Cemcast Pipe and Precast manufactures all pipe, arch pipe, and manhole products with a single-offset gasket joint. These gaskets ensure a watertight connection to 13 psi when installed properly. The 13-psi rating is equivalent to a column of water 30’ deep. To achieve such a high psi rating, the single-offset joint is precisely manufactured with minimal annular space for the gasket. When installing manholes, following the same basic steps detailed in our concrete pipe section to ensure trouble-free watertight connections.