Lesson Notes By Weeks and Term v4 - SHS 2

Lesson Video

This page supports the lesson note with a companion video and a short classroom-ready summary.

For class groups and homework, share this lesson page so learners also get the summary, objectives, and full lesson context.

Performance objectives

• Describe the different types of foundations.
• Discuss how soil conditions affect foundation choice.
• Explain the relationship between substructure and superstructure.
• Analyze factors that influence foundation selection.

Lesson summary

Every building we see, from the smallest kiosk to the tallest skyscraper in Accra, is divided into two main parts: the part we see above the ground (superstructure) and the hidden part below the ground that supports it (substructure). The most crucial part of the substructure is the foundation. Just like a mighty Odum tree needs strong roots to stand firm, a building needs a solid foundation to be safe and last for generations. In Ghana, where we have different soil types—from the hard laterite in Ashanti Region to the soft clay soils in parts of Greater Accra—choosing the right foundation is a matter of safety, cost, and durability.

Lesson notes

2.1 Substructure vs. Superstructure

The ground level is the dividing line for any building. Substructure: This is the part of the building that is constructed *below* the ground level. Its main job is to transfer all the loads from the building safely to the underlying soil. Components: The primary component is the Foundation. It can also include basement walls and ground floor slabs. Superstructure: This is the part of the building that is *above* the ground level. This is the visible and usable part of the structure. Components: Walls, columns, beams, floors, roof, doors, windows, and finishes. 2.2 The Foundation and Its Functions

The foundation is the lowest load-bearing part of the substructure. It is the building's "feet."

Primary Functions of a Foundation: Load Distribution: It takes the total load of the building (from the roof, walls, people, furniture, etc.) and spreads it over a large area of soil. This prevents the soil from failing under pressure. Anchorage: It firmly anchors the building to the ground, preventing it from being moved or overturned by forces like strong winds or minor earth tremors. Stability: It provides a level and stable base for the construction of the superstructure. Prevents Settlement: A well-designed foundation prevents uneven sinking (differential settlement) of the building, which can cause cracks in walls and structural failure. 2.3 Common Soil Types in Ghana and their Properties

Evaluation guide

• Discuss the various types of foundation used given the soil condition.
• Communication: Organise whole Class and ask learners to explain foundation of
• buildings.
• understanding