Anchoring a Pergola to a Patio

A patio pergola adds shade and a place for climbing plants.

A pergola built on a patio requires an anchoring system that stands up to strong winds along with the occasional bump from furniture or people. Adjustable post brackets come in different forms and use 1/2-inch fasteners to hold them to the concrete. Nails connect the bracket to the pergola posts. The adjustable post brackets have the added benefit of lifting the post off the ground, protecting it from rot.

Things You'll Need

• Hammer drill
• 1/2-inch masonry hammer bit
• Adjustable post brackets
• 1/2-inch concrete anchor bolt
• 3/4-inch socket or open-end wrench
• Pergola posts
• Post level
• 10d 3-inch nails
• Hammer

Instructions

1. Mark the locations of the posts your pergola will stand on. These are usually either 4-by-4 or 6-by-6 posts.

2. Install the masonry bit in the hammer drill and set the drill for hammer action. Place the point of the masonry bit on a mark and squeeze the trigger enough to start the drill. Increase the drill speed gradually as the bit begins to drill into the concrete. Continue drilling until the hole is 4 inches deep or you drill entirely through the concrete.

3. Place an adjustable post bracket over the hole. Insert a 1/2-inch concrete lag bolt into the hole and turn it clockwise with the socket wrench to tighten it. Orient the bracket to match the post orientation as you finish tightening the lag bolt.

4. Stand the post up in the bracket and place the post level on the post. Hold the post so both vials on the level have a centered bubble. Nail through the bracket into the post using one nail for each provided nail hole. Repeat the process for each pergola post.

Tips & Warnings

• Once the bracket is fastened to the concrete, you have some leeway for adjustment by loosening the anchor bolt and moving the bracket.

• Check with your local building code authority. Some have specific requirements for anchoring posts to concrete patios.

• Wear eye protection and a dust mask while drilling into the concrete.

References

• Trellises Arbors & Pergolas; Better Homes and Gardens
• Simpson Strong-Tie Company: Adjustable and Standoff Post Bases

Resources

• The Family Handyman: How to Build a Pergola