Class: Senior Secondary School 1 (SS1, SS 1, SSS1, SSS 1)
Term: 3rd Term
Week: 8
Age: 15 years
Duration: 45 minutes
Subject: Building Construction
Curriculum Theme: Building Construction
Previous Lesson: Practical on Bonding: Stretcher, Header, Flemish and English Bonds.
Topic: Drainage System: Meaning, Terms and Types
Subject Matter: definition of drainage, terms used in drainage works, principles of drainage, types of drainage systems, sketching and describing simple drainage layouts

Specific Objectives

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

Cognitive Domain:

Define drainage.
State at least five terms used in drainage works.
Explain at least three principles of drainage.
Identify and describe two types of drainage systems.

Affective Domain:

Appreciate the importance of proper drainage in buildings.
Participate actively in class discussions.

Psychomotor Domain:

Sketch a simple drainage layout.
Label parts of a simple drainage layout.

Work collaboratively during group activities.

Reference Materials

The following resources were used in planning this lesson:

9 Years Basic Education Curriculum for Building Construction (Senior Secondary School).
State Unified Scheme of Work for Building Construction.
Building Construction for Senior Secondary Schools by N.A. Ajayi.
Building Construction: A Practical Guide for Students by R. Barry.

Instructional Materials

The teacher will teach this lesson with the aid of:

Whiteboard and markers.
PVC pipes and fittings (samples).
Charts showing sample drainage layouts.
Diagrams of drainage components (e.g., traps, manholes).

Rationale for the Lesson

Understanding drainage systems is important for pupils to appreciate how waste water is removed from buildings. This knowledge helps them to recognize the components and principles that ensure healthy and hygienic living environments in their homes and communities.

Prerequisite/Previous Knowledge

Pupils should have basic knowledge of building components and the importance of sanitation from their previous lessons.

Lesson Content/Board Summary

Drainage System: Meaning, Terms and Types

Meaning of Drainage

Drainage refers to the system or process by which water or liquid waste is removed from a building or an area. It involves the collection, conveyance, and disposal of wastewater, stormwater, or groundwater.

Terms Used in Drainage Works

The following are common terms used in drainage works:

Waste Pipe: A pipe that conveys wastewater from appliances (e.g., sinks, baths) but not from water closets.
Soil Pipe: A pipe that conveys discharge from water closets and may also convey wastewater from other appliances.
Vent Pipe: A pipe connected to a drainage system to provide ventilation and prevent the loss of water seals in traps.
Trap: A device that holds a small quantity of water to form a seal, preventing foul air from the drainage system entering the building.
Gulley: An open receptacle with a trap, usually located outside a building, to receive wastewater from waste pipes before discharging into the drain.
Manhole/Inspection Chamber: An access chamber built into a drain or sewer line to allow for inspection, cleaning, and maintenance.
Drain: A pipe that carries wastewater or stormwater from a building to a sewer or treatment plant.
Sewer: A large underground pipe that carries wastewater and sometimes stormwater from multiple drains to a treatment plant or disposal point.

Principles of Drainage

The following are important principles that guide the design and installation of an effective drainage system:

Adequate Fall/Gradient: Drains must be laid with a sufficient slope to ensure self-cleansing velocity of the wastewater, preventing solids from settling.
Proper Ventilation: The drainage system must be adequately ventilated to prevent the build-up of foul gases and to protect water seals in traps.
Effective Water Seals: All sanitary fittings must be provided with traps that maintain a water seal to prevent the entry of foul air into the building.
Accessibility for Cleaning: The system should include inspection chambers or manholes at changes in direction, gradient, or pipe size to allow for easy access for cleaning and maintenance.
Durable and Impermeable Materials: Drainage pipes and fittings must be made of strong, non-absorbent, and corrosion-resistant materials to prevent leakage and ensure longevity.
Air Tightness and Water Tightness: The entire system must be airtight and watertight to prevent leakage of wastewater and the escape of foul air.

Types of Drainage Systems

The following are common types of drainage systems:

Combined System: This system uses a single set of pipes (drains and sewers) to carry both foul wastewater (from toilets, sinks) and stormwater (rainwater) together.
Separate System: This system uses two separate sets of pipes. One set carries foul wastewater, and the other set carries stormwater. This allows for different treatment methods for each type of water.
Partially Separate System: This system is a hybrid where foul wastewater is carried in one set of pipes, and stormwater from roofs is discharged into the foul water sewer, while stormwater from yards and roads is carried in a separate system.

Sketching and Describing Simple Drainage Layouts

A drainage layout is a diagrammatic representation showing the arrangement of pipes, fittings, and components of a drainage system within and around a building. It indicates the flow path of wastewater from sanitary fittings to the main sewer or disposal point, including the location of traps, inspection chambers, and manholes.

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 what happens to water after it is used in the toilet, bathroom, or kitchen. The teacher listens to their responses and guides them towards the concept of drainage.
Pupils’ Activity: Pupils respond to the teacher’s questions, sharing their ideas about wastewater disposal.
Learning Point: Pupils recall prior knowledge and are introduced to the lesson topic.

Step 2: Definition of Drainage

Time: 5 minutes
Teaching Skill: Explanation/Definition
Teacher’s Activity: The teacher defines drainage as the system for removing wastewater from buildings and writes the definition on the board.
Pupils’ Activity: Pupils listen attentively and copy the definition into their notebooks.
Learning Point: Pupils learn the meaning of drainage.

Step 3: Terms Used in Drainage Works

Time: 10 minutes
Teaching Skill: Explanation/Listing
Teacher’s Activity: The teacher introduces and explains various terms used in drainage works such as waste pipe, soil pipe, vent pipe, trap, gulley, manhole, and drain, using charts and actual samples (PVC pipes/fittings) where possible.
Pupils’ Activity: Pupils observe the materials, listen to the explanations, and ask questions for clarification. They note down the terms and their definitions.
Learning Point: Pupils identify and understand key terminology related to drainage systems.

Step 4: Principles of Drainage

Time: 7 minutes
Teaching Skill: Explanation/Discussion
Teacher’s Activity: The teacher explains the fundamental principles of good drainage, such as adequate fall, proper ventilation, and accessibility for cleaning, using simple examples.
Pupils’ Activity: Pupils listen and engage in a brief discussion on why these principles are important for an effective drainage system.
Learning Point: Pupils understand the guiding principles for effective drainage system design.

Step 5: Types of Drainage Systems

Time: 7 minutes
Teaching Skill: Classification/Explanation
Teacher’s Activity: The teacher describes the different types of drainage systems: combined, separate, and partially separate systems, highlighting their key differences and applications.
Pupils’ Activity: Pupils listen, take notes, and ask questions to differentiate between the various systems.
Learning Point: Pupils learn to identify and describe the main types of drainage systems.

Step 6: Sketching and Describing Simple Drainage Layouts

Time: 5 minutes
Teaching Skill: Demonstration/Visualisation
Teacher’s Activity: The teacher uses a chart or sketches a simple drainage layout on the board, explaining what it represents and how it helps in understanding the flow of wastewater. Pupils are encouraged to attempt a simple sketch.
Pupils’ Activity: Pupils observe the sketch, listen to the description, and attempt to draw a simple layout in their notebooks.
Learning Point: Pupils develop basic skills in interpreting and sketching drainage layouts.

Step 7: Evaluation/Review

Time: 5 minutes

Teaching Skill: Questioning/Assessment

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

What is drainage?
Mention three terms used in drainage works.
State two important principles of drainage.
List two types of drainage systems.

Pupils’ Activity: Pupils answer orally and in writing.

Learning Point: Pupils demonstrate understanding of the lesson.

Step 8: Conclusion

Time: 1 minute
Teaching Skill: Summarization
Teacher’s Activity: The teacher summarizes the key points of the lesson, emphasizing the importance of proper drainage for hygiene and health. The teacher then gives pupils a take-home assignment to draw a simple drainage layout of their home.
Pupils’ Activity: Pupils listen to the summary and copy down the assignment.
Learning Point: Pupils consolidate their learning and are given an opportunity for further practice.

Lesson Keywords

Drainage – The system or process by which water or liquid waste is removed from a building or an area.
Waste Pipe – A pipe that carries wastewater from appliances other than water closets.
Soil Pipe – A pipe that carries discharge from water closets and other sanitary fittings.
Trap – A device that maintains a water seal to prevent foul air from entering a building.
Manhole – An access chamber for inspection and cleaning of drains and sewers.
Sewer – A large underground pipe carrying wastewater from multiple properties.
Fall/Gradient – The slope given to a drain to ensure effective flow of wastewater.

Differentiation

For pupils who grasp concepts quickly, the teacher can provide additional questions on the advantages and disadvantages of different drainage systems. For pupils who require more support, the teacher can provide simplified diagrams and allow for peer tutoring during the sketching activity.

Note for teachers using this lesson plan

Teachers should ensure that visual aids, such as charts of drainage layouts and actual pipe samples, are available to enhance understanding. Encourage pupils to relate the concepts to their immediate environment. Emphasize safety precautions if handling actual drainage materials. Ensure all pupils participate in the sketching activity, providing individual feedback.