- 1). Locate and mark any underground utilities. Clear all debris from the pergola site and level the area if it is uneven.
- 2). Mark the front edge of the pergola using a 2-foot-by-2-foot board. Place a stake at the front right corner. Attach a string to the stake.
- 3). Position an oversized triangle on the front edge board at a 90 degree angle. Run the string 72 inches to the back corner. Adjust the string until the front-right corner is 90 degrees. Mark the back-right corner with a stake and string. Continue this process to each corner of the pergola, joining the stakes with string. This will form the six-foot outline of the pergola.
- 4). Place a bucket, with its bottom removed, centered on each post and outline it with chalk. This will mark the area to dig for each hole.
- 5). Using a post-hole digger, dig out a hole for each post measuring 1 foot wide and 2 feet deep.
- 6). Pour a 3-inch layer of crushed gravel into each hole. This will help with drainage. Place posts in the holes, one at a time. Attach temporary braces with clamps to the poles so they stand alone. Use a pole level and make adjustments until the pole is plumb. Repeat this process with all four poles.
- 7). Pour quick-setting concrete and one gallon of water into each hole. Wait about 10 minutes for concrete to set before proceeding.
- 8). Working on one side, fix temporary horizontal braces to support the chamfered beams that will run on either side of each side post. Pre-drill two holes for the carriage bolts. These will join the chamfered beams to the posts. Stagger these holes to avoid splitting the post. Repeat this process on the opposite side.
- 9). Using a metal mallet, drive the carriage bolts through the pre-drilled holes. Secure washers and nuts to the carriage bolts on the outside of the pergola.
- 10
Attach crossbeams perpendicular to the side beams with braces and galvanized nails at equal distances on top of the pergola structure.
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