Question 4
(a) State three functional requirements of a roof.
(b) Use a sketch to illustrate the method of fastening a roof rafter to the ring beam.
(c) List three materials used for the manufacture of drain pipes.
Observation
Most candidates were able to:
- State three functional requirements of a roof.
- List three materials used for the manufacture of drain pipes.
However, some of them failed touse a sketch to illustrate the method of fastening a roof rafter to the ring beam.
The expected response to question 4 is as given below:
4. (a) Functional Requirements of A Roof
- Strength
- Durability
- Exclusion of wind and rain
- Resistance to spread of fire
- Resistance to heat
- Stability
- Resistance to sound penetration
- Resistance to leakage of air
- Security
- Aesthetics
(b) A Sketch illustrating the Method of Fastening a Roof Rafter to the wall
(c) Materials used for Making Drain Pipes
- Pitch-fibre
- Vitrified clay
- Polyvinyl Chloride (P.V.C)
- Cast-iron
- Asbestos cement
- Concrete