Basics in Building Construction

Basics in Building Construction 4(2+2)

Lesson 12 and 13: Basic Building Construction Materials

Building Stones

Rocks form the sources of stones. Rocks are available in nature. Depending on the type of formation rocks are sub-divided as

1. Igneous Rocks

   These rocks are formed due to the cooling of the molten earth i.e. Magma. Due to high temperatures at depths the earth melts and comes out occasionally. This molten earth when exposed to the weather cools down slowly and forms as rocks. These rocks are hard, closely grained, have good texture, strong and durable. Traps, Granite, Basalt are some of the examples of igneous rocks.

2. Sedimentary rocks

   These rocks are formed due to deposition of weathered particles of igneous rocks. Natural agents like wind, rain, frost etc. carry away these particles from its origin and deposit somewhere else. These rocks possess less strength. Lime stone, Gypsum, Chalk etc. are some of the examples of sedimentary rocks.

3. Metamorphic rocks

   Due to change in their physical and chemical properties under intensive heat and pressure, igneous rocks and sedimentary rocks are converted into metamorphic rocks. Marble, Gniess, Laterite, Quartzite, Slate are some of the examples of meta­morphic rocks.

Commonly Used Building Stones