NW 100^® Pressure Treated Wood Fastener and Hardware Information

• Use corrosion-resistant fasteners

Wood products pressure treated with NW 100 preservative are designed for long-term performance in outdoor applications and, therefore, requires nails, screws, fasteners, hardware and metal products that are high-quality and corrosion-resistant.

Fasteners (and other metal products) for use with wood products pressure treated with
NW 100 preservative include:

• Hot-Dip Galvanized* (The minimum standard)

Fastener, hardware and metal product manufacturers have suggested the minimum Hot-Dip Galvanized requirements for use with treated wood should conform to the following ASTM Standards: ASTM-A153 (for Hot-Dip fastener products) and ASTM-A 653 (Coating Designation G-185 for Hot-Dip connector and sheet products).

• Stainless Steel

Stainless steel fasteners and connectors are required for permanent wood foundations below grade and are recommended for use with treated wood in other severe exterior applications such as swimming pools, salt water exposure, etc. - Type 304 and 316 are the recommended grades to use.

• Other fasteners, hardware or any metal product as recommended by the manufacturer

There may be additional products (other than stainless steel or hot-dip galvanized) which are suitable for use with NW 100 pressure treated wood. Please consult with the individual fastener, hardware, or metal product manufacturer for recommendations for use of their products with NW 100 treated wood.

• Aluminum should not be used in direct contact with NW 100® treated wood

Spacer materials or other physical barriers are recommended to prevent direct contact of NW 100® treated wood and aluminum products. When using NW 100 pressure treated wood in close proximity to aluminum products, such as aluminum siding, flashing, furniture, and door and window frames, a 1/4” minimum spacing must be allowed for between the NW 100 pressure treated wood and the aluminum products. Another option is to use a polyethylene barrier, with a minimum thickness of 10 mils, between the NW 100 pressure treated wood and the aluminum product to prevent direct contact of the wood and the aluminum.  Certain adhesives add extra holding power. Apply adhesives in accordance with manufacturer’s directions.

* Electroplated galvanized fastener and metal products are typically not accepted by the building codes for use in exterior applications, regardless of the type of wood used.

For more information, download NW 100® Fastener and Hardware Information Sheet