DIN 571 Wood Screw vs Lag Bolt / Lag Screw: What’s the Difference?

When sourcing heavy-duty fasteners for wood applications, DIN 571 wood screws and Lag Bolts (Lag Screws) are often discussed together. Their similar appearance—hex head, coarse thread, and large diameter—frequently leads to confusion.

However, understanding the real difference between DIN 571 vs lag bolt is essential for correct specification, installation, and project compliance. As a reliable fastener manufacturer, Xinchi is glad to introduce the differences to you.

DIN 571 Wood Screw vs Lag Bolt: Standard System Differences

Although DIN 571 wood screws and lag bolts may look the same, they come from different standard systems. DIN 571 is a clearly defined German industrial standard, widely used in Europe and in projects that follow DIN or EN specifications. It regulates dimensions, head type, thread design, and tolerances, ensuring consistency in engineering applications.

Lag Bolt, more accurately called Lag Screw, is a commonly used American term rather than a single strict standard. It is widely referenced in North American construction and engineering documents, usually following ANSI or ASME-related practices. This difference in standard background explains why DIN 571 vs lag bolt comparisons are especially important in international sourcing and cross-border projects.

Wood Screw Comparison in Engineering Specifications

From an engineering perspective, both DIN 571 wood screws and lag bolts are designed for high-load wood connections, such as timber structures, beams, brackets, and metal-to-wood assemblies. However, how they are specified in drawings and bills of materials differs significantly.

DIN 571 wood screws are typically specified by name in European technical documents, while lag bolts are more commonly described by size and length in US-based projects. This wood screw comparison shows that selection is often driven by engineering norms and inspection requirements, not by appearance alone. Using the correct terminology ensures smoother communication between designers, suppliers, and contractors.

DIN 571 Wood Screw vs Lag Bolt: Installation Method and Tool Choice

Installation is another practical area where DIN 571 wood screws and lag bolts are compared. Most DIN 571 wood screws use an external hex head, allowing installation with a wrench or socket to achieve high tightening torque. This makes them suitable for structural fastening where strength and stability are critical.

Lag bolts also commonly use an external hex head, which is why they often look identical to DIN 571 wood screws. In some customized applications, lag screws may use internal hex (hex socket) drives, particularly where space limitations or appearance considerations apply. Regardless of the drive type, both fasteners usually require pre-drilled holes, especially when used in hardwood or dense materials.

DIN 571 vs Lag Bolt: Which Is Right for Your Project?

Choosing between DIN 571 wood screws and lag bolts depends on your project’s standard system rather than the fastener’s appearance. Projects based on DIN or EN standards typically require DIN 571 wood screws for compliance, while North American projects more commonly specify lag bolts.

In international trade, clearly confirming whether DIN 571 is acceptable as an equivalent to a lag bolt helps avoid specification mismatches and costly rework. Matching the fastener standard to the project documentation is always more important than relying on visual similarity.

Reliable Supply of DIN 571 Wood Screws and Lag Bolts from Xinchi Fasteners

Xinchi Fasteners has been focused on fastener manufacturing and supply since 2007, offering stable and reliable solutions for global customers. The factory operates 102 cold heading machines, with a daily production capacity exceeding 10 million pieces, supporting large-volume orders of DIN 571 wood screws, lag bolts, and other industrial fasteners.

The newly completed manufacturing base covers an area of 30,000 square meters, consisting of two six-story production buildings, providing strong capacity for standardized production, quality control, and timely delivery.

As a trusted fastener supplier, we offer a wide range of high-quality fasteners, including nuts, screws, bolts, rivets, and washers. With long-term experience in international fastener supply, Xinchi Fasteners supports customers in meeting DIN, EN, and market-specific requirements with consistent quality and professional service.