Residential Building Inspector Practice Exam

In the absence of a complete geotechnical evaluation, what is the presumptive load-bearing value of silty gravel material?

1. 1,500 PSF

2. 2,000 PSF

3. 2,500 PSF

4. 3,000 PSF

The correct answer is: 2,000 PSF

The presumptive load-bearing value of silty gravel material is typically considered to be around 2,000 pounds per square foot (PSF) when a complete geotechnical evaluation is not available. This value is derived from standard assumptions used in geotechnical engineering, which provide a general guideline for the load-bearing capacity of various soil types. Silty gravel, being composed of granular material mixed with fine particles, is generally competent to support moderate loads. In engineering practices, adopting a presumptive value is a common approach to ensure that the foundation design can proceed without the delay or cost associated with a full geotechnical study. For safety and compliance with building codes, practitioners often rely on these values, which have been established through historical data and testing. This ensures that even without a detailed site-specific analysis, the structure can be designed to manage the expected loads based on reliable conservative figures.