Deck Joist Flashing Tape: What You Need to Know

November 13, 2020
HomeOutdoor Living IdeasDeck Joist Flashing Tape: What You Need to Know

Deck joist flashing tape is used to protect your deck’s substructure – commonly made with traditional lumber – from moisture. As an organic material, traditional wood is highly vulnerable to mold, mildew, and rot. An effective and affordable way to protect your deck’s substructure is by using tape for your joists.

A healthy substructure is essential for the overall health of your deck and benefits you by:

  • Saving you on future maintenance/replacement costs.
  • Increasing the anticipated life of your deck.
  • Improving your deck’s structural integrity so you can enjoy your deck, worry-free, year after year.

What Is Deck Joist Flashing Tape?

Deck joist flashing tape is a water-resistant butyl adhesive used to keep moisture from penetrating your deck’s frame. While TimberTech composite deck boards are weather- and moisture-resistant, the traditional lumber used for the joists and ledger is susceptible to water damage.

Deck Joist Flashing Tape protecting theTimberTech Deck Substructure

Joist Tape: Why It’s Essential & When to Use It

In order to protect your deck’s substructure from weathering and moisture, protective tape for your joists is a must.

Benefits of Deck Joist Tape Flashing Tape

  • Prevents moisture penetration of joists.
  • Protects the lumber from rot.
  • Extends the life of the deck’s substructure.

When to Use Deck Joist Flashing Tape

  • Prevents moisture penetration of joists.
  • Protects the lumber from rot.
  • Extends the life of the deck’s substructure. 

TimberTech composite decking is designed for durability and lasting beauty, with our TimberTech® AZEK® line boasting a Lifetime Limited Product Warranty. When you invest in high-quality composite decking designed to last a lifetime, it’s essential that your substructure lasts just as long.

Joist and flashing tape can ensure your deck’s substructure retains its integrity and strength so you and your family can confidently enjoy your deck for years to come.

Not Sure How to Space Your Joists? Find out all you need to know about joist spacing and blocking including the tools and materials needed, installation steps, and more. DIY: JOIST SPACING.

How Do I Use Deck Joist Tape?

If you’re building your own composite deck, applying tape should be one of the easier steps to complete.

Protect Deck Joists With Deck Joist Flashing Tape

Some best practices for applying the tape to your joists include:

  • Apply the tape to clean, dry lumber.
  • Use firm pressure (preferably with a hand roller) to ensure adequate adhesion.
  • Try to avoid wrinkles or air bubbles, as these will allow moisture to seep in.

Joist and Flashing Tape Extends the Life of Your Deck

TimberTech® PRO-Tac™ Flashing and Joist Tape is designed with durability in mind, so your substructure can last just as long as your TimberTech composite deck.

Deck Joist Flashing Tape TimberTech PROTac Flashing & Joist Tape Roll Liner

Deck Joist Tape Designed to Last

TimberTech PRO-Tac Flashing and Joist Tape provides superior, long-lasting protection for your deck’s substructure.

  • Butyl rubber adhesive provides a secure bond with zero oozing (unlike asphalt adhesive).
  • Superior peel adhesion creates a tight seal, so moisture won’t rust nails or work its way into the wood.
  • Won’t bunch, bind, or tear during screw driving.
  • Heavy-duty backing means this tape won’t tear easily, even when walking on or dragging boards across the joist.

Now that you understand just how important deck joist flashing tape is to your deck build, don’t omit it. Grab TimberTech PRO-Tac Flashing and Joist Tape to protect your deck’s frame with the best of the best.

As you know, building a deck takes so much more than proper application of tape to your joists. Working with a TimberTech-registered contractor ensures you get a safe, beautiful, and long-lasting deck that you can enjoy year after year.

Bring the Beauty of TimberTech to Your Backyard

Work with one of our registered contractors for a build that transforms your outdoor living space.

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