Do Besser blocks need to be reinforced? What are the standard sizes for Besser blocks?

Cornell Engineers' Matt Cornell discusses the use of Besser blocks in residential construction. He explains that concrete masonry #besser block walls must be reinforced with steel reinforcing bars that run vertically and horizontally, and are filled with concrete to increase their strength and stability. The spacing of the bars depends on the purpose of the wall, with #retainingwalls reinforced at 400-millimeter centers and walls of houses reinforced at 1 to 1.4-meter centers. Matt Cornell also states that the standard size of Besser blocks used in #residentialconstruction is the 200 series, which is 190 millimeters thick with a large hollow core for reinforcing and filling with concrete. Other sizes, such as the 150 and 100 series, have less core space. He also mentions that there are other variations and shapes of Besser blocks available for special purposes such as engaged piers and #swimmingpools.

For those of you working in imperial measurements
200 series blocks are 8-inch blocks
150 series blocks are 6-inch blocks
100 series blocks are 4-inch blocks
We use 12mm (half an inch) steel reinforcement for wall reinforcement in retaining walls and the walls of a house. We commonly use 16mm reinforcement in bond beams because most of our Besser block houses are built in cyclonic areas.