How to Build a Garden Trellis Archway

Landscaping and garden designs are as different as the people who create them. Many gardeners look for things to add to the overall appearance of their garden, and a trellis archway is one of the ways to do that. Building a garden trellis archway provides two benefits. First, it gives you an arched walkway that you can use as an entrance marker if desired. Second, it gives you a place to grow climbing plants or vines that you may not want to put among your other plants.

Things You'll Need

• Circular saw
• Tape measure
• Two pencils
• Post-hole digger
• Quick-setting concrete mix
• Water
• String
• Combination square
• Hammer
• Level
• Shovel
• Saber saw
• Electric sander
• 120-grit sandpaper
• Safety goggles
• 3-inch deck screws
• 2 ½-inch galvanized deck screws
• 1 ¼-inch deck screws
• 2-inch galvanized deck screws
• 4d finish nails
• 4 pieces 1-by-4 inch lumber, 8 feet
• 4 pieces 4-by-4 inch lumber, 10 feet
• 15 pieces 1-by-2 inch lumber, 8 feet
• 1, 2-by-4 inch lumber, 8 feet
• 2, 2-by-12 inch lumber,12 feet
• Scrap wood
• Power drill
• Screwdriver bits

Instructions

Cutting Pieces and Arches

1. Measure, mark and cut the two 2-by-12s into four 50-inch long pieces. These are the pieces that will make the arch.

2. Measure, mark and cut nine 1-by-2s into 18 pieces with 42-inch lengths, which will be the horizontal pieces, six 1-by-2s to 69-inch lengths, which will be the vertical lattice pieces, and four 1-by-4s into seven 42-inch long pieces, which will be the roof lattice pieces.

3. Measure, mark and cut four 2-by-4s to 60-inch lengths, which will be the temporary braces, and one 2-by-4 into two 39-inch lengths, which will be the rail pieces.

4. Lay two of the arch pieces flat to form a "T" shape. Measure from the top edge of the cross piece down the trunk piece, stopping when you reach 30 inches. Mark this point, centered, and partially drive a nail into the mark. Tie one end of a piece of string to the nail and stretch the string tight. Tie the opposite end of the string to a pencil, keeping it stretched 30 inches from the nail.

5. Use the attached string and tied pencil to draw the top arch on the cross board, left to right. Cut 3 1/2 inches off the string, retie and repeat to make the bottom half of the arch. Place the combination square on each corner and mark 45-degree angles on each corner. Repeat the whole process to make three more curved arch pieces. Cut the 45-degree angles with the circular saw and the arch pieces with the saber saw. You can use the first arch as a pattern if you cut it out first and then continue with the remaining three.

Arch Assembly

1. Place two arch pieces together as left and right pieces, end to end. Place a piece of scrap wood under the butt seam and trace the arch 4 inches out from each side of the seam.

2. Cut out this piece with the saber saw to create an 8-inch long gusset to support the seam.

3. Trace the cut out gusset on another piece of scrap wood and cut it out to create a second gusset for the second arch.

4. Place all four arch pieces together, as you did previously, to create two arches-a front and back. Attach one gusset to each arch with 2 1/2-inch galvanized deck screws, lining up the form of the gusset to provide the 4-inch requirement on either side of the seams.

5. Sand both arches using the sander and 120-grit sandpaper until smooth to the touch.

Adding Roof Lattice

1. Position the arches so the gussets face each other. Place one 39-inch rail in between the bottom ends of the two arch sections. Line the edge of the rail piece up so that it's flush with the ends of the arch, standing all the pieces up on a flat surface if necessary.

2. Add two 3-inch screws to both arches to secure the rail to the arches. Repeat for the second rail and opposite ends of the arch.

3. Place one 42-inch roof lattice piece on top of both arches. Center this piece over the front and back seams and secure in place with a 2-inch screw on each end.

4. Attach the remaining six roof lattice pieces to the two arches in the same manner, spaced evenly between each other. Use the 2-inch screws.

5. Sand the roof lattice pieces until smooth.

Side Lattice Assembly

1. Measure, mark and cut the four 4-by-4s. You will need to cut your posts to a length that allows them to extend 72 inches above the ground. The depth below ground level is determined by your local codes.

2. Place two posts parallel to each other, 42 inches apart. Place one horizontal lattice piece across the two posts, four inches from the top of the posts. Attach on each end with a 2-inch screw. The ends of the lattice piece should be flush with the post edges.

3. Place your second horizontal lattice piece 8 inches from the center of the first piece and secure in place. Attach the remaining eight pieces in the same manner, spacing each piece 8 inches from the center of the previous piece. Make sure your pieces are flush with the post edges.

4. Lay your remaining two posts in the same manner and attach your nine horizontal lattice pieces as you did with the first side.

5. Attach three vertical lattice pieces to each side section. Each vertical piece should be spaced 10 1/2 inches from another and attached vertically to the top and bottom horizontal piece with 1 1/2-inch galvanized screws.

6. Sand both side sections until smooth.

Final Assembly

1. Place the arch section face down. Place the side section up against the right arch end. Line up the side posts with the two ends of the arches and rail, with the lattice facing out.

2. Secure the right side of the arch section to the right lattice section, from the rail into the posts, with two 3-inch galvanized screws. Repeat for the left side.

3. Place two 60-inch braces horizontally from post to post. One brace should be close to the top of the posts and the second should be equal to two-thirds the length of the lattice. Attach with two 3-inch screws per brace. Flip the archway over and attach two braces to this side as well.

4. Use the post-hole digger to make four holes. Your holes should be the depth required by local codes plus about 6 inches. Space the holes 42 inches apart, front to back, and about 50 inches side to side.

5. Add 6 inches of gravel to the bottom of each hole for water drainage. Mix the concrete following the manufacturer's instructions.

6. Pick up the archway by the temporary braces and place the posts into the holes. Check for level and adjust as needed by removing or adding gravel.

7. Pour the concrete mix into the holes around the posts, filling to ground level. Use a stick to stir the concrete after pouring to eliminate air bubbles. Allow the concrete to cure 24 hours.

8. Remove the temporary braces on the archway and paint or stain as desired. Add climbing plants near the trellis sides.

Tips & Warnings

• Contact your local codes department to find out the depth required for your posts.

• When lifting the archway to place the posts in the holes, you'll need an extra person or two to help.

• Wear safety goggles to prevent eye injury.

References

• Move: Arched Arbor

Resources

• Popular Mechanics: How to Build a Garden Arbor: Simple DIY Woodworking Project