This handsome gateway is traditional in inspiration but has clean, elegant lines suitable for any contemporary setting. The ornamental detail of the posts is simpler than it looks -- layers of dimensional lumber do the trick. However, making the arch is a carpentry task best tackled by experienced do-it-yourselfers. Set the height and width of your gateway to suit your site, but be sure the gate opening is at least 3 feet wide and the posts are at least 5 feet high for adequate headroom under the arch.
Lay out the fence line and gate location with stakes and mason's line. Determine the gate dimensions and order materials accordingly. (The materials list assumes a gate 3 feet wide, with posts 5 feet high.) Cutting the mitered edges of the cornice trim is easier with a table saw, chop saw, or radial saw. Plan to build the picket gate first. It will be used as a guide for locating the gate posts. Complete the gateway before adding the picket fence. Check with your local building department for requirements regarding setback (the distance from public sidewalks, street curbs, and neighbors' lot lines), picket spacing, and fence height. Check for the location of underground utility lines before digging the postholes. Ask that stake markers be set.
1. On a piece of cardboard, mark a radius equal to the width of the gate opening. Cut the cardboard to make a template for setting the gate pickets. (Save the template for setting the height of fence pickets on each side of the posts.) Precut enough pickets for the gate and make a spacing gauge. Lay the pickets on two sawhorses and attach 1 x 4 bracing to the outermost pickets, making sure their tops are even. Set the other pickets in place so their tops just touch the arch template. Allow the bottom ends to run long. Double-check the squareness of the gate before adding the diagonal brace. When all the pickets are fastened, snap a chalk line and trim the pickets with a handsaw or circular saw.
2. Use the gate to position the posts, allowing for 2 x 4 blocking and 1 x 8 boxing, and 1/2 inch for swing clearance. Install the posts, setting the posts taller than needed. After the posts are in place, level across their tops and trim them 4-1/2 inches lower than the final desired post height. Add 2 x 4 blocking to the posts about every 2 feet and where the fence rails or gate hinges will be attached. Use 1x8s to make the box, fastening the edges with progressively overlapping butt joints as shown at left. Trim the 1 x 8 box so that when slipped over the post, it will be 2 inches above the ground.
3. Slip the 1x8 box over the post. (Variances in humidity, warp of the boards, or finished dimensions may require you to back out screws and trim down the blocking.) Fasten the box to the 2 x 4 post blocking with 10d galvanized casing nails. Add 1 x 4 furring as shown, mitering the corners of the bottom trim pieces.
4. Cut and fasten 1 x 2s to the 1 x 4s, positioning the 1x2s 3/4 inch beneath the top of the post, leaving a 3/4-inch reveal at the bottom of the cornice. Then add 1x8 flush with the top edge of the 1 x 2 and add 1 x 4 trim 1/2 inch below it, using 6d galvanized casing nails.
5. Add 1x4 and 1x2 trim to the cornice with 6d galvanized casing nails. Construct the cap by using construction adhesive to edge-join two 14-1/2-inch pieces of 2 x 8. Trim the cap with 2 x 2 fastened with construction adhesive and 10d galvanized casing nails. Caulk the cap thoroughly. Cut two 10-inch pieces of 2 x 8 for each post, notching them with a jig saw to accept the base of the arch. Attach the cap with 3-1/2-inch galvanized deck screws, drilling pilot holes to avoid splits. Attach the arch base pieces in the same way.
6. Measure the distance between the inside of both arch base pieces. Divide the distance in half to determine the inside arch radius. Lay out the sections of the arch, making two sets of templates to cut the arch sections from 1 x 12s. For best results, trim the end of one section and place it over the untrimmed end of the next section before marking the joint.
7. Join the sections together to complete the arch, using construction adhesive and 1-1/4-inch galvanized deck screws. Predrill and countersink the screw holes. Use epoxy wood filler to fill any gaps and cover screw heads. With a belt sander and a wood rasp, smooth the edges of the arch. Position it on top of the posts in the notched base pieces. Anchor each end of the arch by drilling horizontal pilot holes through the notched bases and inserting four 3-1/2-inch galvanized deck screws, two from each side. Hinge the gate to the posts and fasten 1 x 2 stop with 1-1/4-inch screws.