Here are some visual cues and clues to help you determine whether the inflatable board you are considering will deliver decent performance and longevity. We’ll also take a look at inflatable standup paddle board manufacturing process.

Understanding Inflatable Paddle Board Performance

Many factors play into the performance of a paddle board. Here we will break down some key areas to consider when purchasing an inflatable standup paddle board.

Length

The length of the board is often tied to two areas, the expertise of the rider and use scenario. Typically very short boards or very long boards offer much different handling characteristics. A mid-sized board (10-11′) is great for a beginner. Shorter boards offer better maneuverability for Surfing or River paddling. Long boards are great for carrying camping or fishing gear. What longer inflatable paddle boards lack in maneuverability, they make up with in stability and capacity.

Width

Many of the cheaper inflatable SUPs are about 29” wide, as this is the width that much cheap dropstitch cloth is produced in. By today’s standards, 29” is a narrow paddleboard, and pretty wobbly. More importantly though, narrow inflatables (especially if they are longer than 10′) will always bend significantly in the middle – not a good look… (Note: another inflatable brand has just appeared on the scene, offering 28″ wide inflatables. 28″ is seriously narrow for any SUP, let alone a low-pressure inflatable. No wonder they are extremely cheap…)

Thickness

Most inflatables use 100mm or 120mm (distance between deck and underside) dropstitch. The thicker dropstitch is stiffer, but requires more air to fill the board, and the thicker rail is less manouevrable. 150mm dropstitch is popular on inflatable raceboards, and definitely gives a stiffer platform. However, it leaves the board sitting very high above the water, creating quite a lot of windage. (And again, needs correspondingly more pump-up time and effort to inflate).

Pressure

The first thing to check is what internal pressure the board is recommended to be inflated to. Some boards can only be inflated to 12psi, others can go to 30psi+. Anything with less than around 18psi of internal pressure is very much in a lower league of performance. A high recommended pressure also tells you that the manufacturers are confident that the internal structure, construction and fittings are up to the job!

Plan Shape

The cheapest-produced inflatables are those with a narrow parallel-sided planshape. They’re slow, relatively unstable and tend to sag badly in the middle. It’s very cheap to make a straight-sided inflatable board, but that’s the only advantage. Next up are those with a bit more shape, but still with very angular corners and squared-off tails, very discontinuous lines, basically. The good inflatables have proper flowing planshapes with elegant curves, just like solid boards. Any angles or corners (other than a nice point at the bow) essentially means cheap construction and lower performance.

Rocker Line

Shaping a smooth rocker profile (the curve from nose to tail, viewed from the side) into an inflatable board is a complex process, which is why many cheaper brands don’t even attempt it.

There are three techniques used to create rocker in inflatable paddle boards.

The first, and most basic, simply involves joining sections of dropstitch with a bevel, to create a change in angle, as per the graphic here. Extremely crude, and fortunately rarely seen nowadays.
The usual low-tech method now employed is simply to cut the top of the dropstitch material at a shorter length to the bottom, so that when they’re joined it creates a natural turn-up, once under pressure.
The high tech method is to laminate the outer deck layers on under pressure, pulling tension into the dropstitch the same way that athletic support tape is used to pull tension across a muscle. This is much more technically demanding, but results in a much more progressive and accurate rocker profile.

The first two techniques tend to result in boards that are very flat throughout their mid section, and then turn up in ‘turkish slipper’ fashion at the nose, and sometimes the tail too. And their performance is significantly worse than boards with a smooth progressive rocker line – particularly in stronger winds, when those high noses really get blown around.

The fact is that inflatable boards really should not have very much rocker at all when viewed on the beach, (unless specifically designed for rivers), because the addition of a rider invariably adds a bit of extra bend, even on the very best designs. So if the board is already heavily rockered before you’ve left the beach, it’s going to be a complete banana when you’re out there!

Any inflatable board with a sharply-upturned nose instantly tells you that it comes from one of the Chinese factories specializing in low-pressure inflatables.

Rail Finishing

The rail tells you a great deal about how an inflatable board is constructed. The rails take a lot of chafe and punishment, so the more reinforcement in this area, the longer the board will last.

If there’s a line of tape at the top and the bottom of the rail, this tells you that the manufacturer has simply slapped a side panel on. This is known in the industry as the ‘Woosung Rail’. It’s a quick and cheap way of doing it, but is much less suited to holding high pressures. Boards built this way need to be looked after, as if that panel gets cut or chafes through, the board will be ruined. Boards where the top layer and bottom layer have been brought together to create a nicely rounded rail, and multiple extra layers of thick taping put on as extra reinforcement, will last a whole lot longer. The more reinforcement you can see (and feel) on the rail, the better the board will be.

Dropstitch Count

It’s very easy to see the dropstitch count and pattern on a board, simply look at the underside and spot the dimples! The closer the dimples are together, the stronger the board. High density dropstitch is vastly stronger than linear orientation. Linear dropstitch boards should not be over-inflated! See the video on the home page to witness what happens to linear dropstitch when it gets overstressed…

Seams and Taping

A good indicator as to how well the the board has been constructed can usually be ascertained from looking at the seam taping. The taping on cheaper boards can be truly appalling, as per the picture here. This is really common! And it gives a pretty good idea as to what sort of workmanship will have gone on inside the board, too…
High density dropstitch

Deck Pads

If the board has deck grip covering most of the upper surface, this is often a clue that the manufacturer is hiding the skin-bubbling that tends to occur on cheaply constructed inflatable boards. Excess deckpad simply adds weight, but offers no constructional integrity. However, if you’re wanting to use the board in any sort of surf you do need a deckpad that goes right back to the tail. Boards that only have deckpad in the middle will be useless in the surf.

Incidentally, as a general buying tip, applicable to solid boards just as much as inflatables, note also that you can tell a great deal about a board range by looking at the deckpad positioning. If every single board in the range has the same configuration of deckpad, the same distance from the tail, then you know without a shadow of a doubt that this is not a serious paddleboard brand – it’s simply a ‘range’ commissioned from a Chinese factory by someone looking to cash in on the paddleboard boom, but not actually knowing anything about the sport and its requirements.

Fin Systems

a detachable fin systemSome inflatable boards come with fins glued on permanently, others have removable fin systems, such as those shown here. Removable fins obviously have their uses on boards designed for travelling, as it makes it easier to roll the board up smaller. However, a lost or broken fin will render a board useless, so in reality it’s just one more thing to go wrong. Fancy fin systems do not add any significant performance benefits, as SUP boards are naturally very directional anyway and do not travel fast enough to require high tech fins. And because the finbox on an inflatable board can only ever be mounted onto the outside (i.e. with no internal or structural support), there will always be a relatively high degree of fin movement, even if the fin itself is stiff.

Removable fins should only be seen as a selling point when considering boards of 150mm thickness, which sit so high above the water that the extra fin depth is definitely beneficial. Even then, you’re best going for a fin system using the ‘classic’ style of fitting, so that if you lose or break your fin you can walk into pretty much any surf shop anywhere in the world and get a new one. Whereas ‘proprietary’ systems designed purely for that specific brand… what are the chances of finding a stockist with spares?

Fittings

If you’re getting the board for your boat, then a good fixing point on the bow is invaluable. Fixing points for baggage and cargo are useful too, although these can cheaply be added to any board at a later date, so don’t place too much value to them. A bad board with lots of fitting points is still going to be a bad board!Whereas a good inflatable board without the fittings you need can be fixed very easily.

Paddles

Many inflatables come as standard with a cheap aluminium adjustable or three-piece paddle. These are almost invariably pretty awful. Aluminium is really not a great material for SUP paddles – it’s cold to the touch, heavy and dull in performance. And if you’re using it in salt water, unless you keep it extremely well rinsed, it’ll soon clog up with salt. A bad paddle means bad paddling – end of story. Fiberglass is significantly better. It has more natural spring and a nicer feel, and is generally lighter. (Note: be aware that carbon is not quite the be-all-and-end-all that many people believe it to be. A good fiberglass or composite (some fiberglass and some carbon) paddle will outperform a bad carbon paddle every time. Carbon is also very fragile. Many manufacturers make their carbon paddles light simply by making the ‘wall’ extremely thin – ergo, one very easy-to-snap paddle! Most (but not all) carbon paddles under $500 should be viewed with suspicion. Buy from very well established brand names only.)

How Inflatable Paddle boards Are made

If you’re looking to invest $1000+* in a new inflatable SUP, you’ll be wanting to do a little research to make sure you’re getting the right thing. And so you should! However, most inflatable brands give very little detail other than a few ‘our boards are brilliant’ phrases in their promotional material, and some exploded-construction diagram that looks impressive and shows lots of layers.

The reason most brands don’t actually tell you very much about what goes on inside their inflatables, is primarily because they don’t actually know! They leave the manufacturing to the factory, who will also be making inflatables for literally dozens of other brands, and their involvement generally goes no further than choosing the shapes, colours and fittings.

So, on this page we’ll take you through every aspect of inflatable paddleboard manufacture, and what to look out for (and avoid!). We hope you find it useful.

Understanding Inflatable SUP Manufacturing

All the inflatable SUPs from all the different manufacturers are coming from just a few factories in China and South Korea, operating to widely differing standards and techniques.

There are four main factories in China and South Korea, making inflatable paddle boards for all the big name brands plus all the ‘one board wonder’ ranges (where someone has basically just ordered a bunch of standard off-the-shelf boards, with their own logo on). Some factories are producing for over 50 different brands! Each factory tends to follow its own standard construction technique, so basically all the boards coming out of that factory look pretty similar.

As the picture above shows, inflatable board construction is actually often extremely low-tech. Panels are cut out by hand and glued by hand, on the factory floor or on basic workbenches. So there ends up being a lot of variation in shape, weight, etc, and as it’s very far from being a sterile process, there is plenty of opportunity for grit or dust to get into the seams, generating leak spots. (This is why lower quality inflatables are never a wise investment!).

The quality variation between the various factories is huge, and the leading plants are technically way ahead of the competition. Operating to higher standards and lower tolerances, they can produce boards which can be taken to much higher pressures and have much better plan shapes and rocker lines. Red Paddle Co paddle boards are built at the brand-new Infla factory in China, a state-of-the-art manufacturing plant dedicated solely to the construction of Reds and one other brand, using the most up-to-date processes and machinery.

Understanding inflatable board dropstitch

This is what is inside every inflatable paddle board, and stops it turning into a ‘sausage’ when the board is inflated.

The inflatable paddle boards by Naish, Mistral, C4, Red Paddle Co, Starboard, RRD, Fanatic, Hobie and all the other brands all have a core of dropstitch. Many different grades are in use though Dropstitch is at the heart of all inflatable boards. It’s basically a manufacturing process that creates two layers of cloth ‘tied together’ by a multitude of very thin threads. So thin that when the board is deflated, the two layers can collapse together almost completely flat, allowing the board to be rolled up and put away. Most dropstitch is made in Korea and it is a very slow manufacturing process – dropstitch machines churn it out at just a few centimetres per minute. Hence it’s quite an expensive material to use.

Dropstitch material is now produced in a range of different thickness (i.e. the distance between the top and bottom sheet, determined by the length of the threads), stitch densities (i.e. how many threads there are per square centimetre), and patterns (whether the stitches run in parallel lines; “linear dropstitch”, or whether they are in diagonal orientation.)

Obviously, a greater density of threads using a non-linear pattern will create a much stronger construction. Linear dropstitch is much cheaper to manufacture, but it’s easy to tear and creates natural ‘fault lines’ running along the board.

The most common thicknesses of dropstitch are 100mm and 150mm. The thicker grades gives more rigidity, if the board can be pumped up to sufficient pressure. More on this in ‘understanding thickness’, and ‘understanding stiffness’

In 2012, Red Paddle Co developed 120mm dropstitch, and is still one of only a couple of brands using this size, despite it being one of the best all-round thicknesses for inflatable SUP boards.

About Paddle Board Rails

How the sides of an inflatable paddle board are created tells a great deal about how it will perform.

The dropstitch core of an inflatable provides the top and bottom of the board. The tricky bit is how to finish the sides (the ‘rails’, in board terminology. There are three different techniques in use in inflatable boards to create the rails:

The Woosung Rail: a side panel is taped on. These boards are easily identifiable by the line of tape along the top and bottom of the rail. Many of the big brands (JP, Naish, pre-2015 Starboards etc) are built this way. It’s by far the weakest way to build a rail – the sides of these boards are usually literally just one layer of PVC!
The Leewards Rail: Similar to the Woosung rail but with another layer added over the top, to create the effect of one large rail panel. You’ll find this on brands such as Mistral, Bic, etc. Better than the Woosung rail, but always still means two seams on each side of the board, and often still means that the rail is just one or two layers thick.
The Infla Rail: The top layer and bottom layers are brought together to meet, and then taped. Another outer laminate is then applied to repeat entire process. So the rail is essentially 4 layers thick. By far the most efficient and strong rail technique.

The fundamental difference between the Woosung/Leewards approach, and the Infla method, is that with the Infla method there is no way for the air to escape, whereas the other two methods, where the rail is a separate piece of material, means leakage is far more likely, and the boards can only take a certain internal pressure before they just come apart. It’s a far more complex and labour-intensive way of building a rail, but the end result is massively stronger, and much much less likely to ever spring a leak over time. Whereas the Leewards/Woosung method has those two seams all the way around the board, top and bottom, and the more air you put into the board, the more those seams are straining to open.

Paddle board thickness

The thickness of an inflatable board plays a huge part in determining its stability and performance. Too much thickness is bad news!

Making a board thicker will automatically make it stiffer but it will also affect the performance of the board. If a board is too thick it’s maneuverability and stability in the surf and on moving water will be compromised. It also has a great deal more windage (particularly if the nose rocker is over-generous, as on the cheap ‘turkish slipper’ inflatable boards). Red Paddle Co’s approach to inflatable board design is unique in that they first ensure that the plan shape and thickness is right for the board’s role, and then sort out getting it to the required stiffness. To this end, they have worked with dropstitch manufacturers to produce their own specific thicknesses of dropstitch for their boards.

100mm thickness is perfect for boards with a surf orientation. The thinner rails make for better control on the wave face and while paddling out. 100mm boards don’t offer the best stiffness though so that is why we developed our Patent Pending RSS system. We are now able to offer the stiffest boards 100mm boards with the best performance that have ever been produced. No other inflatable board performs as well in the surf as a 100mm Red board with the RSS system. Used on 9’2”, 9’4″, 9’6” and 10’ models. Learn more about the RSS System HERE.

120mm thickness is the perfect combination of stiffness and control for all round shapes. Combined with our inflatable specific nose and tail designs we have been able to produce the stiffest boards for this size. 120mm allows the rider to keep a low center of gravity, while still giving exceptional stiffness. Used on our 10’6”, 10’8” and 11’0 models (with the addition of RSS on the 11, as this board is longer and thinner than the others so needs extra rigidity.)

150mm thickness is perfect for non surfing shapes where directional stability is paramount. It gives great stiffness and means the Explorer board has enough volume to carry a lot of equipment or in the case of the 12’6” Red Race and Elite Race boards it makes the board float high to reduce drag in racing conditions. Adding the RSS system to the Race board and you have the stiffest board of this size that anyone has ever produced.

150mm is not appropriate for general recreational designs though, as it creates a lot more windage, means a whole lot more pumping-up, and much reduced all-round performance. The big test is simply to look at what happens in solid boards. You’d never see an all-round recreational solid board that’s 6″ thick, so why would you want an inflatable like that?

Paddle Board Rocker

There are several different methods utilized to put a rocker curve into an inflatable board. Unfortunately, most have a very detrimental effect on the board’s performance.

Shaping a smooth rocker profile (the curve from nose to tail, viewed from the side) into an inflatable board is a complex process, which is why many cheaper brands don’t even attempt it.

There are three techniques used to create rocker in inflatables.

The first, and most basic, simply involves joining sections of dropstitch with awful!a bevel, to create a change in angle, as per the graphic here. Extremely crude, and fortunately rarely seen nowadays.

The usual low-tech method now employed is simply to cut the top of the dropstitch material at a shorter length to the bottom, so that when they’re joined it creates a natural turn-up, once under pressure.

The high tech method, as used by Red Paddle Co and only one other brand (to our knowledge) uses a Progressive Pressure Laminating Process. The board is laid on a specially built surface. As the top layer is laminated on to the board they push high pressure rollers over the board which fixes the rocker. The board is then left to set, allowing them to create a progressive rocker profile that is ideally matched to the boards shape and the inflatable construction. Further layers of laminate tape are then applied to lock that rocker line in to position. This is a much more technically demanding, but results in a much more progressive and accurate rocker profile, designed specifically to be right for the requirements of that particular model, and to give an authentic paddle boarding experience.

The high nose on the board in the top picture, along with the high tail and the sag in the middle, all significantly inhibit performance. The problem with a board built like this is that the weight of the rider in the middle naturally just increases the rocker curve even more. The problem is further exacerbated by the very straight-sided plan shape.

Whereas the boards in the bottom picture are flat to the water, with a nice subtle upturn to the nose, just the same as you’d get on a solid board.

Any inflatable board with a sharply-upturned nose instantly tells you that it comes from one of the Chinese factories specializing in low-pressure inflatables.

Understanding paddle board weight

Why light weight inflatable paddle boards are a huge conceptual mistake.

With solid boards, a lighter board is generally a better performer, quicker to accelerate and more responsive underfoot. The weight saving has (hopefully!) been achieved by using carbon or better grades of epoxy or glass, which usually means that the board is more expensive. So, people are indeed conditioned to think that lighter is better when it comes to boards – and that you pay more for lighter weight.

However, when it comes to inflatables, weight cannot be viewed in the same way. Because there is only one way to make an inflatable board lighter, and that is to have a thinner skin, or less dropstitch threads. End of story. So a lighter inflatable board will always be less tough and more prone to damage, or less stiff.

When it comes to PVC you cannot get lighter-but-better material, it doesn’t exist. And using dropstitch with a lower thread count clearly, unambiguously, results in a lower quality board. As for the performance gains from the weight saving, these are largely cancelled out by the corresponding loss of rigidity. There is actually much more performance to be gained from increasing stiffness, than there is in shedding weight! If your board is light but floppy, you lose far more power from your stroke than any gains from being on a lighter board. And increasing stiffness is very much dependent on the robustness and structural integrity of the board.

So in general, unless the design and internal construction is spectacularly good, a lighter board usually often considerably less stiff. End result – less performance! So the message is, don’t expect longevity or robustness from a lightweight inflatable. The only way weight can be saved is by reducing quantity and quality of material.
Understanding board longevity

Why some inflatable paddle boards last so much longer than others.

Inflatable paddle board longevity comes from three things:

Construction techniques and philosophy
materials used
reinforcement (or lack of)

Let’s look at these in more detail.

As explained in ‘understanding inflatable board manufacturing’ further up this page, most inflatable paddleboards are built in an extremely low-tech fashion. Over the years that Red Paddle Co have been building inflatable boards, they have studied and dissected the manufacturing process in infinite detail, looking at every aspect and working out how it can be done better and more accurately.

Because this is what makes the difference. Any dirt that gets into the manufacturing will reduce the quality of glue seals, and create weak points in laminates. Temperature variations affect glue quality. Tiny variations in panel size can cause the finished board to have twist or an incorrect rocker line.

Red Paddle Co. call their production process Tec Air. But it’s not a specific thing, it’s the philosophy. A great deal of time and money has been invested in ensuring that the quality control processes can ensure that every board gets the same attention to detail and high standards, and staff members from the UK head office are on hand at all time to monitor the production process. They are the only inflatable brand to do this, and the end results speak for themselves.

In their words: Tec Air is not a product, it’s a process. By focusing in on the key areas of the production process we have been able to identify ways we can improve the end result. Whether it be detailing exactly where and how the layers are bonded or how the rocker curve is applied to the board, no area of the design process is ignored.

The key areas of construction are inside the board. Our attention to detail on the inside ensures the best experience on the outside.

And that’s the most important point. It’s what happens on the inside that matters, and unfortunately you don’t get to see that.

But Tec Air alone doesn’t guarantee longevity. Along with this construction philosophy, the brand only uses the very best materials (all specifically picked, and many designed exclusively for the brand), and has also devoted countless hours to identifying the weak points and ensuring that there is sufficient reinforcement where needed. On the rails for example, which are generally the weakest point on an inflatable board. It’s where all layers meet and it’s where air pressure loading is at its highest. Red Paddle Co boards have 4 layers of taping on the rails making them the strongest boards available. Most other boards are just 1 layer thick. Our 4 layer rail almost completely removes the risk of puncture or material failure, allowing you to use the board with total confidence. You could completely remove the outer rail tapes and the board would be usable. Other boards would deflate immediately if you removed or made a rip in the rail tapes.

In conclusion then – an inflatable board that is built using the best possible materials, the most accurate and efficient construction and all the right reinforcement in the right place, will last a very long time.

Understanding inflatable paddle board stiffness

There are three main ways to achieve stiffness (the most important determinant of an inflatable paddle board’s performance) in an inflatable.

The stiffer the paddle board, the better the performance. There are four ways to create stiffness in an inflatable paddle board:

Air pressure: The more air inside, the more rigid the board will be. In practice the gains becoming increasingly small once you get much above 25psi. But the difference between a board at 10psi and one at 20psi is dramatic. Don’t buy an inflatable paddle board that can’t be pumped to at least 20psi!

Thickness: A 120mm thick board is almost 40% stiffer than a 100mm board of the same shape. However, a thicker board needs more air to fill it (ie more pumping!), and sits higher on the water and is less ideal for surfing or indeed any sort of maneuvering.

Width: The wider the board, the stiffer it is. However, a wider board creates a lot more drag and is harder to paddle with proper technique, so the width still needs to be right for the board’s intended use.

Stiffness Aids: Add-on stiffening systems. While several brands have attempted to address this concept, the Red Paddle Co RSS is the only one that adds stiffness where it is needed, namely along the rails. For more on RSS click here.

Hopefully you’re now feeling a lot better informed about how inflatable paddle boards are made, and what to look out for. If you have any further questions about inflatable paddle board construction please don’t hesitate to contact us.