Where to look
Observe walls, piers, slab edges and service penetrations without entering unsafe areas.
Read the trail and its location
Termite mud tubes: a visual field guide
A termite mud tube may appear as a narrow trail of dried soil crossing masonry, timber or another surface. Not every dirt-like mark is termite activity.
Lookalikes
Splash marks, insect nests and accumulated soil can resemble workings in a photograph.
Do not break it open
Leave the trail intact and capture a close and wide photograph.
Assessment
An inspection can consider the mark alongside other accessible evidence.