When and How to Use J Bolts

anchor plate mounted to the ground
  • 2-5 hours
  • Beginner
  • 100
What You'll Need
Concrete
Concrete float
Tape measure
J bolts
What You'll Need
Concrete
Concrete float
Tape measure
J bolts

J bolts are a very common and durable fastener that many contractors use when erecting a new building. Homeowners can also use the threaded fasteners when building a garage, building a new foundation, or simply attaching a new wall to concrete. J bolts are readily available in many hardware stores and look just like their name suggests. They have a long end, which can be in different lengths, which is threaded with a hook on the other. Thus the resulting look is like a 'J'.

Step 1 - Pour Wet Concrete

In order for J bolts to be used correctly, you will need to insert them into wet cement. This type of bolt is great for deck supports, the bottom sill of a 2 x 4 frame home construction, or joining a new concrete wall to a previous one. However, the installation always necessitates wet cement. The threads stick up through the cement so that the bolt can be tightened to hold the sill in place. Before you set out any J bolts you will need to pour the wet cement into place.

Step 2 - Smooth Wet Cement

Once the wet cement is poured into the form or footing, you should then smooth it out with a concrete float.

Step 3 - Measure for J Bolts

tape measure, calculator, and blueprints on a table

Looking at the blueprints of your new building, locate the positioning of the anchor bolts. Use a tape measure and mark positions for the J bolts with a small scratch on the concrete. J bolts should be positioned at least two inches in from the edge of any slab. They can be located anywhere on a footing for a deck.

Step 4 - Insert J Bolts

Hold the J bolts in your hand. With the hook at the bottom of the bolt insert it into the wet concrete at a slight angle. Wiggle the bolt a little to get rid of any air bubbles. Stand it straight up and move onto the next bolt. Continue with this process until all the bolts are installed. Smooth out the concrete around the bolt with a small float. You will need to continually check the J bolts until the concrete has dried to make sure they do not tilt or settle into the concrete.

Step 5 - Work in Tandem

concrete foundation

If you have a large footing or concrete slab, you should have another person working with you to make sure the concrete does not dry too much before you get the bolts in. As one person uses the float to smooth out the edges of the concrete slab, the other can be installing the J bolts.

Step 6 - Drill into Concrete Wall

If you have to join a new wall with an older one, then you will need to drill into the wall. Use a hammer drill with a mortar bit and drill into the wall where the J bolt will go. Set the threaded end into the wall and then pour new concrete into the form. The concrete will dry over the J bolt locking the two sections into place.