It's heartbreaking to think that buying or trying the wrong paddleboard for your first go is the number one reason many beginners think they can’t and won't ever try again to stand up on their paddleboard.
We know that buying a paddleboard is a minefield of conflicting marketing messages, wildly different price ranges and board constructions which actually can keep hundreds if not thousands of new paddlers off the water every year.
So we're going to explain a bit about board volume, dimensions, sprinkle a light zest of science on it and let you make your own mind up about what you want to do, get and at what price.
So why might your board be stopping you from standing up...
- Your board doesn’t have enough volume in it to hold your weight (it’s too small for you!).
- The board construction isn’t stiff enough to evenly displace the water under it (it’s too bendy!).
- The board isn’t inflated to the correct pressure (as much use as flat tyre on a car!) but at least you can fix this one with more pumping!
- The board can’t take the required amount of pressure to make it operate based on it’s volume (it’s cheaply made so the manufacturing factory can’t recommend a higher pressure)
- A combination of all of the above
That's the headlines but to explain buoyancy & displacement in a bit more detail....
Buoyancy and displacement are key to paddleboard performance, but DON’T PANIC we aren’t going to start a physics lesson!
We all see and experience buoyancy and displacement almost every day; when the water level rises when we get in the bath and we feel ourselves starting to float a little, or the level of tea in our mug falls when we take the teabag out. When we push an object into water we push water out of the way, and when we take it out again the water replaces the space the object (the person or teabag) left behind, that’s why the water (or tea!) level goes up or down.
When we displace water with an object, the weight of the water we displace creates that amount of buoyant force upwards. So displacing 1 kilogram (approximately a litre) of water creates an upward force of 1kg.
It is the additional buoyancy BEYOND our weight that is insufficient in boards that are too small for us and therefore we aren’t stable and can’t stand up. This is because the potential buoyancy on offer from the volume of the board isn’t really enough or effective because it doesn’t all go into the water and therefore doesn’t displace the amount of water required to generate the amount of buoyancy required to push your weight upwards.
Think about when we jump into a swimming pool, the weight of our feet hitting the water first will creates a buoyant force because we displace a couple of kilograms of water with our feet, but if we weigh 100kg, 2 kg of force upwards isn’t going to stop us from sinking so we keep going. It’s not until all our body is in the water (and our downward momentum has stopped) that we bob back up and start to feel lighter than when on land. We are floating as the buoyant force can now be felt….
So how does that work for paddleboards?
When we stand up on a paddleboard our weight pushes down and we displace water. For every kilogram of weight we push down we need to displace a kilogram of water to create the buoyancy to support that. If we weigh 100kg then we need 100kg of buoyant force pushing up BUT at this point the deck of our board and our feet would meet at the surface of the water, so we need more buoyancy pushing upwards to actually lift us and our board up out of the water.
If a paddleboard was a perfect cube we would need to multiply the height by the width and the length to calculate the volume which we measure in litres. We do the same thing in a slightly more complicated way to take into account for the curves and rounded edges of a paddleboard.
Your board needs to displace 1 litre of water for every kilo you weigh just to get you and your board to meet at the water level (i.e. the deck of your board just under water and your feet just on the surface). You then need additional litres of volume to raise you and your board to float higher in the water.
The exact number of litres you’ll need to make that work for you will be different based on; board construction, PSI, your ability, water conditions, and how much you are planning to carry, but generally the following calculations are a good guide;
To get the minimum board volume for most paddlers you need to work out your total weight when you are on the water (i.e. you + all your clothes, safety kit, water, packed lunch, dog…)
Total weight in kg x 2.2 = Volume in litres needed
…AND if you are a beginner or a bit newer to SUP then you might benefit from more volume as you find your balance so;
Total weight in kg x 2.7 = Volume in litres needed
In practical terms this would mean our woven fusion dropstitch Miramar SX-B at 233 litres would be optimal if you need 85kg (+/- 5-10kilos) and would take 105kg at max load but if you would prefer to go up to 105kg frequently the Miramar X-B at 277 litres Miramar SX-B at 233 litres would put your load into the optimal range for that board. If you are going for longer paddles and really fancy bringing a lot of gear with you, our Supramar X-T touring paddleboard will take 140kg as its optimum load and is equipped on deck to help you hold it all in place!
If that all makes sense, then how come we can’t stand up on a paddleboard that says “paddlers / riders up to 100kg” when we weigh maybe 85kg… that’s probably because you are learning on a board that ticks all of the common reasons that a board might not be right for - so irrespective of the volume of the board, it can’t hold it’s shape to make that volume useful to you.
We came across a great video which shows how people who should be able to get up on their board are held back by a 10’ x 28” x 4” board, which we hasten to add is not one of ours! We estimate the board to have a volume of approximately 150-160 litres which would mean an optimal volume for a beginner paddler around 55kg by our reckoning and we observe it is likely single layer PVC so would not deliver that buoyancy effectively via a stiff construction. In short, completely insufficient for learners – the first minute of this fun video shows that paddleboard size is very important !
The four things you need to think about when buying a paddleboard to help you stay on your feet!
- Find a board or a brand you like and stretch your budget to get the best quality – we of course would prefer it to be a LUUM board, but failing that buy from another premium UK brand*
- Calculate your weight in kilos if Stones and Pounds are normally your thing and multiply your weight 2.2 and again by 2.7 to get a volume range that you need to work within – if you can’t find any information on board volume it’s usually a sign that the brand doesn’t think it’s important, BUT if you love the look of a board, always call them to check, they may not include it as many people just buy on length width and thickness.
- Look for a woven fusion or knitted fusion construction board. Try to avoid single layer if your budget permits. It will last longer and be less susceptible to wear and tear.
- Try and get a look at as many different boards as you can get your hands on before you buy, whether that’s during a lesson, borrowing a friends or politely asking people you bump into at the beach or elsewhere if you can take a look at their board
For anything else give us a call or drop us an email, if we don’t know the answer we’ll definitely know someone who does!
Stay safe and look out for each other on the water.
*but understand that currently inflatable paddleboards may be designed in the UK but are not made in the UK, so look beyond the union jack logos for the real story