Following procedure is followed to perform the pointing work:
- The existing mortar joint is raked out at least to a depth of 20 mm.
- The joint is perfectly cleaned by using a brush.
- The mortar joint is made wet by washing with clean water and kept wet for a few hours.
- Over the prepared joint the mortar is carefully placed in the desired shape. For this purpose a small trowel is used and the mortar is pressed and brought into close contact with the old interior mortar of the joint.
- For at least three days, the finished surface is well-watered if lime mortar is used and ten days if cement mortar is used.
26.3.3 Types of Pointing
Different types of pointing are in use. The choice of a particular type of pointing depends on the type of masonry and the effect required. Usual types of pointing are explained below.
1. Flush Pointing
This type of pointing is formed by removing the excess mortar from the joint and made flush with the surface of the wall (Fig. 26.6). Although it does not give a pleasant appearance, it is durable and does not give any room for accumulation of dust. Thus it has large usage.
Figure 26.6 Flush pointing
2. Recessed Pointing
This joint is also has a vertical face as that of flush pointing, but pressed inside the wall surface using a special tool to a length of about 5 mm or more. This gives a very good appearance (Fig. 26.7).
Figure 26.7 Recessed pointing
3. Beaded Pointing
This is a special type of pointing having a good appearance because of the beading point. This type is made using a steel or iron rod with a concave edge. This type of pointing is difficult to maintain (Fig. 26.8).
Figure 26.8 Beaded pointing
4. Rubbed Pointing
This type of pointing is also called as keyed or grooved pointing. Here a groove is made at the centre of height by a pointer. This type of pointing is generally adopted as it is easy to make and gives good appearance (Fig. 26.9).
Figure 26.9 Rubbed pointing
5. Struck Pointing
In this type the face of the pointing is made inclined (Fig. 26.10) downwards. The upper edge of joint is at about 10 mm inside the wall surface and the lower edge is kept just inside the face of masonry. It is not a common type as water can get collected.
6. Tuck Pointing
In this type of pointing, a groove is cut at the centre of the mortar joint of 5 mm width and 3 mm depth. This groove is then filled with white cement putty with a projection of 3 mm (Fig. 26.11). If the projection is done in the mortar, is called half tuck pointing.
Figure 26.10 Struck pointing
Figure 26.11 Tuck pointing
7. Vee-pointing
In this type of pointing a V-shaped groove is formed in the mortar joint (Fig. 26.12).
Figure 26.12 Vee-pointing
8. Weathered Pointing
In this type of pointing a V-shaped projection is made as shown in Fig. 26.13.
Figure 26.13 Weathered pointing
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