Have you ever wondered why house builders do not stack bricks and stones on each other in a straight line, yet it is easier?
In Kenya, most constructors prefer running bonds, a pattern where the first layer of bricks alternates with the second layer. The layers are usually held together with a mixture of cement and sand.
On the other hand, in the stack bond, stones and bricks are directly aligned on top of each other, forming patterns of straight lines vertically.
Why is running bond preferred over stack bond in house construction?
Most housebuilders prefer using running bond because it offers more stability. The fact that the bricks are not aligned and alternate implies that pressure is applied downward hence more stability.
The technology also ensures the wall's stability - two bricks acting as a base for one brick placed on top of it.
Additionally, the running pattern is also preferred because it is one of the easiest patterns to achieve during the construction of a wall.
However, under stack bond, the alignment weakens the walls and can be easily damaged during harsh climates such as strong winds.
Therefore, one is required to support such walls with other materials to avoid them from collapsing.
"Compressive strength is similar for stack and running bond construction. In stack bond masonry, heavy concentrated loads will be carried down to the support by the particular vertical tier or “column” of brick," National Concrete Masonry Association (MCMA) explains on its website.
Nonetheless, most constuctors use this pattern for aesthetic purposes - beautification - as in the case of short walls such as those used in flower gardens or outdoor staircases.
Notably, given the stack bonds appeal more to the eyes, more homeowners use the running bond for the walls, plaster them and then create the stack bond pattern for the exterior.
Despite running and stack bonds being the main patterns used in building construction, other patterns, such as the English bond and flemish garden wall bond, are quite similar to the running bond pattern.