When roadway reconstruction raises the pavement level, manholes need to be repositioned so that they are once again level with the street. Typically, heavy concrete rings are used to build up the chimney so that the cover and its frame can be repositioned.A new alternative is the PRO-RING system, a series of lightweight expanded polypropylene (EPP) rings that can be used to raise a manhole to grade level. PRO-RING is manufactured by JSP from the company’s ARPRO brand EPP material. It is distributed by Cretex Specialty Products, of Waukesha, Wis., a supplier of chimney seals and other manhole repair products.
