In this reading Ching talks about Materials and properties. Stone is made up of 6 things strength, hardness, durability, workability, density and appearance. Stone can also be used in different forms flagstone, crushed stone, and dimension stone. Ching also talks about masonry. Brick is masonry unit of clay formed into a rectangular prism. There are different type of brick like FBX, FBS, FBA, which vary in size and color for different occasions. There are also concrete masonry (CMU) there cement blocks are really strong. They have a compressive strength of 600 to 1500 psi. Theres also different weight for example normal weight block is more than 2000kg, medium weight block is from 1680 to 2000 kg and lightweight would be 1680 or less. Ching also talks about wood. Wood is strong durable and light in weight. there are soft wood and hard wood which are the two major classes of wood. typically a piece of wood will with stand 1/3 more force then parallel to its grain. One major thing about would is that it has shrinkage if it has moisture it can expand unto 30 percent but ones is looses moisture it shrinks . this is vary important and must be taken into consideration once applying. Wood also has things like knots, shakes, checks, pitch pockets, and wane which also play a big part once applying. In addition Ching discusses steel. steel is any iron based alloys there are different shapes they come in. There are W shape, S shapes, C shapes, L shapes, and WT shape. The S shapes and C shapes are American Standard use. Almost all the building around us are made up of steel its really strong and durable. Concrete is made of three important components cement want aggregate. aggregate is basically little peaces of rock, sand , minerals. These things mixed together can make you a solid peace of concrete. The cement should also be in motion or else it would become a solid. This is why the trucks have the back part rotating as they go on to the site. The cement is always tested. Cement its take into a lab and poured onto a cone shaped container and flipped . They let it sit to see the reaction of the cement if its to much of a liquid it bad if it hardened to fast its also bad it should be just the right amount.