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Footwear

Flotation

Also called float, surface area

What is flotation in snowshoeing?

Flotation is how well a snowshoe keeps you on top of snow instead of sinking into it. It is a function of deck surface area measured against your loaded weight, which is your body plus clothing, boots and everything in your pack.

Flotation at a glance

Set by
Deck area against loaded weight
Loaded weight
Body plus clothing, boots and pack
Typical adult sizes
22 to 30 inch decks
Also depends on
Snow density, which varies by region and season

How flotation is sized

Snowshoes are sold by deck length in inches, and that number is really a flotation rating. A longer, wider deck spreads your load across more snow, so you sink less. Every maker publishes a recommended load range for each size, and reading that range correctly is the whole of the sizing decision.

The figure the range refers to is your loaded weight, not your body weight. Winter clothing, boots, water, food and layers add up fast, and a full overnight pack can add a third again. Sizing on body weight alone quietly puts you a size short on exactly the deep days that justified buying snowshoes.

Why snow density changes the answer

Snow is not one surface. Dense, wind-packed and spring snow supports a walker far better than cold dry powder, so the same person can be well served by a short shoe in one region and undersized in another. Flotation is a relationship between the shoe, the load and the snow, not a fixed property of the shoe.

That is what modular flotation tails exist for. Some shoes take a clip-on extension at the back that adds deck length only on the trips that need it, which is a cheaper answer than owning two pairs when your conditions swing week to week.

Why more is not simply better

A long deck is heavier to lift thousands of times a day, clumsier in trees and on sidehills, and it forces a wider stance that most people feel in their hips by the afternoon. The working rule is to buy the smallest size that carries your loaded weight in the snow you actually walk in.

What this means when you're choosing

  • The maker's published load range for the specific size, not the model as a whole
  • Whether the shoe accepts clip-on flotation tails, if your snow varies a lot
  • Deck width as well as length, since both contribute surface area
  • An honest estimate of your winter pack weight, not your summer one

Flotation vs Microspikes

FlotationMicrospikes
Problem solvedSinking into snow nobody has packed downSliding on snow that is already compressed
Typical conditionsFresh snow, early mornings, off the main trackPopular winter trails, glazed and refrozen surfaces
Weight carriedRoughly 3 to 7 lb a pairRoughly 10 to 14 oz a pair
The testYou are dropping to the shin or deeper each stepYour feet skate on a hard track

Which to pick: They solve different problems and are not alternatives. Most winter hikers who go out regularly end up owning both, and choose at the trailhead based on whether they are sinking or sliding.

The common mistake

Sizing on body weight instead of loaded weight

This is the most common error in the category. Someone weighs themselves in the morning, picks the size that covers it, then loads a winter pack and finds themselves sinking anyway. Add your clothing, boots, water, food and pack before you read the maker's range, and size to that total.

Common questions

What size snowshoe do I need?

Add your body weight to your clothing, boots and full pack, then pick the smallest size whose published load range covers that total. Most adults on rolling terrain land on a 22 to 25 inch shoe, and deep dry powder or a heavy winter pack pushes that toward 30.

Do wider snowshoes float better than longer ones?

Both add surface area, so both add flotation. Length is the dial makers actually offer, and width is usually fixed per model. A wider deck also forces a wider stance, which is the part people find tiring.

What are flotation tails?

Clip-on extensions that lengthen the deck at the back, so one pair of shoes covers two sizes worth of conditions. They are sold separately and are worth it if your snow varies a lot between trips.

Where this is defined

Where this comes up

Guides on Tom's Hiking where flotation changes which product is right for you.

More in footwear

Lug depth

Lugs are the raised blocks on the sole of a boot or trail shoe, and lug depth is how tall they are, usually 3 to 6 mm. Deeper lugs bite into soft ground; shallower ones give more contact area on rock and hard trail.

Outsole

The outsole is the rubber layer on the bottom of a shoe, the part touching the ground. It carries the lug pattern and the rubber compound, which together decide grip, and it's usually the first part of a shoe to wear out visibly.

Midsole

The midsole is the foam layer between the outsole and your foot. It absorbs impact and sets how stiff or soft a shoe feels, and it's the part that quietly dies long before the tread looks worn.

EVA foam

EVA is the light, springy foam most hiking and running midsoles are made of. It cushions well and weighs little, but it compresses permanently over time, which is why shoes go flat after a few hundred miles.

Stack height

Stack height is how much material sits between your foot and the ground, measured in millimetres at the heel and forefoot. More stack means more cushioning and less ground feel; less means more feedback and a lower, more stable platform.

Heel-to-toe drop

Drop is the height difference between a shoe's heel stack and its forefoot stack, given in millimetres. Zero drop means the foot sits level; 8 to 12 mm tilts you forward slightly and shortens the load on the calf and Achilles.

Rock plate

A rock plate is a thin stiff sheet, usually TPU or a nylon composite, embedded in the forefoot of a shoe. It spreads the load from a sharp rock across the whole foot instead of letting it press into one point.

Shank

A shank is a stiffening insert running through the arch of a boot, made of steel, nylon or composite. It controls how much the boot twists and bends, which is what lets a boot support a heavy load and edge on rock.

Rand

A rand is a strip of rubber bonded around the lower edge of a boot's upper, most often at the toe. It takes the abrasion from rock and roots that would otherwise wear through fabric or leather, and it protects your toes from impact.

Gusseted tongue

A gusseted tongue is sewn to the sides of the boot with fabric panels instead of hanging free. It seals the gap along the laces so grit and water can't get in, and it stops the tongue sliding sideways as you walk.

Vibram Megagrip

Megagrip is a Vibram rubber compound formulated for grip on wet and dry rock. It's softer and stickier than standard hiking rubber, which is why it holds on slabs and greasy roots, and why it wears out faster.

Gaiters

Gaiters are fabric sleeves worn over the top of a shoe or boot to keep grit, snow and water out. Low trail gaiters cover the collar and stop scree filling your shoes; tall gaiters run to the knee and seal the leg against deep snow and wet brush.

Microspikes

Microspikes are elastomer harnesses with short chains and spikes, roughly 10 to 15 mm, that stretch over a shoe for traction on packed snow and ice. They are the middle rung between yaktrax-style coils and full crampons, and they are not mountaineering equipment.

Crampon

A crampon is a metal frame carrying 10 or more points up to 5 cm long that binds rigidly to a stiff-soled boot, so a climber can stand on hard alpine ice and steep snow. It is the tier above microspikes, and it is technical equipment that needs an ice axe and training.

Insulation weight in grams

Insulation weight is the mass in grams of one square meter of the insulating sheet inside a boot or glove. A 400g boot uses a heavier sheet than a 200g boot, so it is warmer, but it is nothing like twice as warm.

Vibram Arctic Grip

Arctic Grip is a Vibram outsole technology built for traction on wet ice. It stays pliable at temperatures where ordinary hiking rubber goes hard, which is the reason a winter sole grips where a three season one skates.

Heel lift

A heel lift is a small wire or plastic bar behind the heel of a snowshoe that flips up so your boot rests on it during a climb. It stops your calf being held at full stretch on sustained steep ground.

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