The First Church of Christ, Scientists is a unique Monolithic Membrane 6125® application where the water feature was waterproofed with the standard MM6125® fabric-reinforced assembly, filled with water to create the reflecting pool, and more than 50 years later the membrane has been performing in a continually submerged condition since 1971. As a monolithically applied material that has no seams, the membrane is designed to be in fully submerged conditions indefinitely and be guaranteed for watertightness.

In addition to the reflecting pool, the surrounding three buildings also used MM6125 as their waterproofing membrane of choice, placing insulation and gravel ballast as overburden, creating a Protected Membrane Roof Assembly. This project totals 400,000 square feet with the majority being the reflective pool, which is still waterproofed with MM6125.

This project highlights Monolithic Membrane 6125’s ability to protect zero slope applications for the life of a structure and has led to opportunities for Hydrotech to develop assemblies addressing stormwater detention solutions.

More recently and driven by sustainable efforts, this iconic I.M. Pei design recently went under construction to reduce the depth of the reflective pool and shorten it by 16 ft. During that time, MM6125 was tested for its watertight integrity after nearly 50 years of performance and positive results came back saying that there was no issues with the membrane. Due to the depth change, the membrane had to be removed but it was explicitly decided that Hydrotech® Monolithic Membrane 6125® would be reapplied to protect the pool indefinitely.