Brick (clay)

Uses - Walls, paths, driveways

Advantages - Versatile, good thermal mass
Disadvantages - Production is energy-intensive and uses non-renewable resources.
Earth-wise tips - Look for recycled bricks.

Concrete

Uses - Floors, walls, supports

Advantages - High thermal mass, strong, durable, economical, resists termites and earthquakes

Disadvantages - Production involves quarrying and creates greenhouse emissions; poor insulator, needs reinforcing.
Earth-wise tips - Use autoclaved aerated concrete (AAC), which is lightweight, energy-efficient and non-toxic, or concrete made with recycled aggregate.

 

Cement: In the most general sense of the word, a cement is a binder, a substance that sets and hardens independently, and can bind other materials together. Cement used in construction is characterized as hydraulic or non-hydraulic. Hydraulic cements (e.g., Portland cement) harden because of hydration, chemical reactions that occur independently of the mixture's water content; they can harden even underwater or when constantly exposed to wet weather. The chemical reaction that results when the anhydrous cement powder is mixed with water produces hydrates that are not water-soluble. Non-hydraulic cements (e.g., lime and gypsum plaster) must be kept dry in order to retain their strength.

Cement is made by heating limestone (calcium carbonate) with small quantities of other materials (such as clay) to 1450 °C in a kiln, in a process known as calcination, whereby a molecule of carbon dioxide is liberated from the calcium carbonate to form calcium oxide, or quicklime, which is then blended with the other materials that have been included in the mix. The resulting hard substance, called 'clinker', is then ground with a small amount of gypsum into a powder to make 'Ordinary Portland Cement', the most commonly used type of cement (often referred to as OPC).

Ordinary Portland Cement (OPC) is manufactured in the form of different grades, the most common in India being Grade-53, Grade-43, and Grade-33. Ordinary Portland Cement-Grade 43 is largely used for residential, commercial, and other building construction purposes. It has a compressive strength of 560 kg per square cm.

Ordinary Portland Cement-Grade 53 is known for its rich quality and is highly durable. Hence it is used for constructing bigger structures like building foundations, bridges, tall buildings, and structures designed to withstand heavy pressure.

Portland cement is a basic ingredient of concrete, mortar and most non-speciality grout. The most common use for Portland cement is in the production of concrete. Portland cement may be grey or white.

The

Steel

Uses - Frames, supports
Advantages - Strong, economical, durable, recyclable

Disadvantages - Production is energy-intensive and highly polluting; coatings are often polluting.

Earth-wise tips - Buy recycled steel or opt for renewable timber.

Stone and composite stone

Uses - Walls, floors, supports
Advantages - Abundant, durable, high thermal mass, economical if available on site; no toxic emissions
Disadvantages - Non-renewable; extraction and transportation can be energy-intensive.

Earth-wise tips - Use salvaged stone or products made with waste stone from local sources.

Timber

Uses  - Floors, walls, supports and roof frames
Advantages - Strong, easy to work with, versatile, potentially renewable, biodegradable
Disadvantages - Some timber is non-renewable; often treated with toxic chemicals.

Earth-wise tips - Use recycled wood or timber from sustainable sources, with no chemical treatments.