1/12: Calculating the size of the bricks

Calculating the size of the bricks

Take 10 random bricks from at least 4 different packs and arrange them lengthwise in a row. Measure the length of the line, divide by the total number of bricks and add an average joint thickness, for example 3 or 4 mm. You use the calculated length as a distribution measure for all the facades. Doublecheck the measurement by repeating the calculation with 10 other bricks.

Calculation example:
The total length of a course of 10 ZERO® bricks is 2040 mm. The average length of a brick is 204 mm. The average brick size is 204 mm + 3.5 mm (average joint thickness) = 207.5 mm. Use this size for calculating what you'll need for the façades.


  • Use the calculated dimensions to make a ruler. You can then use it for the entire construction job, so your stretcher bond will run in a straight course and to avoid the need to grinding into the bricks when finished.
  • Always remove the bricks diagonally from a pack and mix bricks from at least 4 packs.
  • The size of Zero® bricks can differ slightly depending on the production location and production batch. The size of each brick can only be defined with the bricks that are supplied to the site.
  •  If several colours are used in the project, you need to determine the size per brick colour.
  • Don’t use an object to determine the joint (such as a piece of the measure or a small plastic plate). Remember you are working with handmade bricks, which may have individual deviations.
  • You obviously have to take into account the plan when you lay out the bricks further according to the coordinating size. If you were to continue laying out the bricks with ‘fixed weep hole lengths), the Flemish bond would shift and you would have to do a lot of grinding work afterwards.
  • For wall surfaces with a length of less than 5 m, when laying you will not always come out by adapting the head joints within the tolerances. In this case it is necessary to grind bricks.
» Go to tip 2: Calculating the course size