Building the First Course
Having set-out, always start every course with the quoin (corner) brick, which is laid to gauge, level and plumb (see Fig 132, A). Assuming the edges and faces of the brick to be reasonably square, plumbing the stretcher face of the quoin brick is sufficient to provide the level across the width of the brick without actually levelling it! If the bedding face and stretcher face are slightly out of square with one another, the deviation will be small and not show too much in the short bed joint along the header face. Instead of plumbing the header face of the end or quoin brick, always level along its length and then plumb up by simply adjusting the brick until the header face, at least in part, touches the level. This method is adopted because, if the bedding face and header face of the brick are slightly out of square with one another, plumbing the header face would cause a large deviation in the long bed joint along the stretcher face.
When laying end or quoin bricks, the general rule is to plumb up the stretcher face and accept the resultant level across the width. Then the brick is levelled along its length and the resultant plumb up the header face accepted, subject to making sure the header face touches the level for plumb. Where bricks are reasonably square, this rule provides the best balance between plumb and level at a corner or end of a wall and allows for small variances in brick shape/dimensions. The only exception to this rule relates to the very first quoin brick in the first course in a new wall, which is often levelled across length and width due to the practical difficulty in plumbing up the stretcher face of one brick (only a height of 65mm), since trying to hold the level against one brick often disturbs it!
Next, construct the ‘arms’ of the corner (maximum of three or four stretchers long) by laying bricks, to the setting-out line, outwards from the quoin brick then levelling them along their length (see Fig 132, B and C). As this is the very first course of the wall, the bricks should be checked for level across their width to ensure that they are not ‘tipping’ over. When laying straight out from the quoin brick, care must be taken to ensure that cross-joints are of the correct thickness; if necessary, a measuring tape should be used to check the lengths of the arms. The figures in this example will be 665mm (three bricks long including 10mm joints) and 778mm (three and a half bricks long including joints).
Once the first course has been completed, it must be checked for square with a builder’s square, and the spirit level should be used as a straight-edge to get both sides in line and straight (see Fig 132, D).