to Freiheit, the design architect.

Older sites tend to have many uses before arriving at their modern purpose, and this area was no exception. Due to an underground spill many years ago and a subsequent contamination plume, the architect determined that a vapor barrier would preemptively protect the site. Initially, the team felt that a simpler vapor intrusion mitigation system with taped seals would suffice.

However, as installation began, it was determined that a more robust solution was required, and Chris Jones, Superintendent, Intracorp, the project developer, explained why a new product was necessary:

“It was determined that the initial system needed smoke testing,” he says. “When we found EPRO, we were really sold on them – the smoke testing was included in the pricing and their product was exactly what site conditions demanded. From our experience, we know that it’s always a lot better for peace of mind and consistency having the people working with the product also doing the testing because they know what is required and have done it hundreds of times before.”

Geo-Seal EV40s was chosen, and 10,300 square feet was installed under slab to protect the site. Lizard Waterproofing and Deck Coatings LLC was the EPRO Installer.

“We are very familiar with this system,” says Ken Betts, Owner, Lizard Waterproofing. “Installation was pretty quick and uncomplicated on this site, and we appreciated the collaboration with all trades.”

Geo-Seal EV40s is ideal for lower risk sites where site concentrations are at or below state-specific screening levels or large, wide-open, flat sites where speedy installation times are required. It’s also a perfect complement to projects that seek to implement active sub-slab ventilation systems. Geo-Seal EV40s utilizes Geo-Seal CORE spray membrane to seal seams, detail penetrations, and terminate the membrane to concrete surfaces. This method of seaming outperforms simple tape sealing and allows for barrier smoke testing to ensure a vapor-tight seal.

“The product seems to work really well,” Jones adds, “The team were really professional and got the job done efficiently so we could stay on schedule – and that was a big help to us.”
He concludes, “EPRO are there to help, make sure everyone is aware of what needs to be done, and they ensure that everything is done safety and correctly.”