What Is Loop Grout?

Loop grout is the thermally enhanced material pumped into a borehole around the loop pipe after installation. It serves two purposes: conducting heat between pipe and surrounding earth, and sealing the borehole so it cannot become a path between aquifers.

Also called: grout · thermal grout · bentonite grout

Why it matters to you

Grouting is invisible once finished and is exactly where shortcuts would not show. It matters both to performance — poor contact degrades heat transfer for the system's whole life — and to groundwater protection, which is why sealing requirements exist.

What to do about it

Ask what grout is specified and whether boreholes are grouted full-length to the surface. This is a specification question for the installer, not something that can be assessed after backfill.