glossary Glossary 2 min read

Termite mud tube

A termite mud tube is the earthen shelter tube subterranean termites build to cross an exposed surface. Compliant barriers force the tube into the open.

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A termite mud tube (or shelter tube) is the earthen tunnel subterranean termites build to cross an exposed surface, typically up an exposed slab edge or down from a roof void. Termites need to stay enclosed in their moist underground environment; when forced into the open by a termite barrier, they build a mud tube to bridge the exposed zone. The mud tube is what a termite inspection looks for.

How the tube reads

AS 3660 barriers don’t kill termites; they force them into the open where the tube is visible at inspection:

  • Fresh and moist = active colony.
  • Dry and crumbly = past activity, possibly abandoned.
  • Multiple tubes = significant activity, urgent action.

Where tubes appear

  • Up the slab edge through the termite inspection zone.
  • Down from roof or upper-storey wall (entered higher via bridging).
  • Across smooth surfaces (concrete piers, metal stumps) where the termite can’t cross undetected.

Bridging vs visible tubes

A bridging termite found a hidden entry path bypassing the barrier. Keeping the inspection zone clear is what forces any entry attempt to build a visible tube.

For a builder

  • Keep the inspection zone clear at handover. Landscaping built to the slab edge hides the tube.
  • Brief owner on annual AS 3660.2 inspection cycle.
  • Don’t paint or render over tubes in reno. Pest tech needs the evidence first.

Category: Termite management.

See also


Last updated: 2026-05-29. Verified: 2026-05-29. Quarterly review for currency.