Most builder’s profiles require the first three courses of the wall to be built before they can be used, so it can be attached to the wall base. These first three courses are very important because if they are not plumb, level and square, the profile itself will not be and the whole wall will be built unevenly.
How to make them square
Before laying your first course, you need to mark out the boundaries of your wall and, if you have a corner, make sure that it is an accurate right angle. To get a right angle use the 3, 4, 5 rule.
The 3, 4, 5 rule:
From one side of a corner, mark out a measurement of three (3ft, 3m, 3cm etc). On the opposite corner, mark out a measurement of four (4ft, 4m,4cm etc). Finally, measure the distance between the three and four marks and if the distance is five (5ft, 5m, 5cm etc) the corner is square (90°).
Step 1 – Mark corner
Place a brick or mark where the corner will be.
Step 2 – Mark out edges
Mark out where the two edges or other two corners will be and place down another brick.
Step 3 – Make a measurement of three
Using the 3, 4, 5 rule check your corner is a right angle. Measure out from the first corner a measurement of 3 (3ft, 3m etc).
From the other side of the corner, measure out a distance of 4 (4ft, 4m etc).
Next, measure the distance between these two points if it is a measurement of 5 (5ft, 5m etc) then you have a right angle, if not, adjust accordingly.
If you are building a large wall, it may be more beneficial to use the 3, 4, 5 rule in a multiple of two. For example, measure out two marks of 6 (6ft, 6m etc) and 8 (8ft, 8m etc) and find the distance between as 10 (10ft, 10m). Using a multiple of ten also works, for example 300 (cm, m, in) and 400 (cm, m, in) to find the distance 500 (cm, m in) in between.
Lay the first course
Step 1 – Dampen bricks
To lay the first course, use a spirit level with every brick to make sure it is plumb and level. Make sure the bricks have been dampened before you use them; if the bricks are dry they will suck the moisture out of the mortar and this will weaken your joints.
Step 2 – Lay mortar
Lay a bed of mortar onto the foundations, about 10mm (0.4in) thick.
Step 3 – Start second course
Lay the bricks out from the corner using a spirit level to make sure they are plumb and level. For the second course, start your corner brick in the opposite direction to your first course.
Step 4 – Build up second and third courses
Build the second and third courses up, continuing to use the spirit level to ensure they are accurately in line.
Once the third course has been built and left to set overnight, your builder’s profile can be set up.