How to Build a 10x10 Pergola with Steel Brackets (Step-by-Step)

A 10x10 pergola is the perfect size for a patio, a hot tub, a small seating area or a grill corner — big enough to feel like an outdoor room, small enough to build in a weekend. With heavy-duty steel brackets doing the hard part (strong, square joints), there's no notching posts and no complicated joinery. Here's how to build one with standard 4x4 lumber, start to finish.

Time: about one weekend with two people
Skill level: beginner to intermediate DIY

What you'll build

• 4 posts (4x4) standing in steel base brackets
• 4 beams (4x4) connected to the posts with 3-arm steel corner brackets
• Rafters (2x6) across the top for shade and that classic pergola look

Steel brackets you'll need

• 4 × Heavy-Duty Pergola Corner Brackets for 4x4 Posts (3-Arm, 90°) — one for each top corner
• 4 × Foot & Wall Mount Base Brackets for 4x4 Posts — one under each post
• Optional: Sun Sail Attachment Brackets (4-Pack) if you want to add a shade sail

Every bracket is 11-gauge U.S. steel with an outdoor powder coat finish, made in the USA — and shipping is free on every order.

Lumber & hardware

• 4 posts: 4x4 pressure-treated or cedar, 8 ft (about 8 ft of clearance once standing)
• 4 beams: 4x4, 10 ft long (you'll trim to fit — see Step 5)
• Rafters: about 8 × 2x6, 12 ft long, for 16-inch spacing with a short overhang on each side (or 6 rafters at 24-inch spacing)
• Fasteners for the brackets: exterior-rated lag screws or structural screws that fit the 5/16" holes
• Anchors: concrete anchors rated for outdoor use (for a slab or footings), or structural screws/bolts if mounting to deck framing
• Rafter fasteners: exterior structural screws or hurricane ties
• Exterior stain or sealer (optional)

Tip: bring one bracket with you when you buy lumber and test the fit. Wet pressure-treated lumber can swell and may not slide in easily.

4x4 or 6x6? 4x4 lumber is lighter, cheaper and easier to handle, and works well for a simple 10x10 shade pergola. If you're adding a heavy roof, a swing, or you get heavy snow or wind, build it with 6x6 lumber and our 6x6 brackets instead.

Tools

• Drill/impact driver and socket set
• Circular saw or miter saw
• Tape measure, speed square and a 4-ft level
• String line and stakes or marking paint
• Hammer drill and bit (for concrete anchors)
• Two sturdy ladders, scrap 2x4s for temporary braces, clamps
• Safety glasses, gloves — and a helper

Step 1: Plan your spot (and check the rules)

Pick a level area with room to work around all four sides. Before you buy anything, check with your city or county and HOA about permits, setbacks and height limits — rules vary a lot by area. Also call 811 before digging so underground utilities are marked.

Step 2: Lay out a perfect square

Mark the four post locations about 10 feet apart. Then measure corner to corner both ways. When the two diagonals match, your layout is square. For a 10x10 layout, each diagonal is about 14' 1-11/16". Adjust the corners until both diagonals are equal.

Step 3: Set the base brackets

The base brackets mount the posts on top of a solid surface, so the wood stays off the ground.

• On a concrete patio: make sure it's thick, solid and in good shape. Set each base bracket on its mark, drill and anchor it with outdoor-rated concrete anchors.
• No patio? Pour a concrete footing at each corner first. Footing size and depth depend on your soil and frost line — your local building department can tell you what's required. Anchor the base brackets once the concrete has cured.
• On a deck: fasten into solid framing (joists or blocking), not just deck boards.

Re-check your diagonals before the last anchor goes in.

Step 4: Stand the posts

1. Cut all four posts to the same length with square ends.
2. Set each post into its base bracket and fasten it through the bracket holes.
3. Check plumb on two sides with your level, then brace each post with two scrap 2x4s staked to the ground.

Step 5: Add the corner brackets and beams

1. With a helper, set a 3-arm corner bracket on top of each post, with the two arms pointing toward the neighboring posts. Fasten it to the post.
2. Dry-fit before you cut. Measure between the bracket arms on each side, then trim your 10-ft 4x4 beams to fit snugly. Measure each side separately.
3. Lift each beam into the bracket arms with a helper. Check that it's level, then fasten through the bracket holes.
4. Check your diagonals one more time across the top before tightening everything down.

The steel brackets lock every corner at a true 90°, so once the beams are in, the frame gets noticeably stiffer. Leave the temporary braces on until the rafters are installed.

Step 6: Install the rafters

1. Mark rafter spacing along the top of two opposite beams — every 16 inches on center for more shade, or 24 inches for a more open look.
2. Set the 2x6 rafters on edge across the beams, with an even overhang on both ends. A decorative angled cut on the rafter ends gives it a finished, custom look.
3. Fasten each rafter to the beams with exterior structural screws or hurricane ties.

Step 7: Finish it

• Remove the temporary braces and re-check every fastener.
• Stain or seal the wood once it's dry enough (pressure-treated lumber often needs a few weeks to dry out first).
• Want more shade? Add a shade sail with our sun sail brackets, or lay 2x2 slats across the rafters.

Want a bigger pergola?

See our step-by-step 12x12 pergola guide, built with 6x6 lumber. For longer spans, add a center post and use a T-bracket center support or a 4-way center support.

Need help choosing?

Tell us the size you want to build and your post size, and we'll help you pick exactly the right brackets. Contact us — no question is too small.

This guide is general information for DIY builders. Always follow your local building codes and the instructions that come with your materials and fasteners.