Ching talks about concrete, masonry, stone, and wood. Reading five starts by Ching stating how concrete is made and how reinforcement is required to handle tensile and shear stresses. The mixing of cement and various mineral aggregates with sufficient water to cause the cement to set and blind the entire mass is what customs concrete. Then Ching talks about masonry which he refers to the building with units of various natural or manufactured product, examples are brick, stone, or concrete blocks. 12.07 explains concrete masonry units which are precast of Portland cement, fine aggregate, and water. Concrete masonry is molded into various shapes to satisfy various constructions. Stone is an aggregate or combination of minerals, each of which is composed of inorganic chemical substances. Ching tells us how stones should have the qualities strength, hardness, durability, workability, density, and appearance. 12.11-12.12 was about wood. Wood is mentioned to be as a construction material that’s strong, durable, light and weight, and easy to work with.