Soil Testing & Site Classifications

Soil testing in Brisbane is essential for safe and durable construction of residential buildings, extensions, decks, and pools. Accurate site classification ensures foundations are designed to suit the soil conditions, reducing the risk of ground movement, cracking, and structural issues.

SNG Engineers provides professional soil testing and site classification services across Brisbane, in compliance with AS 2870 – Residential Slabs and Footings. Early soil testing can help identify reactive soils and problem sites, saving time and costs before construction begins.

Soil Test Procedure

We conduct thorough soil investigations in Brisbane using a minimum of two boreholes drilled to 2 meters, with testing carried out using a Dynamic Cone Penetrometer (DCP) or Pocket Penetrometer. Soil samples are collected for laboratory analysis to determine reactivity and bearing capacity. Site conditions such as groundwater, drainage, slope, vegetation, and fill are recorded to prepare a detailed soil report for foundation design.

Soil vs Site Classification

Sites are classified based on expected ground movement from soil moisture changes:

  • Class A – Sand or rock sites with minimal movement.
  • Class S – Slightly reactive clay, minor movement.
  • Class M – Moderately reactive clay or silt, moderate movement.
  • Class H1 – Highly reactive clay, significant movement.
  • Class H2 – Very highly reactive clay, large movement.
  • Class E – Extremely reactive sites, very high movement.
  • Class P – Problem sites with fill, low bearing capacity, or other site constraints requiring special engineering.

Soil Testing Services in Brisbane

SNG Engineers offers expert soil testing services in Brisbane for:

  • New Homes
  • Extensions and Additions
  • Decks
  • Raise and Build‑Under Projects
  • Retaining Walls
  • Swimming Pools
  • CBR Sampling

SNG Engineer’s soil reports provide clear, reliable information to support safe, cost-effective, and compliant foundation design, helping Brisbane homeowners and builders make informed construction decisions.

Contact us today for a competitive free quote for your next project.