If you ever have to construct a new wall there are 3 options – 3 types of bricks. Clay brick, Solid concrete block and Fly Ash bricks ( popularly called as Siporex bricks.
1) Clay brick is made from mud and is made in bhatti (Big oven). Two common size (width ) of Red clay bricks are – 4 inch and 6 inch. When compared to other types bricks – it absorbs maximum amount of water. It does not get dry and when POP or plaster is done on it, the water comes out toward it. So it is important that brick is properly burned.
2) Solid blocks are made from pressure steam curing. They are almost like a block of concrete. Very heavy in weight. Not recommend for internal walls.
3) Siporex ( fly ash brick ) is made from silica. They are very light in weight. Easily available in market in different sizes: 2, 4 and 6 inch thick. If you are planning to construct or move wall, siporex is excellent option to go for. It is costlier option compared to other two, but it will make your wall light in weight & still of same strength.