Instructions on Building Small Bridges

Small bridges are rather simply constructed.

Bridges are the easiest way to cross over water or a ravine. While large suspension bridges can take years to construct, building a small bridge for your garden or pond is a much easier task. Depending on the height your bridge is spanning, you may need to include handrails. Bridges that are relatively low to the ground and don't cross over a deep body of water don't require handrails unless otherwise dictated by local building codes. Always place a bridge on level ground so that it will be stable.

Things You'll Need

• Three 5/4-inch by 6-inch treated lumber boards (12 foot length)
• Tape measure
• Pencil
• Circular saw or handsaw
• Sandpaper
• Wood preserver
• Paintbrush
• 2-inch by 10-inch treated lumber board (10 foot length)
• String
• Thumbtack
• Jigsaw
• Clamps
• 2-inch deck screws (48)
• Screwdriver

Instructions

1. Cut the three 12-foot boards into 12 equal pieces that are approximately 30-inches long. Measure the exact length of the shortest board and base your measurements on that. Sand all of the edges when finished and coat the boards with a wood preserver.

2. Cut the 10-foot board into two equal lengths, approximately 60 inches. Mark the top center of each board.

3. Tie your pencil to the end of a piece of string. Measure 50 inches along the string from the pencil and tie a thumbtack to that point.

4. Hold the pencil to the top center mark on one board and extend the string toward the bottom of the board to its full 50-inch length. Tack it in place. With someone holding firmly to the end of the string, draw an arched line on the board. Move the string 4 3/4 inches backward and draw a second arch. Repeat the process on the second 60-inch board. These lines form the outline of the supporting arches.

5. Cut out the supporting arches using a jigsaw. Clamp the board to a worktable, leaving at least half of it hanging off the end. Move slowly and keep the blade perpendicular to the board. Sand the boards when finished cutting.

6. Set the arches upright 22 inches apart. Place one of the 30-inch boards at the top center mark of the arches. Carefully measure to ensure that there's approximately a 4-inch overhang on each side of the arches. Secure the board with four 2-inch deck screws. Each screw should be placed 1 inch inward from the edge of the board.

7. Install the remaining boards. Each board should overhang the arches by 4 inches on each side and be placed as close to the next board as possible. Don't space the boards too far apart because as the wood shrinks the gap will become larger.

References

• Rona: Build a Garden Bridge