Spherical Block is the only company in the world building roofs with concrete blocks. This is a very efficient and resilient way to build, the arches of the Roman Aqueducts are standing 2,000 years after construction. Fire and extreme weather safe.
Please read this cover article for Masonry Magazine about our Arch Block and Dome block systems-
https://www.masonrymagazine.com/blog/2020/07/21/spherical-block-llc-a-new-way-to-build-with-masonry/