Free Shipping On All Orders Over $50 - 805.874.2335 - Share The Stoke

Surfboard Hull Design

I have been wondering about this a lot in Mini Simmons Surfboard design (surfboard design in general)—what is a hull and how does it influence the board and the ride?

Keep reading and I'll tell you.

Two factors are at work when a planing surfboard is in motion:

  1. the propulsion power, or force, that creates forward motion (the wave dude) and,
  2. the resistance that opposes it.

When at rest, a surfers weight is borne entirely by the buoyant force.

At low speeds, every hull acts as a displacement hull, meaning that the buoyant force is mainly responsible for supporting the surfer. As speed increases, hydrodynamic lift increases as well.

In contrast, the buoyant force decreases as the hull lifts out of the water decreasing the displaced volume.

This is the reason that surfboards with lots of rocker need more speed.

Surfboard Hull Design 

The major difference between a planing surfboard hull and a displacement hull is the way in which the surfboard travels through the water.

A displacement hull has a belly, or convex, bottom contour or planing surface. This design does not ride high on the water like a planing hull, instead plowing through and parting the water.

At high speeds a displacement hull’s tail will sink down lower and lower as a result of the “hole” created in the water as the surfboard moves forward.

A planing hull, on the other hand, will have a flat or concave bottom contour and plane up on top of the water.

The board will almost skim across the water’s surface.

Displacement Hulls

Displacement hulls push through the water as they have no hydrodynamic lift, or the surfboard does not rise out of the water as speed increases.

 Surfboard Hull Design

Planing Hull

Planing hulls are designed to run on top of the water at high speeds. To achieve this they typically are very flat at the tail. The hull design (shape) does not limit the maximum attainable speed but does affect the power required for it to get on plane (on top of the water).


Semi-displacement / Semi-planing Hulls

Semi-displacement or semi-planing hulls have features of both planing and displacement hulls. They have a maximum hull design speed. Exceeding this speed can result in erratic handling and unstable operation. There is not one hull design characteristic that differentiates semi-displacement from semi-planing hull. The greater the hydrodynamic lift and higher the hull design speed the more likely it will be referred to as a semi-planing hull.




I came across this blog post by Steven Mast of Mast Surfboards and it is an excellent discussion of the topic. "Although the recent fascination with hulls has centered around the Greg Liddle “ modified transitional displacement hulls”, any surfboard can be considered a hull.

There are displacement hulls, planing hulls and as usually is the case, some variant of the two. As soon as you put an edge at the tail of your board you have created a planing hull. The very nature of the release provided by that edge, by definition puts that board into planing mode. It the edge were left soft and round, you still have a displacement hull. Now whether it is a good one of either type is another matter.

Have you ever seen the old footage of guys towing behind motor boats on their logs?

As soon as they get going, the tail end of the board starts submarining and they can literally walk to the nose and go. This demonstrates a the principle of displacement hull theory.

A displacement hull has a theoretical hull speed, above which the water actually sucks the hull deeper into the water (I’m simplifying here). Take a sailboat or any other displacement hull and tow it. At anything above the theoretical hull speed, the boat begins to submarine, actually being pulled deeper into the water.

Old, soft edged boards are the same, as are any true displacement hulls being produced today. As soon as you put an edge at the tail, you release the water and the board begins to plane. The modern surfboard, most “hulls” included, balance these principles to achieve the desired effect or feel.

Now I’m sure I’ll get some flak for this, but displacement hulls, by their very nature, are not as fast as planing hulls (editors note: . They may “feel” faster in a section, but without the release, they are constantly dragging more than a sharp edged board would.

Now this is not a bad thing. The feeling of a well balance hull is one of the great pleasures of surfing that most people fail to credit. Surfing one well takes a different approach, especially if you are stepping off a thruster.

Single fin riders tend to have an easier time. Another thing I’ll take flak for, and I’m saying it anyway, Greg Liddle did not invent the displacement hull surfboard. He refined it to an amazing degree, made it work in a short package, championing it when it was completely against the trends of the time, but have you ever seen a Weber Foil?

Have you ever really looked at almost any board before the mid sixties? All displacement hulls, although arguably not “modified transitional displacement hulls”, whatever that means.

Please don’t take this as me dissing Greg Liddle. On the contrary, I think his boards are brilliant and have been a huge design influence for me. It’s just I get a little frustrated when I here people talk about hull this and hull that, without any understanding of what a hull is."

Some more links about hull design: > Swaylocks Surfers Forum > Surf Science > Shaping Surfboards

Wave Tribe Social Proof
Size Chart

Surfboard Leashes

You Break It We Replace It in First Year. 

Buy a leash closest to your board size—i.e. for 6'4 surfboard you need a 6' leash. 

All leashes are 7mm thick, competition leashes which are lighter/thinner 5.5 mm. 

Pioneer Day Boardbags - Fits One Surfboard

All boardbags have +2 inches. Thus a 6'6 board fit's perfectly in a 6'6 boardbag. All Pioneer bags have expandable fin gussets, so you can keep your fins on your board in the bag—or you can roll with glass-on fins.

Pioneer Sizes:

All bags have interior pockets (fins, leash and wax), bags fit industry standards. 

Our 8'6, 9'6 and 10' bags have fin slots and round noses. 

Pioneer bags also have an exterior pocket and zip all the way to the nose.

Travel Bags - Fits Two Surfboards

All Global boardbags have +2 inches, so if you buy a 6'2 boardbag, the real length is 6'4—thus you have a bit of room to play. 

Global Travel Bag Sizes:

Travel boardbags are 6'-8' inches deep to accommodate two boards—though you can travel with one in these bags without a problem—there are two interior pockets for leash, wax, and fins.

Surfboard Travel Bag Pockets Fin Wax Leash

Travel boardbags have two padded boards separators and two pockets for your gear. 

* Travel boardbags also have 13mm + 13mm of extra padding in the nose and tail.

Travel Bags with Wheels - Fits Two Surfboards

New in 2016 is the double travel bag with wheels. Sometimes you want a smaller bag with wheels, now you can have it. All Global boardbags have +2 inches, so if you buy a 6'2 boardbag, the real length is 6'4—thus you have a bit of room to play. 

Global Travel Bag Sizes:

Travel boardbags are 6'-8' inches deep to accommodate two boards—though you can travel with one in these bags without a problem—there are two interior pockets for leash, wax, and fins.

Wave Tribe Wheelie Surfboard Travel Bags

Travel boardbags have two padded boards separators and two pockets for your gear. 

* Travel boardbags also have 13mm + 13mm of extra padding in the nose and tail.

Boardbag Material & Hardware - All Bags

Side A of the bag is made from a strong density Rugged Eco Hemp exterior which is one tough fiber and naturally built to last with high impact padding protection with Rebound Foam Dynamics including open-to-nose technology.

Side B is the reflective (rental-car-roof-side) made from Reflective Energy Shield for "Cooler Surfboard Safeguard" protecting your surfboard from the sun's harmful rays made from an alloy-steel mesh weave.

All Sides are guarded by our Japanese Never-Rust-or-Break Nickel Platted Zippers streamline zipper trails and our trademarked Easy Flow Zip System.