Cutting Beams For A Pergola
A pergola can be as simple as a lean-to attached to an exterior wall or as complex as a large free-standing, four-side trellis walled garden arbor. When you need to cut beams for a pergola, some basic carpentry skills and a little guidance will get you through the task.
Step 1: Against the Wall
If attaching a pergola against an exterior wall to cover a patio, first attach a “ledger” board to hold the pergola beams. Since the ledger needs to be the first pergola beam installed and the size of the pergola will cover the patio, first measure the patio width against the wall to use this plus 2 inches on either side for your cutting measurement. Wearing safety goggles use a circular saw to cut the 2 X 6-inch ledger beam to the appropriate length laying it across a pair of sawhorses.
Step 2: Notch the Ledger
Here is a technique that eliminates the need for any metal brackets or toe-nailing to attach the pergola beams that will run from the wall out to the edge of the patio. Place the beams at 12-inch intervals. Then begin notching the ledger board 2 inches from the ends and then every 12 inches, using a jigsaw. Make sure you cut out a 2-inch notch for each beam.
Step 3: Cut the Long Beams
After measuring from the inner edge of the ledger beam out to the edge of the patio, add 2 inches and cut the number of needed pergola beams from 2 X 6 lumber. Use a jigsaw to cut a notch at the end of each 2 X 6 pergola beam to fit into the notch cut out on the ledger beam that will be attached to the exterior wall. Insert the first notched beam into the notch cut out to see that it fits snugly and securely. Adjust the notch cuts with either the jigsaw or by sanding it to make the fit.
Step 4: Cut the Crossbeams
Measure a number of cross beams that will run in the opposite direction of the long beams that were cut and notched. These should be 6 inches longer than the measurement from post to post. Now measure the distance where each long beam comes in contact with a cross beam to cut notches on the crossbeams to secure these to your long beams. Use either a dado blade on a table saw or circular saw to cut out the notches laying the beams across a pair of sawhorses.
Step 5: Brace Cuts
Each support post will need braces cut from 2 X 6 lumber. Using a circular saw, make a 45-degree angle cut on both sides to fit between the post edge and outside beam.
Paint or stain your cut pergola beams before installing.