Galvanized Lag Screws Treated Lumber

When a screw is galvanized it s submerged inside a container filled with molten zinc.

Galvanized lag screws treated lumber.

The national design specification for wood construction nds refers to these fasteners as lag screws. Common metal parts used with pressure treated wood are connector plates joist hangars bracing plates and fasteners of all types. Known as hot tip galvanizing this finishing process adds a layer of zinc over the surface of a screw. Steel self tapping timber screws 50 box model 16648 95 53 box.

The g 185 coating is equivalent to 1 85 ounces of zinc per square foot of steel. It gets eaten away by the copper in treated wood. Owt ornamental wood ties 1 4 in. The way that corrosion resistance is measured on galvanized products is to weigh them before and after submergence in a corrosive medium to find out how much of the zinc has oxidized.

On galvanized steel fasteners and hardware zinc is like the candy coating. Copper based formulations may be used in interior or exterior applications and include the traditional chromated copper arsenate cca and advanced products such as alkaline copper quat acq or copper azole ca b. The idea that double or even triple dipped galvanized fasteners are required for corrosive environments is a frequent misconception. Galvanized steel screws nails and bolts used with copper treated wood must be hot dipped in molten zinc at 850 degrees fahrenheit.

Hex galvanized lag screw 25 pack 31 model 804680 63 67 box. Nevertheless you should not use them with pt lumber in contact with the soil in high moisture areas or in areas with salt content in the air. Galvanized screws are characterized by the presence of a protective zinc shell that s achieved by submerging the screws in molten zinc. Hex galvanized lag screw 25 pack 105 model 803720 13 95.

These dull gray fasteners must meet the astm a153 standard for zinc coating quality and the g 185 standard for coating amount. Galvanized screws included as fasteners in either wood or metal projects will almost certainly last longer. Lag bolts are used when loads are of relatively large magnitude need to be transmitted through a joint and when an excessively long bolt would be required to make a connection or when one side of a through bolted connection may be inaccessible. Fasteners with external threads cannot be double or triple dipped galvanized.

This means any material galvanized to either a153 or f2329 will be more than adequate for use with pressure treated timbers. Mechanically galvanized screws are generally suitable for decks and other outdoor projects made of pressure treated lumber. Hot dip galvanized steel can withstand the harsh chemicals and slow the corrosion rate.