There are two types of process:
In one, a fiberglass liner is spun in the pipe; in the other an inflatable sock is inserted into the pipe, epoxy is introduced and heat from the hot air or water in the sock cures the epoxy.
However:
(i) the epoxy curing process can off-gas chemicals that cause temporary eye irritation, light-headedness, nausea, vomiting (I know - happened to me recently when a sewer line in the street was being lined)
(ii) the liner will not effectively bridge misaligned, broken, collapsed or root-filled pipes. CCTV camera surveys of the drains and routing-out of roots etc is required first as a precursor to decisions on whether to reline or target replace drains.
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John Fidler RIBA IHBC Intl. Assoc. AIA. FAPT
President & Chief Technical Officer
John Fidler Preservation Technology
Marina Del Rey CA
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