How to Construct Arches

Select a level location to install the arch. Measure a 4-by-3-foot rectangle and mark the outline with spray paint.

Dig a 1-foot-deep hole that is 5 inches in diameter into each corner of the rectangle. Use a post-hole digger. These holes will hold the posts for the archway. Shovel a small amount of gravel into the holes to assist with water drainage.

Cut four 7-foot lengths of 3-by-3-inch lumber using a circular saw. These are the posts for the arch. Place a post upright in each hole. Pack the dirt from the holes back into the holes around the posts by stomping around the posts.

Cut two 4-foot lengths of 3-by-3-inch lumber using a circular saw. These are the supports for the arch. Place one of the supports in between the front two posts. Slide the support all the way to the top of the posts and screw in place using a power drill and 4-inch wood screws. Repeat across the back of the arch.

Draw a 4-foot wide by 3-inch thick arch on a piece of plywood using a carpenter's pencil. Cut the arch out with a jigsaw. Use this arch as a guide to make an identical second arch.

Place one of the plywood arches across the front of the front two posts. Screw in place using 2-inch wood screws. Repeat on the back of the arbor.

Cut two 3-by-6-foot pieces of wood lattice. These will be the sides of the arch.

Place one piece of the lattice across the front left post and the back left post. Screw in place using 2-inch wood screws every 6 inches around the lattice. Repeat on the right side.

Cut six 3-foot pieces of 1-by-3-inch lumber. These will be the top of the arch.

Arrange the six lengths of top pieces evenly across the tops of the two plywood arches. Screw in place using 2-inch wood screws.

Apply wood paint or stain to the archway using a paint brush. Let the paint or stain dry completely.