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Can You Use Aluminum Flashing with Pressure Treated Lumber?

After spending time and money to create a great new wooden deck for your home, it is time to think about the flashing. While there are different materials you can choose for the flashing, you need to pick one that is sturdy and will last because this helps keep moisture away from the treated wood that you have on the deck. This may lead you to wonder if you can use aluminum flashing to complete the job. 

Can You Use Aluminum Flashing with Pressure Treated Lumber?

Yes, you can use aluminum flashing with pressure treated lumber. This is one of the most common types of flashing to use on decks and other areas of the home. Use caution when choosing to use this with lumber treated with copper because it may cause the aluminum to corrode faster than expected. 

There are different types of flashing that you can use with your treated lumber, but aluminum is still one of the most common. Let’s take a closer look at what aluminum flashing is and how it can be used on your pressure treated lumber. 

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Using Aluminum Flashing with pressure Treated Lumber

using aluminum flashing on pressure treated wood

Yes, it is possible to use older types of aluminum flashing to help with your deck or other items made out of pressure treated wood. However, you should be careful if the lumber used any copper in the treatment. This can affect the final result and may not make it look as nice as you would like. The reason for this is the aluminum flashing will react with the copper that is in the pressured wood and can corrode or rust faster than expected. 

What this means is that if you plan to use pressure-treated lumber, it is usually recommended to work with copper compared to aluminum. Even if you treat your wood with a different type of metal than copper, the copper flashing often performs well and will not end up corroding as fast as aluminum flashing will, preserving the look and feel of your deck along the way. 

What is Aluminum Flashing?

To help understand why you would use aluminum flashing or another option, it is important to take a look at what this is. Aluminum flashing is simply a continuous piece of metal that is meant to prevent water getting through an angle or a joint. The idea with flashing is that it is supposed to provide a good barrier over any area where water is likely to penetrate, preventing water getting inside. 

When used on your deck, this flashing is used to protect the treated wood. It will protect some of the areas that are likely to get the most water through them. This will ensure that the wood stays strong and water can’t erode the area. Aluminum flashing is a popular option for this, but there are many other types of flashing available including:

  • Copper
  • Stainless steel
  • Galvanized steel
  • Lead-coated copper
  • Zinc alloy. 

Despite all of these choices, aluminum flashing is still one of the best options to use for many reasons. Depending on the type of treated wood you have, it may be the first choice you go with too.

Should You Use Aluminum Flashing?

Aluminum flashing is one of the most common types of flashing that you will see on decks and with other options for pressure treated lumber. It is inexpensive and easy to install when necessary. This type of flashing is often soft and workable, meaning that it is easy to install and will hold its shape. It is not always as strong as some of the other flashing options that you may choose though. 

Depending on the manufacturer you use, you may even be able to choose the color of it to match your home. While regular aluminum without the color can work fine for treated wood projects like your deck, it can be nice if you choose to use this type of flashing on your roof or somewhere else on the home. 

Aluminum flashing is one of the most common types that are used on treated lumber, including for decks and other parts of the home. It doesn’t cost all that much, it can last for a decent amount of time if you take care of it well, it looks nice, and it will do the job of keeping the moisture and water away from the treated lumber. 

When Should You Avoid Using Aluminum Flashing?

While there are benefits to using aluminum flashing on treated wood, there are some drawbacks as well. First, after using the aluminum, you will need to coat it to make sure it has a direct contact with the wood. This will add to the cost that you will need to spend. You will need to price this out to make sure that it is the right option for you. 

Another problem will come with the type of treated lumber you will use. If copper is used in the process, the copper and aluminum may not react well to one another at all. In fact, the copper is likely to make the aluminum corrode faster than before, which means you will need to replace the flashing sooner than you expect or it will cause damage to the treated lumber. 

Should You Consider Using Copper Flashing Instead?

If you do use a lumber that was treated with some kind of copper, it is usually best to avoid aluminum flashing, unless you plan to replace it often. Copper flashing is a good substitute. It will not corrode or have an adverse reaction to the copper that is inside of the treated lumber, providing extra protection to the wood that you would not be able to get anywhere else. 

The aluminum flashing is not necessarily bad to use here and there are still many contractors and homeowners who like the look and feel of the aluminum instead of the copper. Just be aware that it may not last as long and you will need to check up on it often to ensure it still looks nice and performs well. 

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