How to Build Garden Pond Bridges
- 1). Select a style for the bridge, specifically whether the bridge will be a flat footbridge or a bridge with an arch. Measure how long, how wide and how tall the bridge will need to be.
- 2). Decide whether you want to create a bridge with or without rails. Simplify the project by making a bridge without handrails if the bridge is just going to be a short accent piece, such as over a small koi pond. Add railings for safety if the bridge will be 8 feet long or more and will be used by children, the elderly of those with physical limitations. Think about adding a middle rail for decorative purposes, and options such as rope instead of wood for the rails to give the bridge a rustic look.
- 3). Determine how many posts you will need and the height for each. Take careful measurements for the posts. Allow posts for every 4 to 6 feet in length. Factor in the extra height you will need for posts that will be underwater, versus the height for posts that will be at the ends of the pond, and for posts that will be attached to an arch for a rising bridge (if you choose that type design).
- 4). Draw a simple sketch for the bridge. Identify where the posts will need to be placed, and the railings, if you are going to have them. Include the measures on the sketch. Keep in mind that the posts for the center of the pond will be underwater and will need to be longer than the posts at the ends of the bridge. Think about additional decorative elements such as end caps or balusters to your design and indicate them on your sketch.
- 5). Take a digital photo of the site for the bridge as a reference for yourself and whoever assists you at the lumberyard or lumber department of your home improvement store.
- 6). Choose a wood that will withstand the climate where you live and can withstand being underwater. Consider different types of wood for bridge and rail versus the posts placed underwater. Get the lumberyard to cut the wood for the bridge to meet your needs and specifications, including the arch piece if you are creating a rising bridge. Be open to any advice given on adjusting wood types and materials.
- 7). Use common deck braces and brackets to install the posts under water. Paint the end of each post that will be submerged into the water with 2 to 4 inches of black bitumen paint to minimize water from seeping into the posts. Take care not to cut the pond liner during the installation of the posts.
- 8). Use wood decking screws to drill the cross bearer pieces of long wood, or the arch (if you are making a rising bridge) to the posts. Drill wood pieces on top of the posts for connecting the walking path wood pieces. Add balusters for bridges with handrails, and a middle rail (if desired).
- 9). Stain or paint the bridge in colors of your liking. Varnish the bridge or add a waterproofing sealant for extra protection. Decorate with boulders or heavy cement urns at each end, and to give the bridge extra reinforcement. Add flowers or ferns for an extra decorative element.
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