How to Extend a Deck Joist: A Step-by-Step Guide

So, you’ve been enjoying your deck for years, but now you’re thinking it’s time for an upgrade. Maybe your family has grown or you just want more space to entertain guests. Whatever the reason may be, extending a deck joist can seem like a daunting task. But fear not! In this blog post, we’ll walk you through the process step by step, so you can confidently extend your deck and have it ready in no time.

Tools and Materials You’ll Need

Before we get started with the instructions, let’s make sure you have everything you need. Here is a list of tools and materials required for this project:

  1. Tape measure
  2. Circular saw or handsaw
  3. Hammer and nails (or screwdriver and screws)
  4. Drill with various-sized bits
  5. Wood glue
  6. Joist hangers
  7. Lumber (same size as existing joists)
  8. Level
  9. Carpenter’s square

Once you’ve gathered all of these items, it’s time to get started!

Planning Your Deck Extension

The first thing you’ll need to do is decide how big of an extension you want on your deck.

Measure out the distance from the edge of your current deck to where you want the new section to end. Keep in mind that depending on your local building codes and regulations, there may be limits on how far out your deck can extend past its current footprint.

Next, determine whether any additional support posts will be needed for this extended area. You should consult local building codes or speak with an engineer before making any decisions regarding support posts.

Now that we’ve got our plan in place let’s move on to extending those joists!

Preparing Your Existing Joists

Before attaching any new lumber to existing joists, it’s essential to make sure they’re in good condition.

  1. Inspect the existing joists for any signs of damage or rot.
  2. If you find that some joists need replacing, now is the time to do so.
  3. Make sure all existing joist hangers are securely fastened and not rusted.
  4. Replace any faulty hangers if necessary.
  5. Clean off any dirt or debris from the top edge of your joists.

Cutting Your New Joist Extensions

Now that your existing joists are prepared, it’s time to measure and cut your new extension pieces.

  1. Measure the length needed for each extension, based on how far out you want your deck to extend.
  2. Keep in mind that it’s always better to cut a bit longer than needed – you can always trim later if required.
  3. Using a circular saw or handsaw, carefully cut each extension piece from your lumber.
  4. Ensure each piece is straight and square by using a carpenter’s square during this step.

Attaching Your Joist Extensions

Once all pieces have been measured and cut, it’s time to attach them!

  1. Apply wood glue along the side of one of your new extension pieces, making sure it covers the entire length where it will be joined with an existing joist. This will help create a strong bond between old and new lumber.
  2. Line up the glued edge of the extension with the end of an existing joist, making sure both ends are flush against one another.
  3. Use nails or screws (depending on what was used on your original deck) spaced approximately 12-16 inches apart to secure these two pieces together. Make sure they penetrate through both layers of wood without splitting either piece.

Repeat these steps for all remaining extensions until every joist has been extended properly.

Installing Additional Support Posts (if needed)

If your deck extension requires additional support posts, now is the time to install them.

  1. Determine the locations where new support posts will be needed based on your earlier planning.
  2. Dig holes for each post, ensuring they’re deep enough to accommodate any required concrete footings. Consult local building codes for specific depth and footing requirements.
  3. Set each post in its hole and ensure it’s level vertically. Use a level throughout this process to make sure everything stays straight.
  4. Secure the posts with concrete or other approved methods as per local regulations. Allow time for any concrete to cure before proceeding.

Adding Joist Hangers

Now that all joists have been extended, it’s time to secure them with joist hangers.

  1. Measure the distance between each joist along the ledger board (the board attached to your house). This should match the spacing of your existing joists.
  2. Attach a new joist hanger at each measured location along both ends of every extended joist.
  3. Ensure all hangers are level and securely fastened into place using appropriate nails or screws.

Final Checks & Decking Installation

Before installing decking on top of your newly extended deck frame, it’s essential to double-check that everything is square and level.

  1. Use a carpenter’s square at every corner of your deck frame to ensure all angles are 90 degrees.
  2. Make adjustments as needed by shifting joists or adding shims under low points.
  3. Check that all extended joists are level across their length using a long straightedge or string line.
  4. Adjust as necessary by raising or lowering individual sections until everything is even.

Once you’ve verified that everything is square and level, you can proceed with installing decking boards on top of your newly extended deck frame following standard installation procedures!

How To Extend A Deck Joist Conclusion

And there you have it – an expertly extended deck joist, ready for your enjoyment. Now go ahead and enjoy your extra space for relaxing, entertaining, or whatever else you’ve been dreaming of doing on your newly expanded deck!