---
title: "Functions of mortar"
subject: "Civil Engineering Materials"
chapter: 6
key: "semester_3/civil_engineering_materials:functions-of-mortar"
source: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/functions-of-mortar
site: BCT Engineering
---

# Functions of mortar

Civil Engineering Materials · Chapter 6: Mortar

- Asked in: 2080 Bhadra, 2 marks; 2080 Baisakh, 2 marks; 2078 Bhadra, 2 marks; 2075 Asoj, 2 marks; 2068 Chaitra, 2 marks; 2076 Chaitra, 1 marks; 2073 Shrawan, 1 marks; 2074 Asoj, 1 marks (asked 8 times)
- Video: [Mortar | uses of mortar | Composition of mortar | construction material | brick mesonary | Mohan](https://www.youtube.com/watch?v=J_7EbjnR_CY) — Digitech education
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/functions-of-mortar
- Whole chapter: https://www.bctengineer.com/md/semester_3/civil_engineering_materials/chapter-6

## Question

Write down the functions of mortar in civil construction.

## Short answer

Mortar binds masonry units, distributes loads evenly, provides a level bed, and fills joints to resist weather penetration. It also holds embedded fixtures, serves for plastering, and improves structural durability.

## Answer

**Mortar** is a paste of a binding material (cement, lime or mud), fine aggregate (sand) and water, used to join building units. Its functions are:

1. **Binds** bricks, stones or blocks into a solid mass.
2. **Distributes load** evenly over the bedding surface of the masonry units, avoiding point loads.
3. **Bedding:** gives an even, level bed so the units sit properly and the courses stay horizontal.
4. **Fills joints**, gaps and voids between units, making the wall weather-tight and preventing the entry of rain, wind, dust and insects.
5. **Holds fixtures** such as door and window frames, hold-fasts and steel bars embedded in masonry.
6. **Plastering and pointing:** used for finishing walls and floors and for giving a decorative surface.
7. **Resists weathering** and increases the durability of the structure.
8. **Absorbs small movements and shrinkage** (flexible lime or mud mortar), and is used for flooring, damp-proofing and as a base for tiles.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. One function of mortar is to:
   A. Distribute load evenly over the bedding of masonry units
   B. Reinforce steel
   C. Replace bricks
   D. Cool the wall
   Answer: A. Avoids point loads. (Key point: Load distribution)

2. Mortar fills joints to:
   A. Make wall weak
   B. Make the wall weather-tight
   C. Increase colour
   D. Reduce bond
   Answer: B. Prevents entry of rain, wind, dust, insects. (Key point: Joints)

3. Mortar bedding provides:
   A. A rough bed
   B. Waterproof layer only
   C. An even level bed so courses stay horizontal
   D. Reinforcement
   Answer: C. Units sit properly. (Key point: Bedding)

## Related in Civil Engineering Materials

- [Stepwise preparation of cement mortar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Astepwise-preparing-cement-mortar) — Civil Engineering Materials, chapter 6, asked 4×
- [Properties of mortar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aproperties-of-mortar) — Civil Engineering Materials, chapter 6, asked 3×
- [Precautions while applying cement mortar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aprecautions-applying-cement-mortar) — Civil Engineering Materials, chapter 6, asked 3×
- [Classification of mortar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aclassification-types-mortar) — Civil Engineering Materials, chapter 6, asked 2×
- [Steps of applying cement mortar](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Asteps-applying-cement-mortar) — Civil Engineering Materials, chapter 6
- [Define mortar in brief](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Adefine-mortar) — Civil Engineering Materials, chapter 6, asked 4×

## Related in other subjects

- [Functions and properties of mortar](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Amortar-functions-properties) — Building Technology, chapter 3
- [Equipment for concrete construction and functions](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Aconcrete-equipment-functions) — Construction Management, chapter 4
- [Detailed specification of cement sand mortar 1:4](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Adetailed-spec-cs-mortar-1-4) — Construction Management, chapter 12, asked 2×
- [Detailed specification of cement sand mortar 1:6](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Adetailed-spec-cs-mortar-1-6) — Construction Management, chapter 12, asked 2×