How many boreholes does a soil report usually require?

This genuinely varies with your site’s size and the complexity of the assessment needed — a standard residential soil report commonly involves several boreholes across the site to properly capture soil variation, rather than relying on just one.

Larger sites, or sites with reason to suspect variable conditions (evidence of past fill, for instance), may need more boreholes than a smaller, straightforward, uniform block.

Your geotechnical engineer determines the appropriate number and location of boreholes for your specific site as part of proper assessment methodology — not a fixed number applied regardless of site size or complexity.

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