How to Make Floating Boat Docks

A floating lobster boat dock provides a place to unload lobster baskets.

Floating boat docks are the best choice for situations where the water depth varies widely, whereas fixed docks are better suited to shallow water. According to the Virginia Department of Game and Inland Fisheries, floating boat docks "are hard to keep in place unless pilings are provided along the sides for the pier to ride up and down." Your projected dock site should be evaluated for the best method of anchoring your floating dock. Construction materials for floating boat docks include wood, aluminum and concrete. Flotation is typically provided by either empty plastic 55-gallon barrels or flotation billets.

Things You'll Need

• Hammer
• Saw
• Drill
• Countersink bit
• Wrench
• Flotation billet
• 4-by-4 pressure-treated lumber
• 2-by-10 pressure-treated lumber
• 2-by-6 pressure-treated lumber
• 3/8-inch bolts with nuts and washers
• 3 1/2-inch galvanized nails
• Radius-edge pressure-treated decking

Instructions

1. 

   This floating boat dock has tie rails to provide boat tie up.

   Decide on materials. Floating boat docks are constructed of a variety of materials, including wood, aluminum and concrete. The flotation quality is afforded through the use of empty 55-gallon barrels or with blocks of styrene.

2. 

   Countersinking bit sizes are determined by bolt diameter and degrees of bolt head.

   Build the frame for your boat dock. Cut 16 1/4-inch lengths of 4-by-4 lumber for use in each corner. Bolt 2-by-10 lumber to the 4-by-4 posts to form a rectangular frame. The top edge of the 2-by-10 lumber should be flush with the bottom edge of the 4-by-4 post. Countersink bolt heads.

3. Lay cross ties evenly spaced on the frame. Nail the cross ties into place.

4. Attach 2-by-6 skirting. Bolt skirting boards to the 4-by-4 posts flush with the top of the posts.

5. Place flotation billets on cross ties. Use 2-by-6 lumber for skids across the billets. Bolt the skids in place.

6. 

   Bracing provides structural support for the deck of your boat dock.

   Invert your boat dock and install lengthwise and crosswise bracing inside the frame. Bracing should be no more than 16 inches apart.

7. Build additional sections if you want a longer dock. Attach sections with eye-bolts and steel rods.

Tips & Warnings

• The use of standard-length building materials reduces the cost of your boat dock.

• Countersink all bolt heads on your dock to prevent damage to your boat.

• Decking on floating docks should not overlap the outside stringers by more than 2 inches to prevent tipping when someone steps on the edge of the decking.

References

• Virginia Department of Game and Inland Fisheries: Building Boat Ramps
• Dock Builders: Plans for Build-It-Yourself: Floating Docks, Rafts and Boatwells
• Volvo Speed: Countersinking Guide
• James Dulley: Deck Building Basics
• Boat Building: How to Build a Boat Dock
• West Coast Floatation: Let's Learn About Docks and Ramps

Resources

• Read this Article in Spanish
• Yacht Sales: Dock Lines