There are several types of mortar used in construction based on binding material, application, density, and purposes. Mortar is a workable paste prepared by adding water to a mixture of binding material and fine aggregate. The plastic paste is then used to hold building material together including bricks and stones. Below are the different types of mortar used in construction;
1. Bricklaying or Stone Laying Mortar
Bricklaying or stone laying mortar is used to bind bricks and stones in masonry construction. The proportions of ingredients for bricklaying or stone laying mortar is decided based on the kind of binding material used.
2. Finishing Mortar
Finishing mortar is used for pointing and plastering works. It is also used for architectural effects of building to give aesthetic appearances. The mortar used for ornamental finishing should have great strength, mobility, and resistance against atmospheric action like rain, wind, etc.
3. Cement Mortar
Cement is used as a binding material in this type of mortar and sand is employed as aggregate. The proportion of cement and sand is decided based on the specified durability and working conditions.
Cement mortar will give high strength and resistance against water. The proportion of cement to sand may vary from 1:2 to 1:6.
4. Lime Mortar
In this case, lime is used as binding material. There are two types of limes namely fat lime and hydraulic lime. Fat lime in lime mortar requires 2 to 3 times of sand and it is used for dry work.
Hydraulic lime and sand in 1:2 ratios will give good results in damp conditions and also suitable for waterlogged areas.
Finally, the lime mortar has high plasticity so it can be placed easily.
5. Gypsum Mortar
Gypsum mortar consists of plaster and soft sand as binding material and fine aggregate. Commonly, it has low durability in damp conditions.
6. Gauged Mortar
In gauge mortar combination of lime and cement is employed as a binder material, and sand used as fine aggregate. Gauge mortar is, essentially, lime mortar whose strength increased by adding cement.
Consequently, the mortar will have high plasticity of the lime and high strength of the cement. The ratio of cement to lime ranges from 1:6 to 1:9, and it is cost-effective.
7. Surkhi Mortar
In surkhi mortar, lime is used as binder material and surkhi is employed as fine aggregate. The surkhi is finely-powdered burnt clay that provides more strength than sand and cheaply available in the market.
8. Aerated Cement Mortar
Basically, it is cement mortar to which an air-entraining agent is added to increase plasticity and workability. The resulted mortar is termed aerated cement mortar.
9. Mud mortar
In this type of mortar, mud is used as binding material and sawdust, rice husk, or cow-dung is used as fine aggregate. Mud mortar is useful where lime or cement is not available.
The use of mud mortars in the Middle-East and Central Asia and American cultures of the south-western USA is well documented.
10. Heavy Mortar
If the mortar has a bulk density of 15 KN/m3 or more then it is called as heavy mortar. Generally, heavy quartzes are used as fine aggregate in this type of mortar.
11. Lightweight Mortar
If the mortar has a bulk density of less than 15 KN/m3 then it is called light mortar. Lightweight mortar is prepared by mixing lime or cement as binder, sand, and sawdust, rice husk, jute fibers, colors, or asbestos fibers. Cinder mortar is a variety of light-weight mortars. Lightweight mortar is generally used in soundproof and heatproof constructions.
12. Fire Resistant Mortar
Fire-resistant mortar is prepared by mixing aluminous cement with the fine powder of fire bricks. If there are any fire warnings to the structures in a particular zone, then fire-resistant mortar will be used which acts as a fireproof shield.