
A new rower wandered around the boathouse, looking at the rowing shells
He looked half stunned and he came over and asked, “What gives with these boats?”
He didn’t want to know about oars. Or slings. Or anything else. He just wanted to know about the rowing shells. They overwhelmed him.
I get it.
For a new rower (and maybe even an experienced rower) rowing shells can be a handful.
I’ve spent the last 45 years mucking around with shells and they still drive me to scratch my head. So I put together six what-gives observations that I thought might be helpful to get a clearer understanding of our crazy world of rowing equipment.
These are six places where I’ve wanted to know “What gives?” more than once.
1. What Is The Difference Between Different Classes of Rowing Shells?
There are two distinct ways rowing shells are classified.
First, there is sweep-vs-sculling. Which is better?
Is it sculling since “twice the oars, so twice the rower.” Or is it sweep since “half the oars, twice the rower”?
It’s a turf battle I won’t venture into, but I will offer this: both these versions of rowing are very similar—equipment-wise.
The second method of boat classification is the number of rowers in the boat.
Not the number of “people” in the boat, just the number of “people tugging on oars.”
When classifying boats in this manner, coxswains don’t count. Another turf battle I’ll stay clear of.
Drilling down a bit…in sculling, where one person has two oars, the most popular classifications of boats today are these:
- single sculls (1x)
- double sculls (2x)
- quadruple sculls (4x)
And in sweep rowing, where one person has one oar, the four most popular classifications of boats today are:
- pair (2-)
- four without coxswain (4-)
- four with coxswain (4+)
- eights (8+)
There are sub-classifications according to athlete weight, ability, and by gender. However, that’s classification by people.
If we just focus on classification by equipment, its scull/sweep, and number of “rowing stations” (fancy word for seats).
Three thoughts I’d like to share about boat classification:
A) Not all classifications are prioritized the same. For example, in the US, sweep rowing is the most popular version of rowing, with eights usually being the main event at regattas. In parts of Europe, sculling is typically more popular, with sweep rowing in a minority.
I’m not sure why, just the way it is.
B) There is a pecking order of boat speed by class. According to the most recent World records a comparison of boat speed would look like this, for rowers of comparable abilities:
ROWING SHELL SPEEDS
(Faster) 8+ > 4x > 4- > 4+ > 2x > 2- > 1x > 2+ (Slower)
This pecking order holds across weight, ability and gender distinctions.
C) Some hull designs can be converted between sculling and sweep. For instance, a 4- might convert to a 4x; or a 2- to a 2x. Great to know for multi-use programs.
What-gives observation: The pecking order of boat speed slightly shifts when comparing boat classes by gender. I love coaching a men’s 4+ vs a women’s 8. For same level of rowers…they are close to same speed. There can be some good battles.
2. Why Do Rowing Shells Look Like They Do?
The design of a rowing shell’s hull has stayed basically the same since the late 1800s. Around that time, the oarlock was removed from the gunwale and stuck on an outrigger.
Before then a hull was wide.

Putting the oarlock on a rigger allowed a hull to be narrower. Which meant less resistance,

less weight…more speed.
And the design of a rowing hull hasn’t changed much since then.
Oh sure. There have been plenty of “tweaks” to rowing hulls,
- space-age fiber used in construction
- more effective riggers
- even self-bailing shell
- computer aided design
And manufacturers have invested heavily in building hulls to be faster, stronger, lighter.
What-gives observation: The hull design of 2017 looks remarkably similar to the hull design of 1900. That’s pretty cool, but also a little funky.
3. What Is In The Outer Layer Of A Rowing Shell?
The outer layer (aka “skin”) is the hard outer surface of a shell.
It’s a protective covering that supports the internal structure.
At the same time it must glide smoothly throughly the water, be durable, and, of course, look sharp.
Up to the early 1970s, the outer layer was typically made from wood. Then layers of fiberglass. Then “composites” took over.
Today composite hulls are everywhere.
A composite hull has an outer layer which consists of a combination of different materials, a combination that is stronger and more durable than the sum of the parts.
One flavor of composite is called “sandwich-composite construction.”

Over the years, I’ve rowed, coached and rigged hundreds and hundreds of boats, with many varieties of outer layers. Here are a few pros and cons I’ve noticed:
Wood outer layer
- Pro: beautiful to stunning appearance
- Con: needs LOTS of tender loving care
Fiberglass outer layer
- Pro: straight forward repair
- Con: does not play well with long-term exposure to ultraviolet rays
Composite outer layer
- Pro: rigid, keeps its stiffness over years
- Con: repairs can be challenging/complex
Sandwich-composite out layer
- Pro: rigid, keeps its stiffness over years
- Con: repairs can be challenging/complex, price
The outer layer may have a coating
Depending on the make of a shell the outer layer may have “something” added on top of it. For instance:
- wooden hulls may be covered with varnish or a thin layer of fiberglass overlay
- fiberglass hulls may be covered with epoxy/resin, gel coat, or paint
- composite hulls could be wet-sanded
Regardless of the type of outer layer and possible coating your shell has, keep in mind that weight, strength, cost, and durability are all impacted by the outer layer.
A what-gives observation: the outer layer of a shell will require maintenance, just like the skin on your body.
And like how our skin gets abused (sunburn, tattoos, piercings, dried out, etc.) so does the outer layer of a shell. It’s takes maintenance to keep the out layer working well. I’ll discuss it in future posts.
4. What Are The Different Types Of Internal Structure In A Rowing Shell?
There are basically two different types of internal structure of a shell: ribbed and monocoque.
To help explain the difference imagine a plastic food bowl you’d find in a kitchen.
The bowl has a certain amount of stiffness due to the strength and rigidity of the material its made from.
And that’s the same in a rowing shell.
However, because of forces generated within a shell by the rowers. the hull needs more strength than just that found in the outer layer. So builders add an internal structure for more strength. This also gives the rowers a place to sit and work.
Ribbed internal structure
A ribbed structure has supports that stretch from gunwale-to-gunwale-to-keel (side-to-side-to-bottom). These supports are called “ribs,” because they look like ribs in a rib cage. In fact, they lie just along the inside surface of the hull, as your ribs do in your chest.
Attached to these ribs are braces. The combination of ribs-and-braces give the hull strength, while keeping weight to a minimum.

Interesting, you may also hears ribs referred to as “shoulders” or “knees.”
Monocoque internal structure
A monocoque structure (aka “ribless”) is a simpler design. Imagine if you took the lid of your plastic kitchen bowl, shrunk it about 30%, placed it into the bowl—then glued it to the sides. You’d get a very strong structure, but … you wouldn’t be able to access the lower parts of the bowl, unless you cut holes into your shrunken lid.
That, in essence, is a monocoque design.
It’s a horizontal layer of material secured in the boat, going from bow-to-stern, and gunwale-to-gunwale; with areas cut out for foot stretchers, and to allow access to the bottom of the boat.

Why you should care about the internal construction of your shell
Two thoughts about internal construction: The first, stiffness.
As I’ll discuss in an upcoming post, stiffness is a valuable element of a rowing shell. A stiff boat is easier to balance and easier to row than a “loose boat,” and hence is usually faster. Some coaches/boatmen/designers might disagree with this. To-each-their-own.
The second, personal preference.
I’ve meet numerous rowers and coaches who prefer ribbed-over-monocoque. Just as many seem to prefer monocoque-over-ribbed.
Asked why, most just shrugged their shoulders and said things like, “It’s what we row,” or “I just like it better.”
I get it, it’s human nature.
A what-gives observation: I think monocoque hulls are stiffer, yet I find ribbed hulls easier to work on. That’s just me…your mileage might vary.
4. What Is More Important In Rowing Shells: Speed or Stability?
If you’ve rowed more than three strokes you know there’s a big problem with rowing shells—they’d rather be upside down.
Sail boats, tugs, ocean liners…those boats like being upright.
Not rowing shells.
Loaded with humans, launched, and oars removed, a shell will flip quickly. (Some versions of rowing shells don’t have this affinity. You’ll see why in a moment.)
Why does a shell want to flip when almost every other boat in the world is happy floating upright?
Racing shells, filled with rowers, have a very high center of gravity (CG), while having a low center of buoyancy (CB).

And when the CG is not directly over the CB a shell develops a list (nautical term for tipping-to-one-side). Because a racing shell is so narrow this situation is hard to correct.
So, unless action is taken (i.e., oars touching the water, or the goofball in the four-seat throwing himself onto the high-side gunwale while screaming “were all going to drown”) a shell will roll right over.
In terms of hull design, this leads to the very interesting tug-of-war of speed-vs-stability.
Pulling on one side of the rope is “speed,” the rate at which a boat moves through the water. Speed likes a hull with a narrow beam (the hull’s breadth at its width point), like a “V” shape.
But such a design is often referred to as tippy.
Tugging on the other side of the rope is “stability.” In a rowing world, this is how easy the hull is to balance and then right itself from a list (getting CG to stay and move back over CB).
Stability loves a wide, flat hull, with a bigger beam. The wider the beam, such as in some adaptive hulls, the easier to prevent a list.
But wide is not a fast design.
Why should you care? Here are a few reasons:
- You need to select a hull that is best for your rowing skill. Novice may benefit from a wider beam (stable). Skilled rowers from a narrower beam (fast).
- The speed of a crew, and how balanced they are, depends on many things (i.e., power, technique, training, etc.). The design of a hull is often not considered. Probably should be.
- Hull design may well impact the price of a shell.
My what-gives observation: if you’re coaching a crew, before you yank your hair out in frustration because they are slow-but-balanced or tippy-but-fast, take a peak at the hull design
For more depth on this, check out The Physics of Rowing by Chris Pulman
5. What Are The Different Parts And Accessories For A Rowing Shell?
Place a shell “guts up” in slings, and you’ll get a good look at the parts that make it what it is. Many of those parts:
- come standard, or
- have upgrade options (material, size, range of adjustment), or
- can be upgraded by third party vendors
Here’s a brief discussion on some of the components:
A) Foot stretcher
The platform against which rowers push, foot stretchers are critical to successful rowing.
Old-time foot stretchers were clogs, where feet slide in/out.
The most common foot stretchers today are attached sneaker, with the high-tech versions morphing into pivot systems such as Shimano Rowing Systems.
All models of foot stretchers adjust from bow-to-stern, with some versions offering more precise adjustments such as :
- up/down (heel cup height)
- in-out angle (splay)
- swiveling (foot stretcher angle).
For rower safety, all foot stretchers are required to allow rowers to get clear of the boat without using their hands.
B) Seats
Ninety-nine percent of racing shells have moving seats, which roll on tracks. The wheels of those seats are typically either single-action (using ball-bearings) or double-action (using rolling axles).
Options for ergonomic seat top designs are available from some manufacturers and third party vendors.


C) Tracks
As noted above, seats move back and forth on tracks.
Today, most tracks are adjustable, easily replaceable, and come in different lengths.
D) Riggers (aka outrigger)
Attaching to the hull, the rigger is a platform for the oar. There are different rigger designs (see following section)
E) Bowball
According to USRowing’s Rules of Rowing:
Every boat shall have a supple or plastic ball, of a white or fluorescent color, firmly attached and mounted on its bow, unless equivalent provision for visibility and protection against puncture injury is included in the boat’s basic construction. The bowball shall be at least 4 centimeters in diameter.
In other words, your boat has to have a bowball.
Period.
F) Rudder
The rudder is a moveable steering mechanism, located toward the stern.
It can be activated by a coxswain, using hands. In boats with a rudder but without a coxswain (aka “blind boat”) a rower can move the rudder with his/her foot (called toe-steering).
G) Skeg (aka “fin”)
A solid unmovable piece of material extending from the bottom of the hull, a skeg assists in steering by giving the hull a point of turning. Usually located in conjunction with the rudder.

My what-gives observation on parts/accessories: They make a difference, just like on a bicycle. However, they aren’t as important as the quality of the hull itself.
6. What Are The Different Rowing Shell Rigger Designs?
There are two main types of rigger designs in shells.
Side-mount riggers (aka side-attached or traditional riggers) are attached to the side of the hull. The attachment areas are a series of bolts that protrude through the hull.
In ribbed boat, those bolts are secured to the ribs. In monocoque hulls, with side-mount riggers, the attachment bolts go through the hull’s outer layer since there are no ribs.

Wing-riggers sit on top of the boat attaching to bolts secured to parts of the gunwale which are perpendicular to the water. The name “wing rigger” came about because they resemble wings on a plane. Wing-riggers go great with monocoque construction.

There are advantages to both rigger designs. For example, a wing-rigger distributes forces very effectively to the boat’s hull. Also, a wing usually has minimal splash in rough water, since the rigger is higher off the surface of the water.
Side-mounts have an advantage over wings because they don’t interfere with hand heights toward the catch area (more than one person has cussed a blue-streak after bashing a knuckle into a wing).
Euro-riggers (short for “European traditional rigger”) are a version of riggers that started to appear on shells in, well, Europe. They have become very popular because of how easy it is to adjust the pin, and how stable the pin is once set in place. The rigger has a slot in which the oarlock pin can easily slide toward and away from the shell, making adjusting the spread/span super easy.

My what-gives observation: The design of rigger that works best for you will be the design of rigger that works best for you. There’s a lot of hubbub about which is best. Test, test, test.
So what gives with rowing shells? I’m not quite sure if I’ve shed any light.
But I know this for sure, for a sport that hasn’t changed much in the past 100 years, there’s still a lot of things that get me to scratch my head.
If you’d like to reduce some of the hassles in your rowing (and life) and get articles like this sent directly to your inbox, just click here.
Read more:
If you’d like to find answers to some questions you might have, or questions to answers you already have, try these sites:
- Choosing between single scull hull sizes– Carl Douglas et al.
- Effects of weight in rowing – Anu Dudhia
- The physics of rowing – Chris Pulman
- The system crew boat – Klaus B. Filter