boat dock float

Congratulations on your new dock! A dock is not only necessary for accessing your watercraft easily, but it allows you to enjoy your waterfront property fully. Whether you fish off it, swim off it, or like to bask in the sun, a floating dock will change how you embrace summer.

But deciding to add or replace a dock is just the beginning. Now that you’ve chosen your dock style (floating), you’ll need to estimate the necessary materials.

The most crucial aspect of your floating dock is the dock floats. But how many do you need for the size of dock you want to build? 

Calculating the Size of Your Dock

The smaller your dock, the fewer dock floats you will need. So before you can determine how many floats you’ll need, you need to decide the size and design of your dock.

For example, a swimming platform won’t need as much support as a u-shaped marina-style dock.

Start by estimating the square footage of your dock to calculate the number of boat dock floats needed.

If your dock is rectangular, multiply the length by the width to get the square footage. If you want a U or T-shaped dock, calculate the square footage by breaking up the dock into rectangular sections, then calculate the square footage of each area and add each section together. 

Choosing Your Deck Materials 

Another factor in the number of dock floats you’ll need is the building materials you choose. If you use wood or aluminum framing, wood or plastic decking, and omit the roof, you can estimate that you’ll need to hold thirty pounds per square foot.

On the other hand, if you use steel frames, concrete decking, and include a roof, you will need more floats, around forty pounds per square foot.  

Estimating the Number of Dock Floats You Need

Now that you have your square footage and the pounds per square foot, multiply them to see how much buoyancy you’ll need (aka how many dock floats you’ll need.)

Let’s assume you’re using all wood materials and not including a roof. You’ll need thirty pounds per square foot. Your dock is four feet wide and forty feet long, making it 160 square feet.

160 square feet X 30 pounds = 4800 pounds of flotation needed

The largest Tech Star All Purpose float we sell provides 400 flotation pounds. Now you can divide the pounds of floatation you need by the pounds of flotation your dock float provides to estimate how many dock floats you’ll need.

4800 pounds of floatation needed / 400 flotation pounds per dock float = 12 large dock floats  


All that’s left is to plug in the numbers of your specific dock, and you’re set to easily how many dock floats you need!

How Many Boat Dock Floats are Necessary? 

It comes down to your dock size and the materials you use to build it. You can quickly estimate how many dock floats you’ll need by multiplying the square footage by thirty or forty, depending on your building materials.

If you’re ready to take the next step and explore your dock float options, contact us to learn more and get a more accurate estimate. 

Tommy Docks Podcast

Listen along as Tommy Dock's Owner Owen Jones explores the meaning of living on the water. Dive deeper into conversation with industry experts on everything outdoors. Don't be a stranger, grab a beer and join us on the dock.

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