Project Highlights

  • Retro-Coat functioned as a vapor intrusion mitigation membrane as well as a long-lasting coating for the basement level, accomplishing two of the owner’s goals with one product.
  • Retro-Coat was chosen as the most feasible and effective treatment due to compatibility with pre-existing methane mitigation system components.
  • Retro-Coat is resistant to harmful methane gas intrusion and is a wearing surface, meaning no additional concrete protection is necessary.
  • The updated vapor intrusion mitigation system allowed for the new tenants to move in quickly.
  • Retro-Coat is applied without any odor and cures quickly, reducing building downtime.

Project Summary

An office building located on the San Francisco Peninsula was left vacant for multiple years. The building is located on top of a capped landfill which is a known methane producer. After a recent change in ownership, it was important for the new owner to make the necessary improvements to the building so that new tenants could move in quickly. One of these improvements was to update the vapor mitigation system to ensure the tenant’s safety from any harmful vapor intrusion.

The owner enlisted the expertise of Langan to update the vapor mitigation system. Langan proposed using Retro-Coat Vapor Intrusion Coating System because of its proven resistance to harmful vapors and its durability. The owner was thoroughly pleased with this application because it accomplished two goals with a single product: it mitigated the harmful vapor intrusion and provided a durable coating for the floor of the basement level. Retro-Coat’s multi-functionality saved the site owner time and money.


Technology Description

Retro-Coat Vapor Intrusion Coating consists of chemically resistant materials which protect existing structures from the threat of contaminant vapor intrusion. Retro-Coat was developed by experienced vapor intrusion specialists and is proven to resist the most aggressive chemical vapors. This technology acts as a protective barrier eliminating the need to remove the existing slab and when combined with in situ treatment, it can greatly lower remediation costs.



Retro-Coat consists of chemically resistant materials which will protect this structure from the threat of contaminant vapor intrusion, specifically methane gas. Retro-Coat finishes to a high gloss, easy-to-clean surface that is impervious to vapor and moisture transmission. Additionally, Retro-Coat withstands foot traffic and industrial settings. It was significant to have a highly durable coating system in place because the tenants plan to use the basement level to house large computers and heavy technological equipment.

The site owner has been very pleased with the outcomes from Retro-Coat. The building’s basement level has a highly durable coating and most importantly, the vapor intrusion mitigation system is now highly effective.