Building a Custom Cedar Pergola

PERGOLAS turn a flat, sun-drenched patio into an architectural room. Unlike a solid roof, a pergola offers a soft, dappled light that keeps the space airy while defining the outdoor living zone as a distinct destination rather than just a slab of concrete. Success here relies on heavy-duty hardware and precision in your layout. A pergola is essentially a large frame that catches a lot of wind, so every connection needs to be square, level, and bolted to last through heavy weather. When done well, it stands as a permanent, sculptural element of your landscape that frames your view and invites you to spend more time outside.

Square Your Layout First. Measure the footprint of your structure, marking the corners with batter boards and string lines to ensure a perfect rectangle. Verify the layout by measuring diagonally; the diagonal measurements must be identical for the structure to be square.
Anchor Posts Perfectly Plumb. Dig post holes at least 30 inches deep, or install surface-mount post bases onto an existing concrete slab using heavy-duty masonry anchors. Ensure the posts are plumb on both faces before securing them firmly.
Bolt Beams Rock Solid. Bolt two 2x10 beams to opposite sides of each post pair using carriage bolts. Use a temporary bracing board to hold the beams level while you drill the through-holes for the bolts.
Lock Rafters Into Place. Cut notches in your 2x8 rafters to sit snugly over the support beams, spacing them evenly across the length of the structure. Secure each rafter to the beams using galvanized structural screws or metal rafter ties.
Lay Slats For Shade. Lay 2x2 cedar slats perpendicular to the rafters across the top of the structure, spacing them 6 to 12 inches apart. Screw each slat into the rafters to create the final grid that provides the shade.
Seal Every Surface. Apply a high-quality exterior wood stain or clear UV-protectant sealer to all surfaces. This prevents the cedar from turning gray and protects the joints from moisture infiltration.