Class: Senior Secondary School 2 (SS2 / SSS2)
Term: 3rd Term
Week: 3
Age: 16 years
Duration: 45 minutes
Subject: Building Construction
Curriculum Theme: Building Elements
Previous Lesson: Roofs: Definition and purpose of roof, Roof.
Topic: ROOFS
Subject Matter: Functional requirement of roof (protection, drainage, durability), Materials used for roof construction (roofing sheets, nails, 2×2 timber, 2×4 timber) (materials identification)

Specific Objectives

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

Cognitive Domain:

Define a roof.
State at least three functional requirements of a roof.
Identify and list common materials used for roof construction.

Affective Domain:

Appreciate the importance of roofs in protecting buildings.
Show interest in the different types of roofing materials.

Psychomotor Domain:

Sketch a simple roof diagram.
Identify actual roofing materials when presented.

Participate actively in discussions about roof construction.

Reference Materials

The following resources were used in planning this lesson:

Senior Secondary Schools Education Curriculum
State Unified Scheme of Work
Oyebode, F. (2018). Building Construction for Senior Secondary Schools. Lagos: Macmillan Nigeria Publishers.
https://www.designingbuildings.co.uk/wiki/Functional_requirements_of_a_roof
https://www.theconstructor.org/building/roof-materials-types-advantages-disadvantages/1592/

Instructional Materials

The teacher will teach this lesson with the aid of:

Charts showing different roof types and components.
Samples of roofing sheets (e.g., aluminium, corrugated iron).
Samples of nails (e.g., roofing nails).
Samples of timber (e.g., 2×2, 2×4).
Diagrams of various roof structures.

Rationale for the Lesson

This lesson helps pupils understand the essential role of roofs in building construction. It enables them to identify the key functions of a roof and the materials used, which is fundamental knowledge for future building professionals and for appreciating safe housing.

Prerequisite/Previous Knowledge

Pupils should have basic knowledge of building components and the different parts of a house.

Lesson Content/Board Summary

ROOFS

Definition of a Roof

A roof is the upper covering of a building, designed to provide protection from weather elements such as rain, sun, wind, and snow. It forms an essential part of the building envelope, contributing to the structural integrity and aesthetic appeal of the building.

Functional Requirements of a Roof

A roof must perform several functions to ensure the safety, comfort, and durability of a building. These include:

Protection: A primary function of a roof is to protect the interior of the building and its occupants from environmental factors like rain, sun, wind, and extreme temperatures.
Drainage: Roofs are designed with slopes to effectively drain rainwater and prevent ponding, which can lead to leaks and structural damage. Gutters and downpipes assist in directing water away from the building.
Durability: A roof must be constructed from materials that can withstand weather conditions, resist decay, and last for a long period without requiring frequent repairs or replacement.
Thermal Insulation: Roofs help to regulate the internal temperature of a building by preventing excessive heat gain in hot weather and heat loss in cold weather.
Sound Insulation: They also provide a degree of sound insulation, reducing noise from external sources such as rain, wind, and traffic.
Security: A roof contributes to the overall security of a building by preventing unauthorized access.
Aesthetics: The design and material of a roof add to the visual appeal and architectural style of a building.

Components of a Roof

The main structural components that make up a typical timber roof include:

Rafters: Sloping members that support the roof covering.
Ridge Board: The horizontal timber at the apex of the roof, where the rafters meet.
Purlins: Horizontal timbers that support rafters or roof covering between trusses or main rafters.
Wall Plate: Timber fixed to the top of the wall to which the feet of the rafters are secured.
Eaves: The part of the roof that overhangs the walls.
Fascia Board: A board fixed horizontally to the ends of the rafters at the eaves.
Soffit: The underside of the eaves.

Materials Used for Roof Construction

Various materials are used in roof construction, each offering different characteristics in terms of durability, cost, and aesthetics. Common materials include:

Roofing Sheets:
- Aluminium Sheets: Lightweight, durable, rust-resistant, and come in various colours.
- Corrugated Iron Sheets: Economical, strong, and widely used, often galvanized for rust protection.
- Asbestos Cement Sheets: Once common but now phased out in many places due to health concerns.
- Plastic/PVC Sheets: Lightweight, transparent or translucent, used for skylights or patios.
Nails:
- Roofing Nails: Specifically designed with larger heads and often galvanized for weather resistance, used to secure roofing sheets.
- Common Nails: Used for general timber framing.
Timber: Used for the structural framework of the roof. Common sizes include:
- 2×2 Timber (50mm x 50mm): Used for battens or lighter support.
- 2×4 Timber (50mm x 100mm): Commonly used for rafters, purlins, and other structural members.
- Other sizes like 2×3, 2×6, 2×8 are also used depending on span and load requirements.
Other Materials: Cement, sand (for mortar in concrete roofs), roofing felt, sealants, gutters, and downpipes.

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 and asks them to identify the part of the school building that protects them from rain and sun. The teacher then introduces the topic: ROOFS.
Pupils’ Activity: Pupils respond by identifying the roof and listen attentively to the introduction.
Learning Point: Pupils are introduced to the topic and its relevance.

Step 2: Definition and Purpose of Roof

Time: 7 minutes
Teaching Skill: Explanation/Discussion
Teacher’s Activity: The teacher defines a roof and explains its general purpose as the upper covering of a building. The teacher writes the definition on the board.
Pupils’ Activity: Pupils listen, contribute to the discussion, and copy the definition into their notebooks.
Learning Point: Pupils understand the basic definition and purpose of a roof.

Step 3: Functional Requirements of a Roof

Time: 7 minutes
Teaching Skill: Explanation/Listing
Teacher’s Activity: The teacher explains the functional requirements of a roof, focusing on protection, drainage, and durability, and elaborating on others like thermal and sound insulation. The teacher lists these points on the board.
Pupils’ Activity: Pupils listen, ask questions for clarity, and take notes.
Learning Point: Pupils learn the specific functions a roof must perform.

Step 4: Components of a Roof

Time: 7 minutes
Teaching Skill: Illustration/Identification
Teacher’s Activity: The teacher uses charts and diagrams to show and explain the various components of a roof structure, such as rafters, ridge board, purlins, and eaves. The teacher identifies each component.
Pupils’ Activity: Pupils observe the diagrams, ask questions, and identify the components as explained.
Learning Point: Pupils can identify the structural parts of a roof.

Step 5: Materials Used for Roof Construction

Time: 7 minutes
Teaching Skill: Demonstration/Identification
Teacher’s Activity: The teacher presents samples of roofing sheets (aluminium, corrugated iron), nails, and timber (2×2, 2×4). The teacher discusses the characteristics and uses of each material. The teacher lists these materials on the board.
Pupils’ Activity: Pupils observe the materials, handle them carefully, and note their properties and uses.
Learning Point: Pupils identify and understand the purpose of different roofing materials.

Step 6: Drawing and Practical Identification

Time: 5 minutes
Teaching Skill: Practical Application
Teacher’s Activity: The teacher draws a simple sketch of a roof structure on the board, labeling key components. The teacher asks pupils to identify the presented materials again.
Pupils’ Activity: Pupils attempt to sketch the roof diagram and correctly identify the roofing materials.
Learning Point: Pupils develop practical identification and drawing skills related to roofs.

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 roof.
State three functional requirements of a roof.
Mention two common materials used for roof covering.
List two types of timber used in roof construction.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 2 minutes
Teacher’s Activity: The teacher summarizes the key points of the lesson, emphasizing the importance of a well-constructed roof. The teacher gives pupils an assignment to draw and label a simple gable roof.
Pupils’ Activity: Pupils listen to the summary and copy the assignment.
Learning Point: The lesson is concluded, and pupils receive an assignment to reinforce learning.

Lesson Keywords

Roof – The upper covering of a building.
Functional requirements – The essential purposes a roof must fulfill.
Protection – Shielding from weather elements.
Drainage – The process of removing water from the roof surface.
Durability – The ability of a roof to withstand wear, pressure, or damage over time.
Roofing sheets – Pre-formed panels used as the outer covering of a roof.
Timber – Wood used for structural framing in construction.
Rafters – Sloping structural members that support the roof covering.

Differentiation

For pupils who grasp concepts quickly, the teacher can encourage them to research different roof types (e.g., hip, lean-to) and their specific components. For pupils needing more support, the teacher will provide simplified diagrams and allow more time for practical identification of materials.

Note for teachers using this lesson plan

Teachers should ensure that actual samples of roofing materials are available for pupils to see and touch. Encourage active participation and drawing during the lesson. Emphasize safety aspects related to roof construction and materials.