Mortar is defined as a paste (capable of setting and hardening) made by combining fine aggregates such as sand with binding material (clay, gypsum, lime or cement). Building mortars are mixtures used to bond bricks, stones, blocks, and other materials. In the construction industry, various types of mortar are used. Cement mortar is the most commonly used mortar type. Aside from that, other types of mortars are used on occasion.
Types of Mortar
Below is the list of different mortar types along with the mix proportions and preparation method.
- Cement Mortar
- Lime Mortar
- Lime-Cement Mortar
- Surkhi Mortar
- Mud Mortar
- Special Mortars
Also Read : Building Construction : Procedure For Constructing a Building
Also Read : Different Grades of Cement
Cement Mortar
In order to make cement mortar, you must mix cement, sand, and water in the appropriate proportions.
For walls made of bricks, stones and huge blocks, Portland cement and blast furnace slag cement make excellent mortars.
Plastering, rendering smooth finishes, and damp proof courses are all done with cement mortars.
Cement Mortar Mix Proportions
| Sr.No | Type of Work | Cement | Sand |
| 1 | Foundation | 1 | 3-4 |
| 2 | Masonry | 1 | 4-5 |
| 3 | Reinforced Brickwork | 1 | 3 |
| 4 | Plastering a) Interior b) Exterior | 1 1 | 4 5-6 |
| 5 | Pointing | 1 | 1-3 |
How to Prepare Cement Mortar?
- Manual mixing is material is done for small amounts of mortar, while mechanical mixers can be used for larger amounts.
- Sand is sieved, cleaned with water to remove dirt and dust, and dried for manual mixing.
- On a pucca platform, the dry sand is laid out uniformly, and then the cement is spread evenly over it.
- With spades, the materials are thoroughly mixed to achieve uniformity.
- After that, a depression is created in the middle of the mixture, and the needed amount of water is added.
- The dry mix is moved from the sides and placed on the edges of the depression formed until the water is completely absorbed by the mix.
- A spade is then used to smooth out the wet mix and create a uniform consistency in the mortar.
- For mechanical mixing, the cement, sand, and water are weighed out and placed into the cylindrical container of the mixer before it is turned on.
- Inside the container, a rotor with blades rotates and completely mixes the components.
Lime Mortar
Lime mortar is composed of lime, sand and water. Fat lime (quick or hydrated lime) or hydraulic lime can be used in mortar. Fat lime contains a high amount of calcium oxide.
Water loss and carbon dioxide absorption are the important factors in its hardening. Hydraulic lime contains trace amounts of silica, alumina, and iron oxide.
Putty or lime mortar is formed when it is mixed with water and it also has the ability to set and harden under water.
Lime Mortar Mix Proportions
| Sr.No | Type of Work | Type of Lime | Lime | Sand | F.M (sand) |
| 1 | Masonry | Hydraulic Lime | 2- 3 | 1.5- 2.5 | 1.5- 2.5 |
| 2 | Plastering | Fat Lime | 1- 2 | 2- 3 | 2- 3 |
| 3 | Pointing | Fat Lime | 1.5 | 2- 3 | 2- 3 |
How to Prepare Lime Mortar?
- The needed volumes of lime and sand are deposited on an impermeable floor or in a mixing tank.
- Dry ingredients are mixed well by turning them up and down with spades.
- Water is added, and the mortar is mixed again with spades until it reaches a uniform colour and consistency.
Lime-Cement Mortar
Cement and lime are mixed to make guarded mortar, also known as gauged mortar. Increased water retentivity, workability, bonding qualities, and frost resistance are all advantages of lime-cement mortar. The mortar is used in construction to get a good and smooth plaster finish.
Lime-Cement Mortar Mix Proportions
| Sr.No | Location | Cement | Lime | Sand |
| 1 | Inside Wall | 1 | 2 | 9 |
| 1 | 3 | 12 | ||
| 2 | Outside Wall | 1 | 1 | 6 |
| 1 | 2 | 9 |
How to Prepare Lime-Cement Mortar?
- Cement and sand are combined dry first for low lime content.
- Lime putty is mixed with the dry mix once it has been dissolved in water.
- The mixture is then thoroughly stirred with spades until a consistent consistency is achieved.
- Lime cement mortar with a high lime content is created in mills.
- lime and sand are first mixed separately in the form of a paste for the full day’s requirement.
- Then, in batches, cement is combined with lime mortar and consumed within an hour.
Surkhi Mortar
It’s made in the same way as lime mortar, but instead of sand, surkhi is used. When grinding surkhi, it should pass through a 4.75 mm sieve with less than 15% of the material passing through a 150 micron sieve. Occasionally, sand is also mixed in with the other ingredients.
Surkhi Mortar Mix Proportion
| Sr.No | Type of Mortar | Type of Work | Lime | Surkhi | Sand |
| 1 | Surkhi | Masonry & Foundation | 1 | 2 | – |
| 2 | Lime- Surkhi | Masonry & Foundation | 1 | 1 | 1 |
Mud Mortar
They are the most affordable sort of mortar, made using locally accessible ingredients and used for masonry work, floor surfacing, and wall plastering in low-cost homes. The plastered surfaces are sometimes coated with bituminous material to strengthen their resistance to rain water.
How to Prepare Mud Mortar?
- Generally, 150-250mm of earth is excavated to prepare the mud mortar.
- The clay nodules are then wetted and allowed to mature for a few days before being used.
- The use of fibrous material, such as cow dung, reduces shrinkage fractures.
- The ingredients are then properly combined and kneaded.
Special Mortars
Aside from the common mortars, there are certain unique mortars that are utilised in specific situations. Some of them are listed below.
- Damp-proofing mortar
- Sound absorbing mortar
- Joint Filling Mortar
Damp-proofing Mortar :
Damp proofing mortar is made with high grade sulphate-resisting portland cement or sulphate-resisting puzzolana cement as the binding material and quartz sand or crushed solid rock sand as the sand. Damp-proofing mortars prepared with expanding cement are used to create water-tight seams and joints.
Sound Absorbing Mortar :
Binding materials such as portland cement, slag cement, lime or gypsum are used to make these mortars. They are used as sound-absorbing plaster in order to reduce noise levels.
Joint Filling Mortar :
Joint filling mortars are used for filling joints between prefabricated reinforced concrete members. Portland cement and quartz sand is used in the production of this mortar.