Correct Answer - Option 1 : 15 to 20 mm
Concept:
Pointing is generally adopted for the finishing of exposed external walls of a structure.
The Different types of pointing are given in the following table:
| S. No. |
Details of different types of pointing |
| Type of pointing |
Details |
| 1 |
Flush |
The mortar is pressed hard in the raked joints and by finishing off flush with the edge of masonry units. The edges are neatly trimmed with a trowel and straight edge. It does not give a good appearance. |
| 2 |
Recessed |
The mortar is pressing back by 5mm or more from the edges. During the placing of mortar, the face of the pointing is kept vertical, by a suitable tool. This type gives a very good appearance. |
| 3 |
Beaded |
It is formed by steel or ironed with a concave edge. It gives a good appearance, but it will damage easily when compared to other types. |
| 4 |
Struck |
This is a modification of flush pointing in which the face the pointing is kept inclined, with its upper edge pressed inside the face by 10mm which drains water easily. |
| 5 |
Rubbed, Keyed, or Grooved Pointing
|
This is also a modification of flush pointing in which a groove is formed at its mid-height, by a pointing tool. It gives a good appearance. |
| 6 |
Truck |
In this case, mortar is pressed in the raked joint first and finishes flush with the face. While the pressed mortar is green, a groove or narrow channel is cut in the center of the groove which is having 5mm width and 3mm depth. |
| 7 |
V- Pointing |
This is formed by forming V - groove in the flush-finishing face.
|
| 8 |
Weathered
|
This is made by making a projection in the form of a V-shape. |
Explanation:
-
Finishing of mortar points of either stone masonry or brick masonry is called pointing.
- In exposed masonry, joints are considered to be the weakest and most vulnerable spots from which rainwater or dampness can enter.
- Pointing consists of raking the points to a depth of 10 to 20 mm and filling them off with better quality mortar in the desired shape.
