External Watertight Chimney Seal

Versatile & Economical

Get the best performance and save labor costs over the long haul with Cretex’s External X-85 Seals. The high-performance watertight seal is used between the manhole casting and the concrete cone. Cretex’s state-of-the-art technology combines all of the advantages of a mechanical seal in a more economical, easy-to-use option. The X-85 has a 25-year warranty that is unrivaled.
External Watertight Chimney Seal


Our high-performance seal requires no primers, torches, or special tools to create a watertight barrier. The securing band adds additional compression to the sealing fins, instantly filling any minor voids or irregularities. Installation is easy, fast, and safe.

UV REsistant

The Cretex Specialty Products X-85 external mechanical chimney seal is made of EPDM rubber. EPDM rubber is a synthetic rubber and can withstand general weathering, Ozone, and UV making it ideal for above-ground applications if required—structural Integrity for the long haul.

Watertight Seal

The secret to our watertight promise is our Unique “C” shaped band. The top band of the seal is designed to add compression to the inner rubber sealing fins, uniformly filling the annular space between the frame and the cone. The resulting seal forms a watertight barrier around the top, bottom, and outer edges of the frame’s base flange. The “C”-shape band mechanically locks the seal on the manhole casting for lasting performance.