There are a great number of different aspects to surfboard design that will influence its behaviour in the water. There are the most obvious ones, such as the overall length of the board, but there are many other, sometimes more subtle, design features that will also have an impact, including:
- Volume - Greater volume provides more float and results in an easier take-off as it will catch waves more easily. However, volume is also a disadvantage when it comes to manoeuvrability and duck-diving.
- Width – Greater width improves foiling but reduces manoeuvrability.
- Nose shapes – Greater width of the nose and the shoulder improves nose-riding on longboards.
- Tail shapes – Options include pin, squash, square, round, and swallow. Notches in the rails are called wings (the distance of the wing from the tail also changes performance).
- Concave or convex base – sophisticated flow shapes and foiling.
- Channels and flutes - cut into the board to give faster water-flow off the edges of the board and wings.
- Rocker and rails – more rocker slows it down but gives more lift when taking off. Flatter is faster.
In addition to board shape, another key aspect of the surfboard design is the number, type, size and position of the fins - the fin setup. Common choices are:
- Single fin – The classic. Some would have it no other way.
- Single fin plus stabilisers - Two additional, small fins provide additional hold in the wave face and additional stability. Popular with modern longboard designs.
- Thruster – For those looking for sharp, snappy turns. Designed for riding off the tail. Typically stalls in the turn. Holding and control works well in powerful waves.
- Twin fin ('Twinny') - Shortboard fin setup made popular in the 1970s – with an optional small, central back fin? Tends to ride better from the middle of the board. Can be changed by foiling and flow shapes through the tail, or by increasing size or shape of fins. Small fins make it flow and fast. Bigger fins give more control.
- Quad fin - Extension of twin fin setup. Gives lots of drive through the turns. Glen Winton was the first to ride a quad-fin setup in the pro circuit and got high in ASP ratings back in the 1980s. Generally used for tow-in boards for the improved stability. Like twin-fins, quad-fins can be ridden further up the board.