Look no further! This article covers all your questions about surfboard dimensions such as length, width, and thickness in detail for practical applications.
Here is a quick snapshot of how the change in dimension can affect the surfboard.
| More | Dimension | Less |
| LENGTH | ||
| Longer board | Shorter Board | |
| Paddle Faster | Less nosedive | |
| More nosedive | Easier to turn | |
| Harder to turn | ||
| WIDTH | ||
| Wider board | Narrower board | |
| Stable | Responsive | |
| Slow when on a wave | Easier to duck dive. | |
| THICKNESS | ||
| Thicker board | Thinner board | |
| Easier to paddle | Slower to paddle | |
| Difficult to turn | Difficult to catch waves | |
| Can catch the rail | ||
| More responsive. | ||
| ROCKER | ||
| More Rocker | Less Rocker | |
| Easier to turn | Increase Speed while Trimming | |
| Less Nose dive in steeper wave | Faster paddle | |
| Fits into a barrel well | ||
| Nose Shape | ||
| More Surface Area (Round Nose) | Less Surface Area (Pointy Nose) | |
| Increase stability | Easier to turn | |
| Good for a nose ride | Easier to duck-dive | |
| Easier to take off | ||
| Can Catch the side of the nose while turning |
Let’s dive deeper to understand each topic.
Length:
The length of the board affects it in three different ways:
1. A longer board paddles faster. This is partly due to increased volume, but also because, with the same volume, a longer board will travel faster when the same amount of force is applied. This principle is well-known in boat engineering.
2. A longer board is more difficult to turn due to the additional weight and materials in front of the board, making it harder to swing around.
3. It’s easier to nose dive with a longer board, especially on steep waves. The wave lifting the tail of the board brings the nose closer to the bottom of the wave, increasing the chance of a nose dive.
Width:
Increasing width increases stability but makes it more difficult to push the rail into the water to initiate the turn.
The greater width requires more force to turn the board, making wider surfboards inherently more stable compared to narrow ones.
However, increased width also creates more drag as the board moves forward. This is the same concept as when you are playing with your hands while driving: keeping the hand vertical increases the resistance due to increased surface area. The wider board has more contact area on the water, creating drag.
Wider board is also difficult to duck dive. Width, especially in the nose area is the initial resistance when a surfer pushes the board under the water to duck dive. A narrower board will make it much easier to duck dive.
Beginner tips: When purchasing a surfboard, especially a longboard, it’s much easier to carry the board if you can wrap your fingers around it. If purchasing it online, try holding onto at least 22.5 inch or 23 inches thickness in the shop, to see what it feels like first.
Thickness:
Thickness plays an important role in determining the buoyancy of the board. A thicker board provides more buoyancy and makes paddling easier due to reduced drag when the length and width are the same. The distribution of thickness is also crucial, as increased thickness in the rail can make the board more stable but reduce responsiveness in tilting.
However, if the rail is too thin, it’s easier to bog down the rail and lose the speed suddenly.
Rocker
Increasing the rocker of the surfboard leads to three things:
1. Preventing the board from nose-diving: As the surfer is about to catch a wave, the tails of the board lift up, and nose-diving can occur. If the rocker is increased, it will follow the waterline rather than piercing the bottom of the wave.
2. Fitting into a barrel: The barrel has an elliptical/almond shape, and having a curve to fit this shape will help the surfer position well. If the board is too flat, it can slide out.
3. Making turning easier: When leaning on a rail to make a turn, the rocker decides the arc of the turn. If the surfboard has a smaller arc to turn, the turn is tighter and sharper.
Having more rockers comes with a downside.
Decrease the speed of the ride: When a surfer paddles on a heavily rockered board, one can imagine the middle of the surfboard sinking more than the tail and the nose. This curved area will act as a barrier, causing significant drag. This effect is not limited to paddling; riding speed will also be reduced.
A surfboard with a flatter outline will, therefore, paddle faster and move faster on the wave. However, this increases the chances of nose-diving, sliding out during barrel rides, and makes it stiffer to execute turns.
For an in-depth discussion on volume, I have exclusively covered the topic here.