Preserving Timber (Junior Cert Wood Technology): Revision Notes

Wood Preservatives

Definitions

• Preservative: A substance used to keep wood safe from decay, insects, and other damage.
• Oil-based preservative: A preservative that uses oil to soak into and protect wood.
• Water-based preservative: A preservative with water as the primary solvent.
• Organic solvent-based preservative: A wood preservative using organic solvents to thin chemicals for protection.

Oil-based Preservatives

• Content:
  • Penetration Method: Uses oil to seep into wood fibres, offering protection from within. Ideal for deep penetration but requires time between coats.
  • Effectiveness: Protects against fungi, insects, and weathering, though less effective on the surface compared to varnish-like finishes.
  • Use Cases: Suitable for marine wood and utility poles due to deep penetration.
  • chatImportant

    Environmental Concerns: Risk of oil spills and toxic runoff, especially in rainy conditions. Limited use in sensitive areas.

Water-based Preservatives

• Content:
  • Composition: Usually includes copper or biocides, enhancing protection by forming a barrier, while being more eco-friendly.
  • Safety Features: Less toxic than oil-based, making them safer for residential use.
  • Application: Applied with standard tools; complete coverage is necessary to avoid missed spots.
  • Use Cases: Ideal for household items like furniture. Safer and suitable for areas near people.
  • Drawbacks: Can leach, especially in wet areas, necessitating frequent reapplication.
• Diagrams:
  • 

Organic Solvent-based Preservatives

• Content:
  • Chemical Properties: Uses chemicals that bond with wood, effective in preventing damage from biological and environmental threats.
  • Durability: Provides long-lasting protection in harsh environments like industrial areas but poses environmental threats, including high emissions.
  • chatImportant

    Limitations: Highly volatile, contributing to pollution, and can pose health risks if not used properly.

  • Environmental Impact: Major due to solvent emissions; requires strict measures to reduce effects.
• Diagrams:
  • 

Comparative Analysis

• Content:
  • A table comparing the advantages and disadvantages of oil-based, water-based, and organic solvent-based preservatives concerning application ease, protection level, and environmental impact.
• Diagrams:
  • 

---

Summary