Seasoning of Timber – Purpose, Advantages & Methods

Seasoning of timber is a crucial process that involves removing moisture from wood to bring it into balance with the surrounding atmospheric conditions. This ensures that the timber remains stable and durable when used in various applications. In simpler terms, it’s like preparing the wood to be strong, dry, and resistant to decay.

Purpose of Seasoning

Seasoning serves several important purposes:
1. Enhancing Properties : Seasoning makes timber harder, stiffer, and stronger. It also improves its electrical resistance, making it more versatile for different uses.

2. Ease of Workability : Properly seasoned timber is easier to work with during shaping and crafting, making it more convenient for builders and carpenters.

3. Maintaining Shape and Size : Seasoning helps preserve the original shape and size of timber components, preventing undesirable warping or cracking.

4. Preventing Decay : Seasoning safeguards timber from the harmful effects of fungi and insects, ensuring its longevity.

5. Enabling Joinery : Well-seasoned timber is suitable for effective gluing, allowing pieces to be securely joined together.

6. Preparing for Finishing : Seasoned timber is ready to receive treatments like paints, varnishes, and preservatives, enhancing its appearance and protection.

7. Fuel Readiness : Seasoned timber burns efficiently when used as fuel, providing a valuable energy source.

Methods of Seasoning

There are two main methods of seasoning timber: Natural Seasoning and Artificial Seasoning.

Natural Seasoning
Natural seasoning relies on environmental conditions to slowly remove moisture from the timber. It includes two methods:

• Air Seasoning : This method involves allowing moisture to evaporate naturally from the wood. It’s considered the best approach for even and consistent drying.
• Water Seasoning : Logs are submerged in water, allowing sap to be washed out. Afterward, they are left to air dry. This method is particularly effective for certain types of timber.

Advantages of Natural Seasoning
Natural seasoning offers several advantages:

• It can achieve the desired moisture content (10-20%) based on climate.
• It doesn’t require specialized supervision.
• It’s a cost-effective method, especially for thicker sections of timber.

Artificial Seasoning
Artificial seasoning involves controlled environments to expedite the drying process. There are various methods:

• MC Neills Seasoning : This method is considered highly effective. It uses a controlled chamber with a large water surface to create a moist atmosphere, resulting in hardened and denser timber.
• Kiln Seasoning : This method uses an airtight chamber where heated, moist air is circulated to dry the timber quickly. It renders the timber brittle and can bleach deep-colored wood.
• Seasoning by Boiling in Water : Timber is immersed in boiling water for four hours. This method reduces strength and elasticity but minimizes shrinkage.
• Seasoning by Steaming : Similar to boiling, but the timber dries quickly after steaming. It prevents dry rot but is more expensive.
• Chemical Seasoning : Timber is immersed in a solution of suitable salts, leading to controlled drying. This decreases the chance of external cracks.
• Electrical Seasoning : High-frequency AC currents are used to dry the timber rapidly. This is a swift method, though it comes with higher initial costs.

Precautions During Seasoning of Timber

It’s important to take certain precautions during the timber seasoning process:

• Maintain consistent environmental conditions for moisture removal.
• Ensure uniform drying for all logs to prevent shape irregularities.
• Protect air-seasoned timber from high humidity and rain exposure.
• Maintain suitable gaps between logs for proper air and water circulation.