Soil testing — known as borehole testing — is essential before any construction project. Determining soil type and bearing capacity directly affects foundation design and building safety.
What Are Boreholes?
A borehole is drilled into the ground using specialized equipment to extract soil samples at various depths. These samples are tested in a laboratory to determine soil type, bearing capacity, groundwater level, and salt content.
Common Tests
Standard Penetration Test (SPT), direct shear test, unconfined compression test, grain size analysis, and Atterberg limits for clay soils.
Relation to Surveying
Surveying determines land boundaries, levels, and foundation positions, while soil testing determines appropriate foundation types and depths. The surveying office plots borehole locations on the site map and links them to the overall survey.
Costs in Egypt 2026
A borehole 10-15m deep costs 3,000-7,000 EGP. For a typical house, 2-3 boreholes cost 10,000-25,000 EGP including the report.
EL EMAN Office helps coordinate soil testing with land surveying for your project in Alexandria and across Egypt.
How soil testing is carried out on site
Soil testing begins by deciding the number, location and depth of the boreholes based on the building footprint, the number of floors and the nature of the area. Boreholes are drilled with suitable equipment, samples are taken from the different soil layers, and the groundwater level is recorded if present. The samples go to a laboratory for tests that determine the soil type and properties.
- Classification tests and grain-size analysis.
- Strength and bearing capacity tests.
- Chemical analysis of groundwater and soil to see how salts and sulphates may affect concrete.
What depends on the soil report
The structural engineer relies on the report to choose the foundation type (isolated footings, strip footings, a raft or piles), the foundation depth, and how to deal with weak layers or soils that swell or settle. The report also guides the right cement type and waterproofing methods where groundwater is high or saline. Skipping this step can lead to uneven settlement and cracks in the building.
Reading the report and avoiding errors
It is not enough to receive and file the report; the designer and the contractor must understand its notes. Borehole results represent specific points, and soil may vary from one point to another, so if the actual excavation shows a noticeable difference, tell the engineer immediately.
It also helps to carry out a survey first so the boreholes can be located accurately on the ground.
Common mistakes in soil investigation
The most frequent mistake is settling for a single borehole on a large plot, which hides variations in the rest of the site. Another is testing at a time when the groundwater level is temporarily low, so problems that appear later are missed. Some people ask for a ready-made report from a nearby site on the grounds that the land is similar, which is risky because soil can change over short distances.
If the land was recently filled, the report should note it, because uncompacted fill causes uneven settlement. Sharing the soil report with the contractor also helps, so they know the excavation conditions and can prepare pumps or shoring when needed.
Frequently asked questions
Is soil testing needed for a small house?
It is recommended for any building. Its cost is usually small compared with the problems a foundation error can cause, and the licensing authority may require it.
How long do the tests take?
The time depends on the number of boreholes, the tests required and the laboratory schedule, and is agreed in advance with the contractor performing the work.
Does the report change over time?
Groundwater conditions or the site itself may change. If a long time has passed or major filling has taken place, the engineer should review whether an update is needed.
