How to Repair Concrete Deck Anchor Bolt

By Robert Robillard on Decks And Porches

How To Replace A Deck Footing Threaded Bolts

Even the best carpenters I know sometimes pour a footing that is off or place the threaded J-bolt [anchor bolt] in the wrong location.  This article will show you how to repair concrete deck anchor bolt when placed in the wrong location.

How to Repair Concrete Deck Anchor Bolt

Threaded Anchor Pin Not Centered

Concrete Footings and J-Bolts

Concrete deck footings and piers are designed to support the weight of a deck.   In a perfect world deck posts are supposed to rest securely and centered on these footings with a threaded anchor or J-bolt holding it down.  Anchor bolts are designed to resist post movement and deck uplift from high winds.

Most deck footings these days are either poured in place or precast and then hoisted down into an excavated hole.

When poured in place most folk s use “Sono-tubes” or an equivalent concrete form.  These forms are simple to use, easy to install resist settling, uplift caused by frost and result in a stronger deck footing.

What To Do With Misaligned Anchor bolts

Many times the anchor bolts used in the concrete forms are neither centered nor lined up properly and need to be redone in order to properly secure your deck post to the concrete footing.

Using galvanized, adjustable post base plates allow 1/2-inch discrepancy in any direction if you have made an error when placing footing anchor bolts.

Sometimes 1/2-inch is not enough as everything needs to line up as precisely as possible.  Even with adjustable post bases you sometimes have to cut your losses and start over.

How to Repair Concrete Deck Anchor Bolt

Starting Over – New Anchor Bolts

Once you’ve come to the conclusion that the anchor bolt you have is in the wrong location and it needs to be removed, you can get started fixing it.

  1. Start by cutting, the misaligned anchor bolt flush to the footing, with a reciprocating saw and a metal cutting blade.
  2. Use a level, plumb bob or a laser to identify the location of your new anchor bolt.
  3. I use a level to plumb down from the deck rim joist  to locate my post base connector.
  4. Use a pencil to mark two sides of the post base connector on the footing.
  5. I use galvanized wedge anchors but you could also use epoxy and galvanized threaded rod.
  6. Wedge Anchors are designed to anchor objects into concrete. They are installed into a pre-drilled hole, and then the wedge is then expanded when the nut is tightened.  The wedge secures the anchor in the concrete.
  7. Pre-drill this hole with a rotary hammer drill and remove the dust from the hole after drilling.
  8. Place your adjustable post base on the footing and centered over the new hole.
  9. Tap the wedge anchor into the hole with a hammer.
  10. Remember to have the washer and nut installed and flush with the top of the anchor bolt. Failure to do so may result in the hammer damaging the anchor threads and prevent you from attaching the nut.
  11. Once the bolt is flush to the post base connector and footing line up the connector and tightens the bolt.
  12. Cut your pressure treated post to size and install it on top of the post base connector and under the beam or rim joist of the deck.
  13. Plumb post.
  14. Attach all code required post to footing and post to beam connectors and add code compliant fasteners to secure them in place

 TIP: Threaded studs are an alternative to J-bolts and you can install them after the footings have cured.   Using this method could reduce errors.

By following these simple directions you are well on your way to learning  how to repair concrete deck anchor bolt when placed in the wrong location and having a safe and healthy deck!



If you enjoyed this post, make sure you subscribe to my RSS feed!

About the author

Robert Robillard

Carpenter / Remodeler / Editor

Rob Robillard is “The Concord Carpenter” Rob is a builder, general contractor, carpenter, woodworker, and editor of Concord Carpenter and ToolBoxBuzz As a General Contractor and carpenter, Rob owns and operates Concord Carpenter LLC. A full-service remodeling and construction company. Rob is a recognized leader in home building best practices and a source for how-to information for building professionals. On this website, Rob covers all aspects of home construction, building science, home improvement, woodworking, remodeling, and some of the best product and tool reviews. Rob is in charge of our Tool and Product Review series - Concord Carpenter Videos where we post all of our tool reviews and video tutorials. Rob approaches remodeling and building construction with a pragmatic and problem-solving approach. He enjoys using his knowledge and experience to help and educate building professionals as well as DIYers on best practices in the construction and remodeling industry. He's a strong advocate for "raising the bar" in the construction trades and promoting the trades to youth. #BeAMentor #Green2Great Craftsmanship, quality, and pride guide his journey on this channel The Concord Carpenter's motto: "Well done is better than well said!" : Read more about Rob

All posts by Robert »

Not what you're looking for?

Search for more articles here. Enter keywords like roof leak, bookcase, deck, etc to find your topic.

© Copyright 2019 A Concord Carpenter · All Rights Reserved