Sub Surface provide Geotechnical Foundation Design Reports for new and failed foundations, from small residential extension projects, to large football stadium and high rise projects nationwide.

For each project we provide a site specific, cost effective Ground Investigation, using the appropriate intrusive techniques to obtain information regarding the geology and hydrology of the site.

The Ground Investigation along with In-Situ-Testing and Monitoring and Laboratory Testing will enable an assessment of the suitability of an appropriate Foundations Design. Typical Foundation Designs may include:

  • Strip footings and Pad Foundations
  • Trench Fill Foundations
  • Raft Foundations
  • Semi-Raft Foundations
  • Piled Foundations
  • Ground Improvement by Vibroflotation

What to expect within our Foundation Design Interpretive Reports

All our Interpretive Reports are written to the current British Standards, Eurocode 7 Standards and National House Building Council (NHBC) Standards and where appropriate, typically include:

  • Engineer Logs
  • In-situ Testing
  • Laboratory Testing
  • Shrinkage and swelling potential of clays/silts (cohesive strata)
  • A preliminary Foundation Design
  • Safe Bearing Pressures and/or Pile Loads
  • Floor Slab Construction
  • Groundwater Information
  • Concrete Classification – Design Sulphate (DS) Class and Aggressive Chemical Environment for Concrete (ACEC) Classification

Additional items commonly incorporated within our Interpretative Reports include:

  • A full Geology and Mining Appraisal
  • Earth Pressure Coefficients for Retaining Walls and Basements
  • CBR Values for Roads, Car Parks and Hardstandings
  • Percolation and Soakaway Tests
  • Settlement Calculations
  • Slope Stability Analysis
  • Contamination Analysis
  • Landfill Gas Assessment

It should be noted that when developing a brownfield site and many greenfield sites, the Local Authority generally apply a prerequisite on the Planning Conditions requiring a Phase 1 Desktop Study prior to a Phase 2 Ground Investigation.

Failed Foundation Designs

We also provide Geotechnical Reports where buildings and structures show signs of subsidence. A review of the site, usually a walkover survey will be undertaken, followed by a Ground Investigation to specifically investigate the possible cause of the subsidence. Our report will look to determine the reason for the subsidence and provide suitable remedial measures, such as underpinning by strip footings and pad foundations, piling or grouting, etc. to help arrest any further subsidence.

Whom to Contact

If you would like a quote for a Foundation Design Interpretative or Factual Report, or have any questions, please do not hesitate to contact your Regional Sub Surface Office.