Bengkirai (Shorea laevis): Another Excellent Hardwood for Durable Wooden Houses
While Ulin (ironwood) rightfully earns its reputation as a champion of durability, Bengkirai (Shorea laevis), also known as Yellow Balau, emerges as another formidable hardwood, particularly well-regarded for its strength and resilience in wooden house construction, especially in tropical regions like Bali.1 Belonging to the Shorea genus, a group of commercially important timber trees in Southeast Asia, Bengkirai offers a compelling alternative with its own set of advantages.2
Strength and Density: A Solid Foundation (Approx. 2 Minutes)
Bengkirai boasts a high density, typically ranging from 880 to 990 kg/m³ at 12% moisture content, placing it firmly in the hardwood category. This density contributes significantly to its strength and resistance to physical stress.3
Technical Data Highlights:
- Density: 880-990 kg/m3 kg/m³ (at 12% moisture content)
- Janka Hardness: Around 1798 lbf (7990 N), indicating excellent resistance to indentation and wear, even surpassing some grades of oak.4
- Bending Strength (MOR): Approximately 20,950 psi (144 MPa), demonstrating its ability to withstand significant loads without breaking.5
- Stiffness (MOE): Around 2,900,000 psi (20,000 MPa), indicating its resistance to bending and deformation.
These technical figures highlight Bengkirai’s robust nature, making it a reliable choice for structural components like beams, columns, and rafters in a wooden house. Its strength ensures the overall stability and longevity of the structure, providing peace of mind for homeowners in Bali, where weather conditions can be demanding.
Natural Durability and Resistance
Bengkirai is classified as durable to very durable (Class 2-3 according to EN 350), meaning it offers good resistance to fungal attacks and moderate resistance to termites, particularly the heartwood. While not as inherently resistant as Ulin, its natural durability is still considerable and can be further enhanced with proper treatment.
Technical Data Highlights:
- Natural Durability: Class 2-3 (Durable to Very Durable)
- Termite Resistance: Generally considered durable, though the sapwood is less resistant.
- Resistance to Decay: Good natural resistance to fungal decay.
- Weather Resistance: Known for its good performance in outdoor applications.
This level of natural durability makes Bengkirai suitable for various parts of a wooden house, including decking, cladding, and even some structural elements. Its ability to withstand exposure to the elements makes it a popular choice for outdoor features in Balinese villas.
Advantages of Bengkirai for Wooden Houses
Choosing Bengkirai for a wooden house in Bali offers several advantages:
- Cost-Effectiveness: Generally, Bengkirai is more affordable than premium Ulin, making it a viable option for those seeking a durable hardwood within a more manageable budget.
- Workability: While still a hardwood, Bengkirai is generally easier to work with than Ulin, allowing for smoother cutting, planing, and fastening, potentially reducing construction time and labor costs.
- Aesthetic Appeal: Bengkirai boasts a warm, brownish-yellow to reddish-brown color with a generally straight or interlocked grain, offering a beautiful and natural look that complements Balinese architectural styles.6
- Availability: Bengkirai is more readily available in the Southeast Asian timber market compared to the increasingly scarce Ulin.
Conclusion:
Bengkirai (Shorea laevis) stands as an excellent alternative to Ulin for building durable wooden houses and villas in Bali. While Ulin boasts unparalleled density and natural resistance, Bengkirai offers a strong combination of durability, strength, workability, and a more accessible price point. Its proven performance in outdoor applications and its attractive aesthetic make it a highly suitable hardwood for crafting long-lasting and beautiful Balinese homes. By understanding its technical properties and advantages, builders and homeowners can make informed decisions to create sturdy and enduring wooden structures that harmonize with the island’s unique environment.
