A footbridge is a great addition to any landscape and enhances the feeling of getting away from the world, acting as a portal to a relaxed, carefree space. This is a simple one-day project that you can complete with common tools.
Footbridge Project Details
Use the following steps to construct a 16-ft by 3-ft bridge. You may, of course, change any dimensions you wish. Just remember to scale up or down accordingly. If you decide to make the bridge wider, don't allow the stringers to be more than 24 inches on center (OC).
These instructions are intended solely for a decorative bridge which rests entirely on the ground. To cross an actual gap (ditch, pond, etc.) consult your local building authorities for specific instructions and requirements.
Lay Out and Cut the StringersStep 1
Use 16-ft 2 by 12s for the stringers. Square both ends of a 2 by12 and cut it exactly 16-ft in length.
Measure up 4-n on each end of the 2 by 12 and make a mark. Locate the center of the 2 by12, measure 1 1/2-ft (18-in) toward the left and right ends, and mark. Draw cut-lines between the marks as shown below.
Use a circular saw to cut the stringer along the cut-line. Use the first stringer as a pattern to mark and cut the other stringers.
Brace the StringersStep 1
Cut ten 14 3/4-in pieces from your 2 by 4 stock. Use the pieces of 2 by4 to brace the stringers. Install the center and intermediate braces staggered, as shown above.
Install the end braces flush with the bottom of the stringers, the intermediate braces 1-in up from the bottom of the stringers and the center braces flush with the top of the stringers.
To avoid splitting the deck boards, predrill holes for the screws.
Install the DeckingStep 1
Cut 5/4 by 6 decking boards to 36-in for decking.
Center the decking boards on the stringer frame so there's about an inch of overhang on each side. Secure the deck boards with two screws at each stringer. Leave a 1/8-in to 1/4-in gap between each decking board. It may be necessary to cut decking boards to fit where the incline flattens out on the bridge. Stain and seal the bridge.
For this bridge, we decided not to install railings. In most areas, structures under two feet high are not required to have railings, but always check with your local building inspector for requirements in your area. If your local code requires railings or if you would like to add them to your bridge, please see the railing instructions in our deck building article.