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How to Install Deck Flashing

Step-by-Step Guide: Installing Deck Flashing for a Stronger and Safer Deck

Installing deck flashing is an essential step in protecting your deck from water damage. Flashing is a thin, waterproof material that is installed between the deck ledger board and the house. It prevents water from getting behind the ledger board and causing rot or other damage to the structure of your deck. Here’s a step-by-step guide on how to install deck flashing.

Step 1: Prepare the Ledger Board
Before you begin installing deck flashing, you need to prepare the ledger board. Remove any old flashing or debris from the area where you will be installing the new flashing. Make sure the area is clean and dry.

Step 2: Measure and Cut the Flashing
Measure the length of the ledger board where you will be installing the flashing. Cut the flashing to the appropriate length using tin snips or a metal cutting blade.

Step 3: Install the Flashing
Slide the flashing up behind the siding and over the top of the ledger board. Make sure the flashing is flush with the ledger board and the siding. Secure the flashing in place using roofing nails or screws. Space the nails or screws about 6 inches apart along the top edge of the flashing.

Step 4: Seal the Flashing
To ensure that the flashing is completely waterproof, you need to seal it. Apply a bead of silicone caulk along the top edge of the flashing where it meets the siding. Smooth the caulk with your finger or a caulk smoothing tool.

Step 5: Check for Proper Drainage
Once the flashing is installed and sealed, check to make sure that water will drain away from the ledger board and the house. Use a hose to simulate rain and watch where the water flows. If it pools anywhere, adjust the flashing as needed.

Step 6: Repeat for Additional Ledger Boards
If your deck has multiple ledger boards, repeat the above steps for each one. Make sure that each flashing overlaps the previous one by at least 2 inches to ensure proper water drainage.

In conclusion, installing deck flashing is a crucial step in protecting your deck from water damage. Follow these steps carefully to ensure that your flashing is installed correctly and will provide the necessary protection for your deck.