Protect your deck from joist rot

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A little diligence and an inexpensive deck flashing tape keep things protected and help prevent deck joist rot.

Grace flashing tape

Last summer, I helped a carpenter buddy tear out a rotten deck. The joists were pressure-treated lumber, so I was surprised at how badly decayed they were. But my friend wasn’t. He sees it all the time: deck joists rotting from the top edge down because the deck boards and debris keep them damp for weeks after rain. So he has two rot-fighting tips for deck owners and builders:

1. Take a few minutes occasionally to pull out the leaves, twigs and other debris that gathers between deck boards, especially where the decking crosses joists. A drywall saw works great for this.

2. If you’re building a new deck, cover the joists with rubbery, adhesive-backed “flashing tape.” This will add $50 or more to the cost of your deck, but that’s cheap insurance to prevent deck joist rot. You can purchase deck flashing tape or other items through our affiliation with Amazon.com: Grace Deck Protector 45639 Felt Asphalt Rolls

— Gary Wentz, Senior Editor

Image provided by Grace

Related articles from The Family Handyman:
Rebuild an old deck with new decking and railings
7 Deck building tips
How to build deck stairs
Low-maintenance decks

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