How to Make an Arch Out of Lumber

Plan your arch. Measure the space you have in order to determine the distance between the vertical arch walls. Decide on the depth of your wall. You will need to plan for eight struts to connect the face and back of the arch. The most attractive arches have flush struts toe-nailed from the top and bottom of each strut. Also decide what sort of top you want for your arch. Popular tops include a half-circle arch, which is very difficult without advanced woodworking skills; square arch; half-diamond arch and half-hexagon arch.

Measure your lumber and cut it with a circular saw. You will need four equal lengths for the vertical walls, eight equal lengths for the struts, and two of each length used to create the arch top. A stable arch requires that all pieces be accurately cut.

Construct your side walls. Using the front wall and back wall piece, your power screw driver, and your screws, connect the two with struts. Be sure to connect the struts flush with the outer wall in order to leave a flat surface for attaching lattice to the sides once the skeleton is complete. Repeat the process for the other side. To make movement and placement of the arch easier after building, attach a temporary support piece between the two walls, making sure that the arch walls are the correct distance apart from each other. For some arches, you may need to tap in more than one temporary support.

Construct the arch head. Using your power screwdriver and screws, connect the front wall piece(s) to the rear wall pieces in the same manner as the side walls, and connect the pieces to each other.

Connect the walls to the arch head. Using your power screwdriver and screws, attach one side at a time to the arch head.

Measure, cut, and attach lattice to the outer walls of your newly constructed arch skeleton.

Drill your support holes. Using your 1/2-inch drill bit and your drill, make a hole in the bottom of each arch support wall so that you have four 1/2-inch holes. Fit your rebar into each hole to make sure the hole is wide enough to accept the rebar. If it is not, manipulate the drill bit within the hole until the rebar fits snugly.

Place your arch in its new home. When placing the arch the first time, do so without the rebar. With the arch in place, mark the spots where the rebar will be placed. Put the arch aside and drive the rebar into the ground with a hammer, leaving enough post sticking up to place firmly into the drilled holes in the wall supports of the arch. Slather the extending posts with exterior wood glue and place the arch in position with each glued piece of rebar fitting snuggly into the holes drilled into the base of the arch.

Add the final touches. Remove the temporary supports and paint or stain the newly completed arch.