. Application of Cross-Joints

The end of a brick that has the cross-joint applied depends on whether a bricklayer is moving forwards or backwards along the wall as it is built. When moving backwards along the wall, the front end of the brick, as it is held, will have the cross-joint applied. The opposite applies when moving forwards. The latter is slightly more awkward as it is necessary to twist the wrist of the laying hand round in order to apply the mortar joint at the other end of the brick. For this reason, most bricklayers prefer to work backwards along a wall.

To apply a cross-joint, the procedure is as follows:

1. Start with a small scoop of mortar on the end of the trowel. Flick the wrist of the trowel hand slightly but firmly, to cause the mortar to spread across and adhere to the trowel blade.

2. Pick up the brick across its width with the thumb of the laying hand resting on the face side of the brick. Hold the brick and the trowel slightly apart in front of the body in preparation.

. Application of Cross-Joints

Fig. 117 Preparing to apply a cross-joint.

3. Apply the first part of the cross-joint by drawing the trowel blade down across the front edge of the header face, so that a portion of the mortar from the blade is stuck or ‘buttered’ on to the brick. Take care not to smear or stain the face of the brick.

. Application of Cross-Joints

Fig. 118 Applying the first part of the crossjoint.

4. Apply the second part of the cross-joint by reorienting the brick in relation to the trowel and drawing the blade down across the back edge of the header face. Again, a portion of the mortar from the blade should stick on to the brick.

. Application of Cross-Joints

Fig. 119 Applying the second part of the cross-joint.

5. Reorient the brick in relation to the trowel again and draw the blade down across the bottom edge of the header face to complete the cross-joint.

. Application of Cross-Joints

Fig. 120 Completing the cross-joint.

The brick is now ‘buttered’ on the bottom and both side arrises, at its header end, ready for bedding. Sufficient mortar should be used to ensure a full cross-joint when the brick is pressed up to an adjacent brick, since voids will affect the strength of the finished wall. It is not necessary to butter a fourth portion of mortar to the top edge of the header face, as the bed joint of the next course that gets spread over the top will fill it up. Voids in cross-joints create weaknesses in the finished wall, so it is vital to ensure that the three edges are buttered with mortar. In actual fact, the order in which the edges are buttered does not matter, nor does it matter whether the brick is moved in relation to the trowel or vice versa. These are issues of personal style with the only proviso being that the cross-joint must be full and the face of the brick kept clean.

. Application of Cross-Joints

Fig. 121 Laying the next brick.

Cross-joints that are too thick will make bricks difficult to lay against adjacent bricks, with the possibility of the cross-joints ending up too wide. The excess effort required to achieve a 10mm cross-joint could also affect the adjacent brickwork, particularly if the adjacent brick is the ‘quoin brick’ at the end or corner of a wall, which is easily disturbed. The amount of mortar should be sufficient, ideally, for the brick to be pressed into place without the need for the other end of the brick to be tapped with the trowel.