In short, CIPP lining is inserted into the existing, damaged pipe where an epoxy resin mixture allows it to harden in place, thus creating a new pipe. This new sewer pipe is slightly smaller in diameter than the exiting pipe, but flow rates are still improved because it is smoother, which allows water to flow unimpeded.
CIPP liners come in all sorts of shapes and sizes, and some are even custom-made for a particular Seattle pipe lining job. CIPP liners are made from non-woven polyester felt. The exterior of the felt is coated with polyurethane. The epoxy resin mixture is introduced into the felt, which acts as a medium for the resin, making it stronger when cured.
At the job-site, the CIPP liner is inserted into the old pipe from one small hole, usually at an access point within the sewer pipe conduit. Once the Seattle pipe lining technician has the liner in place, a bladder is inflated to press it into the interior wall of the old pipe. The heat from the inflated bladder sets the resin. When it’s set, the liner is slowly cooled. This prevents the new pipe from shrinking.