---
title: "Painting on new and old woodwork"
subject: "Building Technology"
chapter: 9
key: "semester_6/building_technology:painting-new-old-wood"
source: https://www.bctengineer.com/q/semester_6/building_technology/painting-new-old-wood
site: BCT Engineering
---

# Painting on new and old woodwork

Building Technology · Chapter 9: Finishing works

- Asked in: 2070 Magh; 2062 Poush (old course) (asked 2 times)
- Video: [Repainting old woodwork Like A PRO | Prepare Woodwork For Painting + SKIRTING BOARDS & ARCHITRAVES](https://www.youtube.com/watch?v=a8h1cZXSBQA) — DIY For Beginners
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_6/building_technology/painting-new-old-wood
- Whole chapter: https://www.bctengineer.com/md/semester_6/building_technology/chapter-9

## Question

Define painting. Describe the procedure of painting in new and old woodworks (and cement surfaces).

## Short answer

Painting is a liquid coating for protection and decoration. New wood requires sanding, knotting, priming, stopping, undercoat and finishing coat. Old wood needs old paint removal, sanding, patch priming, and finishing; cement surfaces need curing, alkali-resistant primer, putty and two coats.

## Answer

**Painting** is the application of a liquid coating to a surface to protect it from weather, dampness, rot and corrosion, and to give it a good appearance and colour.

#### New woodwork
1. **Preparation:** the surface is rubbed smooth with sandpaper, and knots are covered with knotting (shellac) to stop resin bleeding.
2. **Priming:** a coat of wood primer (red lead and linseed oil) is applied and allowed to dry for 24 hours.
3. **Stopping:** nail holes and cracks are filled with putty (whiting and linseed oil), and the surface is rubbed down.
4. **Undercoat:** one or two coats of paint of a lighter shade are applied 24 hours apart, each sandpapered when dry.
5. **Finishing coat:** one or two coats of the final colour (oil paint or enamel) are applied.

#### Old woodwork
1. **Cleaning:** loose old paint is removed by scraping, wire brushing or a paint remover, and the surface is washed with mild soap water or sugar soap and then dried.
2. **Rubbing down** with sandpaper.
3. **Patch priming** of bare areas, stopping and filling of holes, then sandpapering.
4. **Undercoat and finishing coats** as for new woodwork. If the old paint is sound, only one or two finishing coats are applied.

#### Cement surfaces
The plaster must dry for 3-4 weeks. An alkali-resistant primer is applied, then putty, then two coats of emulsion or cement paint.

## Check yourself

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

1. What is painting?
   A. Plastering
   B. Applying a liquid coating to protect a surface and give colour
   C. Filling joints
   D. Fixing tiles
   Answer: B. Paint protects from weather, damp, rot and corrosion and decorates. (Key point: Painting definition)

2. Why are knots in new wood covered with knotting solution (shellac)?
   A. To give colour
   B. To speed drying
   C. To stop resin bleeding
   D. To fill holes
   Answer: C. Resin from knots would otherwise spoil paint. (Key point: Knotting)

3. What is stopping?
   A. Final coat
   B. Priming
   C. Removing old paint
   D. Filling nail holes and cracks with putty and rubbing down
   Answer: D. Putty of whiting and linseed oil fills defects. (Key point: Stopping)

4. What is the first step in repainting old woodwork?
   A. Remove loose old paint, wash and dry
   B. Apply putty
   C. Finish coat
   D. Add undercoat
   Answer: A. Old loose paint must be removed by scraping or remover before rubbing down. (Key point: Old wood)

## Related in Building Technology

- [Emulsion paint; painting on new woodwork](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Apainting-wood-emulsion) — Building Technology, chapter 9
- [Paints, oil paint ingredients, painting woodwork](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Apaints-characteristics-066bh) — Building Technology, chapter 9
- [Paints, varnishes, painting procedures](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Apaints-varnish-064j) — Building Technology, chapter 9
- [Painting work on metal surfaces](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Apainting-metal) — Building Technology, chapter 9, asked 2×
- [Painting on masonry; causes and remedies of cracks](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Apainting-masonry-cracks) — Building Technology, chapter 9

## Related in other subjects

- [ESL of new machine; when to replace old](https://www.bctengineer.com/question.md?key=semester_6%2Fengineering_economics%3Aeconomic-service-life-new-machine-old) — Engineering Economics, chapter 5
- [Filter definition and denormalization from ωold to ωnew](https://www.bctengineer.com/question.md?key=semester_5%2Ffilter_design%3Afilter-normalization-frequency-change) — Filter Design, chapter 1
- [Painting a new plastered surface](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Apaint-new-plastered-surface) — Civil Engineering Materials, chapter 9
- [Painting a new wood surface](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Apaint-new-wood-surface) — Civil Engineering Materials, chapter 9