Wooden gates are simple structures that usually contain a front facade, back braces, as well as metal hinges and a latch, which allow the small wooden door to open and close. Since the wooden braces are exposed to the elements, they also become a vital part of the design. Occasionally the front and back side of a gate are reversed, so the pattern formed by the bracing members becomes the front of the enclosure. In either situation, a wooden gate is usually braced with two horizontal boards and at least one diagonal piece, which ties the whole unit together.
Lay out the vertical slats of the gate on a pair of saw horses and arrange the pieces so they create the final configuration of the gate. At this point, all boards should be cut to size, shaped (if necessary) and sanded. When laying out the planks, place the better sides facedown, as they will be the front of the gate.
Cut two pieces for your horizontal bracing. Length can vary, but the most common scenario is that each board is cut to the exact width of the gate. The hinge side of the horizontal brace should be flush with the outside edge but, on many occasions, the latch side of the cross brace will be shortened by 2.5 or 5 cm (1 or 2 inches) to allow for complete closure against a post.
Set each cross piece about 7.5 cm (3 inches) from the top and bottom of the gate. Pre-drill your screw holes with a drill bit that is just slightly smaller than the shank of the screw. Arrange the screw holes so that two or three land in each vertical plank.
Attach both cross braces with galvanised builder's screws. A special screw gun is the best tool for this job, but a variable-speed drill with a screw tip can be used for small projects.
Lay an uncut board on top of the unfinished gate. This will be the diagonal brace and it should stretch between the two cross braces. Begin at the top corner above the latch and run the board to the opposite bottom corner, located near the bottom hinge. Mark the top and bottom cut with a framing square, so the diagonal piece fits tight between the two cross pieces.
Cut the diagonal piece and attach this board to the back of the gate with the galvanised screws. Do this in the same manner as was used to attach the cross bracing. At this point, you should have a functional gate with Z bracing. Continued bracing can be applied to the same gate, but its presence is optional.
Lay one board on the back side of the gate, so it stretches diagonally from the top corner to the bottom corner. When done correctly, this board should run in the opposite direction of the first diagonal piece to form an X-shaped design.
Mark the board in four places to create an outline for the second installation of diagonal bracing. This will yield two cut pieces with sharp angles on both ends.
Cut the board with a circular saw to create the final two pieces of the X pattern.
Attach the two pieces to the back of the gate by making pre-drilled holes, then inserting a galvanised screw in each hole. This completes the X design.
The length of the galvanised screws should be about 6 mm (1/4 inch) shorter than the thickness of the gate. If the same wood stock is used for both the facing and the braces, the thickness will be twice the thickness of one board. The X design is stronger than the Z design. All the bracing must be of the same thickness, but if extra strength is desired, the back braces can be thicker than the facial boards. Always put spaces between the vertical facial pieces to cut down on wind resistance. A tall gate may require an additional middle cross brace. A 5 cm by 10 cm (2 by 4 inch) frame with the frame boards turned on edge can also be used as bracing.
The tips of the galvanised screws should not penetrate the front surface of the gate. Large gates can present problems for children while opening and closing.