Brick Dimensions: ASTM Standards

A building brick has three dimensions: width or thickness, height, and length. The height and length of brick are sometimes called face dimensions, as these are the dimensions that are exposed when the brick is laid as a stretcher as shown in the figure-2.

Fig.1. Brick Dimensions

Fig.2. Brick Positions in Wall

When coming to the designation of brick dimensions, there are mainly three sets of dimensions used with brick. They are:

1. Nominal dimension 
2. Specified dimension
3. Actual dimension

1. Nominal Dimension of Bricks

Nominal dimensions are final dimensions of brick that include the dimension of the brick plus the intended thickness of its intended mortar joint. These dimensions are specified in round numbers, for example, 4 or 8 inches in imperial units or 100 mm in SI units. This is a quick way to refer to a brick size without including fractions. These dimensions are mainly employed for modular bricks.

2. Specified Dimensions of Bricks

Specified dimensions of bricks are anticipated manufactured dimensions of brick excluding the width of the mortar joint. These dimensions are mainly used for project specifications and purchase orders. It is also used for the rational design of brick masonry. These dimensions are commonly used in non-modular construction.

Fig.3. Nominal and Specific Dimensions of Modular Bricks

3. Actual Dimensions of Bricks

Actual dimensions of bricks are the measurements of the bricks as manufactured. These dimensions will be within a tolerance of the specified dimensions. The tolerances are dependent on the type and size of the bricks are given within ASTM standard specifications.

Also Read: 

Different Grades of Solid Bricks - ASTM Standard C62-99

Classification of Bricks -ASTM Standards