Plinth area is calculated for the covered area by taking:
- Aexternal dimensions of the building at the floor levelCorrect
- Binternal dimensions of the building at floor level
- Cboth the external and internal dimension of the building at the floor level
- Dcentre to centre length at floor level
Solution
Concept
Plinth area is the covered built-up area measured using the external dimensions of the building at floor level.
Formula
Plinth area = External length × External breadth (at floor level)
Step-by-step solution
1. Plinth area means the built-up covered area of a building. 2. It is measured at floor level of any storey. 3. External dimensions are used, including wall thickness. 4. Plinth offsets are excluded. 5. So the answer is external dimensions at floor level.
Explanation
Plinth area includes the area of the walls, so outside dimensions are taken. It is measured at floor level, excluding plinth offsets. It is used for plinth area rate estimates.
Why the other options are wrong
B: Internal dimensions give carpet or floor area, not plinth area. C: Plinth area uses only external dimensions, not both. D: Centre-to-centre lengths are used for wall quantities, not plinth area.
Shortcut
Plinth area = outer to outer at floor level.
Common mistake
Confusing plinth area with carpet area, which uses internal dimensions.
Correct answer: A) external dimensions of the building at the floor level