How to Safely Attach a Deck to a House | This Old House

Introduction

In this tutorial, you will learn how to safely attach a deck to a house to prevent catastrophic failures, such as collapses caused by poor construction practices. This guide will walk you through the necessary tools, materials, and steps required to secure a deck effectively, ensuring safety and stability.

Step 1: Assess the Current Condition of the Deck

• Inspect the ledger board (the board that attaches the deck to the house) for any signs of damage or instability.
• Look for inadequate fasteners, such as nails, that may not be sufficient to support the deck.
• Check the joist hangers to ensure they are appropriately sized for the joists being used.

Step 2: Position the Deck Properly

• Use a sledgehammer to gently push the deck back toward the house.
• Ensure the deck is raised to the proper height before proceeding with the attachment.

Step 3: Secure the Ledger Board

• Materials Needed:
  • ½-inch x 10-inch galvanized lag screws with washers
• Procedure:
  • Drill pilot holes through the ledger board into the rim joist of the house.
  • Use an impact wrench to install the lag screws, ensuring a tight and secure connection.

Step 4: Add Additional Support with Masonry Bolts

• Materials Needed:
  • ½-inch x 10-inch masonry wedge anchors
• Procedure:
  • Use a hammer drill with a ½-inch-diameter masonry bit to create holes in the stone foundation.
  • Insert the masonry bolts through the ledger board and into the drilled holes, securing everything in place.

Step 5: Upgrade Joist Hangers

• Materials Needed:
  • Engineered-lumber joist hangers
• Procedure:
  • Remove the existing, undersized joist hangers.
  • Install the new, appropriately sized engineered-lumber joist hangers to provide better support for the 2x10 joists.

Additional Tips

• Always ensure that you are using pressure-treated lumber where necessary to resist moisture and decay.
• Double-check all fasteners for tightness after installation to avoid future issues.
• If you encounter any issues during the installation, consider consulting with a professional contractor for guidance.

Conclusion

Attaching a deck securely to a house is crucial for safety and stability. By following these steps—assessing the current condition, properly positioning the deck, securing the ledger board, adding masonry bolts, and upgrading joist hangers—you can prevent potential disasters. If you’re ready for more home improvement projects, consider exploring additional tutorials or seeking professional assistance.