Permafloat - Frequently Asked Questions

Q: How many float drums will I need under my dock?

A: As a General rule of thumb, use the following figures when figuring the number of floats you will need for the docks you are building: Residential - 30 pounds per square foot; Commercial - 40 pounds per square foot.

Example: Using PERMAFLOAT Model # CP-37212 (36" W x 72" L x 12" H with 1,030 pounds of buoyancy per float drum)

Residential: 6' W x 20' L = 120 square feet x 30 pounds per square foot = 3,600 pounds of flotation needed. 3,600 pounds divided by 1,030 pounds (buoyancy of the drum) = 4 Model # CP-37212 float drums needed.

Commercial: 6" W x 20' L = 120 square feet x 40 pounds per square foot = 4,800 pounds of flotation needed. 4,800 pounds divided by 1,030 pounds (buoyancy of the drum) = 5 Model # CP-37212 float drums needed.

* Generally you will round up the number of floats needed to the nearest even number. NOTE: There are many factors that complicate the above formula. Factors such as additional loads applied to the dock, ramps, structures, tables and storage boxes may require increased support. Please contact TMP MARINE PRODUCTS to discuss your specific needs.

Q: Where should the floats be placed?

A: The Float Drums should generally be placed around the perimeter of the dock, to provide the best support and stability. Finger Docks generally require additional flotation at the end of the dock, to reduce deflection.