Class: Senior Secondary School 1 (SS1, SS 1, SSS1, SSS 1)
Term: 2nd Term
Week: 9
Age: 15 years
Duration: 45 minutes
Subject: Building Construction
Curriculum Theme: Building Construction
Previous Lesson: Foundation: Meaning and Functional Requirements.
Topic: Foundation: Strip, Raft and Pile Types
Subject Matter: types of foundation strip raft and pile, situations for using each type, basic features of each foundation type, sketches and models of foundations

Specific Objectives

By the end of the lesson, pupils should be able to:

Cognitive Domain:

Define foundation.
State three types of foundation.
Describe the basic features of strip, raft, and pile foundations.
Explain situations where each type of foundation is used.

Affective Domain:

Appreciate the importance of selecting the correct foundation for a building.
Show interest in learning about different foundation types.

Psychomotor Domain:

Sketch simple diagrams of strip, raft, and pile foundations.
Identify different foundation types from given drawings or models.

Participate actively in class discussions on foundation types.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Basic Technology (JSS, relevant for SSS foundation).
State Unified Scheme of Work for Building Construction SSS 1.
Building Construction for Senior Secondary Schools, Book 1.

Instructional Materials

The teacher will teach this lesson with the aid of:

Charts showing different foundation types.
Models of strip, raft, and pile foundations.
Pictures or videos illustrating foundation types on construction sites.
Drawing materials (chalkboard/whiteboard, markers/chalk).

Rationale for the Lesson

This lesson helps pupils understand the basic support systems of buildings. Knowledge of different foundation types is important for building stability and safety, and helps pupils appreciate the role of foundations in construction.

Prerequisite/Previous Knowledge

Pupils are assumed to have a basic understanding of building components and the importance of structural stability in buildings.

Lesson Content/Board Summary

Foundation: Strip, Raft and Pile Types

Definition of Foundation

A foundation is the lowest part of a structure, usually below ground level, which transmits the loads from the building to the soil or rock beneath.

Types of Foundation

Foundations are generally classified into two main types: shallow foundations and deep foundations. The specific types discussed are:

Strip Foundation
Raft Foundation
Pile Foundation

Strip Foundation

A strip foundation is a continuous strip of concrete, wider than the wall it supports, that spreads the load from a wall or a closely spaced row of columns over a larger area of soil.

The basic features of a strip foundation include:

Continuous concrete strip.
Wider than the wall it supports.
Relatively shallow depth.

Situations for using a strip foundation:

When the soil has good bearing capacity.
For light to moderately loaded structures.
When loading is linear, such as under load-bearing walls.

Raft Foundation (Mat Foundation)

A raft foundation is a large concrete slab that extends over the entire footprint of the building, supporting all the walls and columns. It effectively floats the structure on the soil.

The basic features of a raft foundation include:

Large concrete slab covering the entire area.
Distributes load over the whole building area.
Can be flat slab, beam and slab, or cellular type.

Situations for using a raft foundation:

When the soil has low bearing capacity.
When column loads are heavy and closely spaced.
When there is potential for differential settlement.

Pile Foundation

A pile foundation is a deep foundation that transfers loads to deeper, stronger soil or rock strata when the shallow soil is weak or unsuitable. Piles are long, slender members driven or bored into the ground.

The basic features of a pile foundation include:

Long, slender structural elements.
Driven or bored deep into the ground.
Can be concrete, steel, or timber.

Situations for using a pile foundation:

When the upper soil layers are very weak or compressible.
When very heavy loads need to be supported.
When foundations need to resist uplift forces.
In areas with high water tables.

Teaching Methods/Instructional Techniques

Discussion, Lecture, Demonstration, Question and Answer, Visual Aids

Instructional Procedures

Step 1: Introduction

Time: 5 minutes
Teaching Skill: Set Induction
Teacher’s Activity: The teacher greets the pupils, checks attendance, and reviews the previous lesson briefly. The teacher then asks pupils what they think supports a building and introduces the topic of foundations as the lowest part of a building that transfers load to the ground.
Pupils’ Activity: Pupils respond to questions and listen attentively.
Learning Point: Pupils are prepared for the new lesson and relate it to previous knowledge.

Step 2: Definition of Foundation and Types

Time: 10 minutes
Teaching Skill: Explanation/Illustration
Teacher’s Activity: The teacher defines what a foundation is and explains its primary function. The teacher then introduces the three main types of foundations to be studied: strip, raft, and pile foundations, using charts and diagrams to illustrate.
Pupils’ Activity: Pupils listen, take notes, and observe the charts and diagrams.
Learning Point: Pupils understand the definition and general types of foundations.

Step 3: Strip Foundation

Time: 8 minutes
Teaching Skill: Explanation/Demonstration
Teacher’s Activity: The teacher explains strip foundations in detail, describing their basic features and showing models or detailed drawings. The teacher then discusses specific situations where strip foundations are appropriate.
Pupils’ Activity: Pupils listen, ask questions, and make simple sketches in their notebooks.
Learning Point: Pupils understand the features and application of strip foundations.

Step 4: Raft Foundation

Time: 8 minutes
Teaching Skill: Explanation/Comparison
Teacher’s Activity: The teacher explains raft foundations, highlighting their features and how they differ from strip foundations. The teacher presents models or drawings and explains the conditions under which raft foundations are preferred.
Pupils’ Activity: Pupils pay attention, compare the features with strip foundations, and note key information.
Learning Point: Pupils understand the features and application of raft foundations.

Step 5: Pile Foundation

Time: 8 minutes
Teaching Skill: Explanation/Visualisation
Teacher’s Activity: The teacher describes pile foundations, explaining their deep nature and how they transfer loads to stronger ground. The teacher uses diagrams or models to show different types of piles and discusses scenarios requiring pile foundations.
Pupils’ Activity: Pupils listen, visualise the deep foundations, and ask clarifying questions.
Learning Point: Pupils understand the features and application of pile foundations.

Step 6: Class Activity/Discussion

Time: 4 minutes
Teaching Skill: Collaborative Learning
Teacher’s Activity: The teacher guides a short discussion, asking pupils to compare the three foundation types in terms of depth and load distribution. The teacher encourages pupils to think about which foundation type would be suitable for different building scenarios.
Pupils’ Activity: Pupils participate in the discussion, sharing their observations and understanding.
Learning Point: Pupils solidify their understanding through comparison and application.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

Teacher’s Activity: The teacher evaluates the learning by asking the following questions:

Define a foundation.
Mention two types of shallow foundations and one type of deep foundation.
State two basic features of a raft foundation.
Explain one situation where a pile foundation would be necessary.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 2 minutes
Teaching Skill: Summarization
Teacher’s Activity: The teacher summarizes the key points of the lesson, reiterating the importance of foundations in building construction. The teacher then gives pupils an assignment to draw simple sketches of the three foundation types.
Pupils’ Activity: Pupils listen to the summary and copy the assignment.
Learning Point: Pupils consolidate their learning and are given tasks to reinforce understanding.

Lesson Keywords

Foundation – The lowest part of a structure that transmits loads to the ground.
Strip Foundation – A continuous concrete strip supporting walls or closely spaced columns.
Raft Foundation – A large concrete slab covering the entire building area, distributing loads over a wide area.
Pile Foundation – Deep, slender elements driven or bored into the ground to transfer loads to deeper, stronger soil.

Differentiation

For pupils who grasp concepts quickly, the teacher can challenge them to identify local buildings and suggest the likely foundation type used. For pupils needing more support, the teacher can provide simplified diagrams and allow peer-to-peer explanations or provide extra guidance during sketching activities.

Note for teachers using this lesson plan

Ensure that the visual aids (charts, models) are clear and large enough for all pupils to see. Encourage active participation and questions. If a site visit is not feasible, use detailed videos or virtual tours of construction sites to show real-life examples of foundations.