What is the primary purpose of providing weep holes in cavity walls?
- ATo enhance the structural integrity of the wall
- BTo allow trapped water to drain out and prevent moisture buildupCorrect
- CTo improve the thermal insulation of the wall
- DTo provide ventilation to the inner wall cavity
Solution
Concept
Purpose of weep holes in cavity walls
Formula
NONE
Step-by-step solution
1. Weep holes are small drainage/ventilation openings provided in cavity walls. Answer: B
Explanation
Weep holes are small drainage passages constructed at the base of cavity walls to let collected moisture and condensation drain to the exterior. Preventing water accumulation inside the wall cavity protects the structure against dampness and internal water damage. Thus, option B correctly describes their primary purpose.
Why the other options are wrong
A) Weep holes do not increase or affect the structural strength of the wall. C) Thermal insulation is provided by the continuous cavity space, not by weep holes.
Shortcut
Weep holes allow trapped moisture/water inside cavity walls to drain out to the exterior.
Common mistake
Selecting option D by assuming weep holes are primarily designed for cavity wall ventilation rather than liquid water drainage.
Correct answer: B) To allow trapped water to drain out and prevent moisture buildup