If you’re building a pergola, one of the first steps is installing your pergola post brackets.
While you can install simple footings and put the posts directly into the concrete, many experts recommend installing post brackets. Brackets, which keep the wood out of the concrete, extend the life and support of the posts.
This tutorial will walk you through the straightforward process of installing brackets into concrete for mounting 6×6 pergola posts.
For 6×6 pergola posts, you’ll need 12” concrete forms.
Before digging, check your zone for the freeze depth to determine how deep your concrete support needs to be. In our zone, this is 30” deep. Use a hand saw to cut the 12” concrete form to size. Then, place the form into your dug hole.
Run strings as needed to determine your post’s placement and/or alignment, then check the bird’s-eye view of the strings.
Depending on the type of your bracket, ensure the piece you’ll place into the concrete are in the inner third of your concrete form. In this example, the 6×6 brackets have a central post.
As you can see on the second form, the bracket post will not be in the inner third of the concrete form, so the hole needs to be dug out and moved to the right.
Use a pry bar and/or shovel to make the hole bigger on that side. Clear out the dirt.
Place the concrete form back into the hole and check for the bracket placement. This is better; as you can see, the post is in the safe zone. Getting the post in the direct center is best, but not always possible.
Spray an inch or two of water into the bottom of your concrete form.
Pour some bags of fast-setting concrete into the form. (Add a little water in between each bag if you want.) It’s important to find a concrete mix that is specifically for posts; this allows you to mix directly in the hole rather than having to pre-mix in a bucket or wheelbarrow.
Use the pry bar in an up-and-down movement to mix the powder and water. Remember that this concrete is fast-acting, true to its name, so mix it thoroughly but quickly.
Add water or small amounts of powder until the top is a semi-solid mixture that will hold the bracket in place. It doesn’t need to be perfect, but the concrete must support the bracket as it sets and dries.
When the concrete is ready, tie a very small weight at the bottom of a small string. Then, attach it to the corner joint of your strings.
Gravity will work in your favor, giving you a third line for “leveling” the bracket – two up top at the bird’s-eye view, and one hanging down.
Immediately push the bracket into the concrete in its desired placement. Adjust as needed, but time is working against you, so be quick.
When your bracket is positioned, use a small hand shovel to press concrete tightly up against the bracket post.
You can slope the concrete away from the bracket post or smooth it flat if you’d like. Check everything for level one last time, then leave the bracket alone while the concrete dries.
You’ve now finished one of the most important steps in building a pergola. When the concrete is completely dry, you’ll be ready to mount your pergola posts.