Some useful guidelines for constructing parapet wall
Parapet wall stands for a protection wall that can resist the collapsing from terrace to ground. Different types of parapet walls are found which range from brick wall masonry parapet wall, wooden handrail, iron grill etc.
Size of parapet wall:
1. Thickness of parapet wall should be minimum 9''. (full brick parapet wall)
2. Half brick parapet wall is not recommended for use.
3. Height of the parapet should be minimum 3'0''.
Once the centering and shuttering from roof slab bottom is detached, some deflection may happen at mid span of roof slab (positive bending moment). Similar thing will happen at support like negative bending moment.
With a view to prevent negative bending moment at support, huge amount of loads are required as downwards. In case of constructing the parapet wall as half brick wall, the roof can’t be prevented from uplifting. If the parapet wall is constructed as minimum 9'' thickness and minimum 3'0'' height, the roof slab can be prevented from uplifting. Therefore, different types of cracks at bottom of ceiling will be captured. To get rid of uplifting of roof, the centering & shuttering should be eliminated once the entire full brick parapet wall is constructed.
If the first floor is extended in future, the existing parapet wall should not be dismantled in case the wall is constructed as 9'' thick.
Assume, the parapet wall is constructed as half brick wall, now it is required to demolish the current parapet wall up to roof and make it as 9'', therefore, extra money will be incurred up to sill level of first floor.
While erecting half brick parapet wall, brick pillars should be arranged at regular interval ( 5 to 6 feet). Inner surface of parapet wall does not include flat surface since lots of offset will be created. Therefore, some problems will arise in waterline and sanitary plumping works.
Water from pump and discharge from water tank will be influenced with various offset produced with half brick parapet wall.
No tie exists for half brick parapet wall. As a result, wind pressure may provide some effects. Sliding of parapet wall may also happen.
If the column height is terminated for the height of the parapet wall (3 feet), it is required to dismantle for overlapping in future first floor construction. Adjacent Brick parapet wall will also be affected. If the height of parapet wall remains 3 feet, the column height should be increased for extra height for future overlapping. Then the column and parapet wall will be protected from over damaged.
It is recommended to construct full brick parapet wall for minimum height of 3 feet devoid of half brick parapet wall.
There should be some provision for column for future overlapping.