Precision at Every Point: Introducing Our Manual Single Point Extensometer

The Geomotion manual Single Point Extensometer is a mechanical and robust instrument for monitoring settlements in-ground.

The Singe Point Extensometer heave/settlement movement is measured using a vernier gauge at the reference head.

The device can be installed under a flush mounted gatic cover for an discrete installation.

The unit can be customised to length on site with simple hand tools.

Speak to Geomotion today to discuss your requirement. Each unit is manufactured on order!

Product Features

  • Cap for 100mm range and grouting
  • Rigid stainless steel adjustment rod, used to connect the brass head to the anchors
  • Fibreglass rod with protective sleeve
  • 300mm SS flange plate with 50mm circular disc used to suspend the extensometer while the grout sets in the borehole
  • Rebar anchor with 65mm flange to stop slip

Product Benefits

  • Suitable for long-term monitoring
  • No electronic components
  • Rod and anchor does not slip in grout
  • Accurate, repeatable readings


Relative movement between the end anchor placed at the subsurface point of interest and the reference head can be measured with a vernier gauge regularly to obtain settlement data.

A specially designed lid has a narrowed opening to guide the caliper to the brass head for accurate, repeatable readings even. The brass head is typically installed at a halfway point to allow for 50% extension and 50% contraction, corresponding to 50mm of heave and 50mm of settlement respectively.


Manual single point extensometers are commonly used in:

  • Underground mines
  • Tunnelling
  • Open cut mines
  • Excavations
  • Dams

Geomotion offer installation and monitoring services to support this system. For more information please email or contact any of our locations.