---
title: "Defects caused by seasoning"
subject: "Civil Engineering Materials"
chapter: 7
key: "semester_3/civil_engineering_materials:seasoning-defects-timber"
source: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/seasoning-defects-timber
site: BCT Engineering
---

# Defects caused by seasoning

Civil Engineering Materials · Chapter 7: Timber

- Asked in: 2078 Bhadra, 2 marks
- Video: [Wood drying (2) Distortion](https://www.youtube.com/watch?v=ptGDxhYkmZY) — Aalto University - Wood Science
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/civil_engineering_materials/seasoning-defects-timber
- Whole chapter: https://www.bctengineer.com/md/semester_3/civil_engineering_materials/chapter-7

## Question

Explain any four defects in timber caused due to seasoning.

## Short answer

Seasoning defects include warping (bow, cup, twist, spring), surface checks, splits through the thickness, and internal honeycombing cracks. These result from uneven, rapid drying and internal stresses.

## Answer

Uneven or too-fast drying of timber causes the following defects.

1. **Warping:** a change of shape due to uneven shrinkage. It may be a bow (along the length), cup (across the width), twist (spiral) or spring (edgewise).
2. **Checks:** cracks on the surface running across the annual rings, caused by rapid drying of the outer part.
3. **Splits:** checks that pass through the thickness from one face to the other, mainly at the ends, due to quick drying.
4. **Honeycombing:** internal cracks and cavities, caused when the interior dries after the outer layer has already hardened (stresses from case hardening).
5. **Case hardening:** the surface dries and sets while the core is still wet, so the surface is first under tension; stresses reverse as the core dries, causing cracks later.
6. **Collapse:** flattening of cells due to fast drying of wet wood at high temperature.

## Check yourself

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

1. Warping includes
   A. Heart and star shakes
   B. Knots and burls
   C. Bow, cup, twist and spring
   D. Wane and chip marks
   Answer: C. Warping is change of shape from uneven shrinkage. (Key point: Warping)

2. A split differs from a check in that it
   A. Is internal
   B. Occurs only at knots
   C. Is caused by fungi
   D. Passes through the thickness from face to face
   Answer: D. Splits go right through. (Key point: Checks vs splits)

3. In case hardening
   A. The surface dries and sets while the core is wet, putting the surface in tension
   B. The core dries first
   C. The whole piece hardens evenly
   D. Fungi harden the surface
   Answer: A. Surface sets first. (Key point: Case hardening)

4. Honeycombing refers to
   A. Surface stains
   B. Internal cracks and cavities
   C. Bark pockets
   D. Spiral grain
   Answer: B. Honeycombing is internal. (Key point: Honeycombing)

## Related in Civil Engineering Materials

- [Defects of timber by natural forces](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Atimber-defects-natural-forces) — Civil Engineering Materials, chapter 7
- [Seasoning of timber and its necessity](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aseasoning-meaning-necessity) — Civil Engineering Materials, chapter 7, asked 8×
- [Methods of seasoning timber](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Amethods-of-seasoning-timber) — Civil Engineering Materials, chapter 7, asked 2×
- [Why timber is used; seasoning method](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Aseasoning-method-and-timber-use) — Civil Engineering Materials, chapter 7
- [Defects of timber](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Adefects-of-timber) — Civil Engineering Materials, chapter 7, asked 4×
- [Natural versus artificial seasoning](https://www.bctengineer.com/question.md?key=semester_3%2Fcivil_engineering_materials%3Anatural-artificial-seasoning) — Civil Engineering Materials, chapter 7

## Related in other subjects

- [Damp proofing and defects due to moisture](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Adamp-proofing-defects) — Building Technology, chapter 1
- [Types of timber and its defects](https://www.bctengineer.com/question.md?key=semester_6%2Fdesign_of_steel_and_timber_structure%3Atimber-types-defects) — Design of Steel and Timber Structure, chapter 9
- [Audible sound, reflected-sound defects, insulation](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Asound-audible-insulation) — Building Technology, chapter 1
- [Common acoustic defects](https://www.bctengineer.com/question.md?key=semester_6%2Fbuilding_technology%3Aacoustic-defects) — Building Technology, chapter 1