---
title: "Paint, varnish and their purpose"
subject: "Civil Engineering Materials"
chapter: 9
key: "semester_3/civil_engineering_materials:paint-varnish-purpose"
source: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/paint-varnish-purpose
site: BCT Engineering
---

# Paint, varnish and their purpose

Civil Engineering Materials · Chapter 9: Paint and Varnishes

- Asked in: 2072 Chaitra, 4 marks
- Video: [Paints and Varnishes | Paints Composition | Characteristics Of Good Paint |](https://www.youtube.com/watch?v=JmKSNpkuz1A) — Engr. DANISHWAR KHAN
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/paint-varnish-purpose
- Whole chapter: https://www.bctengineer.com/md/semester_3/civil_engineering_materials/chapter-9

## Question

What do you mean by paint and varnishes? What is the purpose of using it?

## Short answer

Paint is a liquid mixture that forms an opaque coloured protective film. Varnish is a resin solution that dries to a transparent glossy film. They protect surfaces from moisture, decay and corrosion, decorate, and make surfaces hygienic and easy to clean.

## Answer

**Paint** is a liquid mixture of a base, pigment, vehicle, drier and thinner that forms a hard, opaque coloured film when it dries on a surface. **Varnish** is a solution of resin (natural or synthetic) in oil, turpentine or spirit that dries to a hard, glossy, transparent film.

#### Purpose of paints

- Protect surfaces (wood, steel, plaster) from weather, moisture, decay and corrosion.
- Decorate with colour and a smooth finish, and hide defects.
- Make surfaces hygienic and easy to clean.
- Increase the life of the structure and reduce maintenance.

#### Purpose of varnishes

- Protect the surface (mostly wood) from moisture, dust and insects, while keeping the natural grain and colour visible.
- Give a glossy, attractive finish to furniture, doors, windows and floors.
- Provide a hard, water-resistant layer over painted surfaces and paintings.
- Make the surface easy to clean.

## Check yourself

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

1. Which best defines paint?
   A. Resin dissolved in spirit giving a transparent film
   B. Chalk mixed with water only
   C. A liquid mixture of base, pigment, vehicle, drier and thinner forming an opaque coloured film
   D. A bitumen solution used for waterproofing
   Answer: C. Paint is a mixture of base, pigment, vehicle, drier and thinner that dries to a hard opaque coloured film. (Key point: Definition of paint)

2. What distinguishes varnish from paint?
   A. It contains pigment and is opaque
   B. It is a resin solution that dries to a transparent glossy film
   C. It is always water-based
   D. It has no protective use
   Answer: B. Varnish is resin in oil, turpentine or spirit and dries to a hard, glossy, transparent film. (Key point: Definition of varnish)

3. Why is varnish preferred to paint on good wooden furniture?
   A. It hides defects completely
   B. It is cheaper than any paint
   C. It protects while keeping the natural grain and colour visible
   D. It makes the wood rust-proof
   Answer: C. Being transparent, varnish protects wood while showing the grain and colour. (Key point: Purpose of varnish on wood)

4. Which is a purpose of paint but not of clear varnish?
   A. Protecting from moisture
   B. Making surfaces easy to clean
   C. Hiding defects with colour
   D. Giving a hard layer
   Answer: C. Paint is opaque coloured so it decorates and hides defects; clear varnish cannot. (Key point: Purpose of paint)

## Related in Civil Engineering Materials

- [Paint versus varnish](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Apaint-vs-varnish) — Civil Engineering Materials, chapter 9, asked 5×

## Related in other subjects

- [Paints, varnishes, painting procedures](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Apaints-varnish-064j) — Building Technology, chapter 9