What's the Best Metal to Use for Deck Flashing?
If you are planning on installing deck flashing, you will probably be considering the various types of metal that can be used for the flashing. There are several metals that work well for deck flashing, and the type that you will need to use with your deck will depend on several different variables.
Understanding Metals Used in Wood Decking
These days, more and more treated wood makers are using metal fragments in the construction of wood used for decks. This is done in order to help the wood better resist decay and rot. More often than not, manufacturers of treated deck lumber will use special heavy metal alloys that have been heated and converted into a liquid form and then used in treating the wood. This results in a stronger piece of deck wood that is also less susceptible to termite or insect damage and more resistant to many types of diseases and other contaminants that attack wood.
Perhaps, the most common type of metal used in the making of deck lumber is copper. In fact most of the popular chemical wood treatment liquids not contain large amounts of copper. It bonds well with the wood; does not corrode easily and pliable for a heavy metal. Although some treatments do contain tin or iron, copper remains the metal ingredient of choice when used for treating deck lumber.
The Best Metal Flashing for Your Deck
Because copper is widely used as a metal ingredient for deck lumber treatment, it is also an excellent choice for metal flashing that will be attached to your deck. With copper, there is seldom a chance of the metal not being compatible with the deck lumber or reacting with the pressure-treated lumber.
Older types of aluminum or galvanized flashing are fine for decks that are made out of standard lumber; however, they are usually not recommended for use with pressure-treated lumber that used copper in the treatment process. This is because aluminum or galvanized flashing will react with the copper in the pressure treated lumber and will usually corrode or rust much faster than it should. So, if you are using pressure-treated lumber, it is probably a good idea to use copper. Even if the wood was treated with a metal element other than copper, the copper flashing will still perform well and not corrode as fast as aluminum or galvanized flashing.
Exceptions to the Copper Flashing Rule
As stated above, if you are using wood that was not pressure-treated for your deck (albeit it is not recommended to do so), you can use aluminum or galvanized flashing without any problems. Also, if the wood was treated with another metal element such as tin or iron, then the older types of flashing should work well also.
Because copper is considerably more expensive than aluminum or galvanized tin, it is more economical to use the cheaper types of flashing for some applications. However, in order to get pressure-treated lumber that was not treated using a copper-based treating liquid, you may need to special order the lumber from a lumber yard.