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Lag Screws (Lag Bolts) | Hex Head | Steel & Stainless Steel

What is a lag screw?

Lag screws, or lag bolts, are heavy duty screws usually used to fasten heavy lumber together or connect lumber to masonry. For example commonly used in deck and dock building. To prevent splitting it is suggested a pilot hole to be drilled first. They are generally much larger in size than standard wood screws with common sizes from 1/4" to 3/4" diameter and up to 36” long.

They are available in plain steel (for dry environments) and Zinc plated for silver look and resist corrosion in moist environments. Hot dipped galvanized is a thick coating for better corrosion resistance and are a good option for ACQ treated deck lumber. Stainless Steel is the ultimate corrosion resistance for heavy wet (ocean) environments.

Lag screws are also available in Metric DIN 571 sizes.

We also offer Lag screws with a washer head. These are specifically designed for attaching track and flag brackets of garage door assemblies to wooden door jambs.