Tips on Fasteners for Pressure Treated Building Materials

Pressure treated wood is a popular choice for outdoor projects because it is resistant to decay and insect damage. However, it is important to recommend the correct hardware with pressure treated wood to ensure that your customer's project is durable and long-lasting. Lumber aisle associates should be prepared to make recommendations to DIYers and contractors based upon the specific project.   

Why is it important to recommend the correct hardware and fasteners.  

The chemicals used in pressure treated wood can be corrosive to some types of hardware. If you recommend the wrong hardware, it could rust prematurely and fail, which could lead to the failure of your customer's entire project. It is a good idea to take a look at the fastener containers to make sure your customers are buying fasteners that meet standards. The International Building Code and International Residential Code require metal fasteners that are in contact with any preservative treated wood be hot-dipped galvanized material meeting ASTM A 153 and connectors (ASTM A 653 Class G185 sheet) or better. Fasteners not meeting or exceeding these requirements could result in premature failures and degradation of fasteners and treated wood.   

What type of hardware and fasteners should your customer use? 

The best type of hardware to use with pressure treated wood is hot-dipped galvanized steel or stainless steel. These materials are highly resistant to corrosion and will last for many years. 

If your customer’s project is located in a coastal area or a region with high humidity, you may want to recommend using stainless steel hardware. Stainless steel is the most corrosion-resistant material available and is ideal for use in harsh environments. 

Other things to consider... 

When selecting hardware for your customer’s pressure treated wood project, it is also important to consider the size and length of the fasteners they will need. The size and length of the fasteners will depend on the type of project your customer is working on, and the thickness of the wood being used.  With dissolved copper azole preservative-treated wood, factory coated aluminum, or an insulating moisture-resistant barrier should be used between the treated wood and the aluminum. See the end tag for type of treatment (CA-C indicates dissolved copper azole).  

It is also important to note the difference between screws and nails. If choosing screws, remember that they take longer to drive than nails but hold boards more securely and will allow for easier removal if necessary.  

If choosing nails, use 3 1/2” long nails on nominal two-inch decking and 3” nails for 5/4” decking. Use two nails across a 2 x 4 and three across a 2 x 6. Drive nails at a slight angle toward each other. To reduce splitting when using nails, especially near the ends of boards, drill a pilot hole about three quarters the diameter of the nail. For dense or brittle wood, grind sharpness from nails or blunt the points by striking them carefully with a hammer.   

You should also consider your customer’s environmental conditions that your customer’s project will be exposed to. If your customer’s project is in a windy area, you may want to recommend longer screws or nails to provide a more secure hold. 

Concluding... 

By selecting the correct hardware for your customer’s pressure treated Wolmanized® CA-C (Copper Azole) building materials, your customer can ensure that the project is durable, long-lasting, and safe. 

Regarding outdoor projects, always consult manufacturer’s recommendations and consider the specific needs of your customer’s project including size length, and environmental conditions. By recommending the right hardware and fasteners, your customers can enjoy the beauty and functionality of pressure-treated building materials for years to come.