When this service is useful
The right scope depends on your development, site access, ground conditions and the information needed by your project team. This service is commonly used for:
- New dwellings and multi-unit residential projects
- Commercial buildings and light industrial development
- Basements, retaining walls and constrained excavation projects
- Pavements, accessways and hardstand areas
- Sites with fill, soft soil, rock, groundwater or uncertain conditions
AS 1726 investigations matched to the proposed development
A geotechnical site investigation should answer the actual design and approval questions rather than simply generate a standard set of boreholes. The appropriate scope can vary with proposed loads, investigation depth, excavation, neighbouring assets, ground variability, access and available construction information.
Published mapping may indicate Hawkesbury Sandstone, Bringelly Shale, alluvial deposits or other Sydney Basin units, but mapping is only a starting point. Actual weathering, fill, groundwater observations and founding conditions need to be assessed for the individual site.
Field methods are selected for the required depth, expected ground and safe access. A scope may use boreholes, DCP testing, test pits, soil or rock sampling and targeted laboratory testing. Specialist methods such as cone penetration testing are not assumed to be included unless they are specifically identified as necessary and included in the agreed scope.
Important project and ground considerations
- Investigation locations and depths proportionate to the development footprint
- Potential soil, rock, fill and groundwater constraints
- Foundation bearing, excavation, retaining-wall, pavement or earthworks questions
- Construction-stage inspections and verification where identified by the investigation
- The exact DA, CDC, council, certifier or design-team request—because a geotechnical report is not automatically required for every development
What the assessment can include
- Review of project drawings, proposed loads and Sydney site constraints
- Boreholes, test pits, soil and rock sampling or DCP testing selected to answer the project questions
- Engineering description of soil, fill, weathering and rock conditions
- Laboratory testing coordination where it will materially inform design
- Groundwater observations at the time of investigation and clear limitations on short-term observations
What you receive
- Interpreted subsurface profile and investigation results
- Foundation options and founding-depth recommendations
- Allowable bearing-pressure guidance subject to project conditions
- Earthworks, excavation, drainage and pavement advice where relevant
- Construction-stage verification requirements
What to provide for your quotation
The clearest quote starts with enough information to understand your actual project, site constraints and required deliverables.
- Site address, survey and architectural or structural drawings
- Proposed building loads, excavation depth and development type
- Available previous reports, service information and access photographs
- Any specific council, certifier, structural or civil engineering questions
Geotechnical Site Investigations across Sydney and NSW
Investigations can be scoped for residential, commercial and development projects throughout Western Sydney, South West Sydney, Macarthur, Parramatta and the Hills District, the Blue Mountains, Northern Beaches, Eastern Suburbs, Sutherland Shire and the Illawarra. Ground conditions and approval requirements must always be considered site by site.