Waist width is distance form edge to edge in the thinnest place between bindings.
There are two schools of thoughts for choosing the best width snowboard for rider.
School of thoughts #1: The most suitable waist width for rider is where boot overhangs over the edge on the heel and toe from 1 to 2 cm form on each side.
School of thoughts #2: The most suitable waist width for rider is where foot length is equal to the width of snowboard at inserts or overhangs a bit.
It has to be taken in the account the fact that choosing the width snowboard, it has to be taken into account lower part (edge and running base), since this part is in contact with snow.
Both schools are right, because when rider’s foot takes a position on the snowboard from edge to edge, the boot usually overhangs on 1-2 centimeters beyond the edge on each side. Of course, in this case, the overhang of the boot largely depends on the profile of the boot.
Note: Boot with the smallest profile that exists does not exceed the size of the foot by 2 centimeters. The largest boot profile does not exceed the foot size by 4.5 centimeters.
Why waist width is important?
School of thoughts #2 recommends that foot has to have a position on the snowboard from edge to edge (or slightly more), so rider’s foot should create enough pressure on the edge performing turns.
Despite this judgment, there is gap that does not affect the force of pressure on the edge. But, if rider’s foot is too small for the snowboard, then it makes difficult to create enough pressure on the edge, which in turn contributes to very difficult turns initiation and the snowboard feels difficult to control and less responsive.
Note: Lightweight people will feel even more difficulties to control snowboard if their feet are much smaller than the width of the snowboard at bindings location. People who, on the contrary, weigh more wont feel this much, as they have the opportunity to apply more pressure.
On the other hand, too large a overhang neglects the position of the school of thoughts #2. The reason is that too large overhang creates the risk of unwanted contact of boot with snow during turns. And this, in turn, creates great discomfort riding snowboard.
Typically, 5 mm overhang on both sides (a total of 10 mm) should be maximum, but on the other hand, foot should not be less than 5 mm of snowboard width in total (i.e. 2-3 mm less on the toe and heel side).
Talking about the boot size, this suggests that boot should not overhang beyond the edge more than on 20 mm on each side (of course, this depends on the profile of the boot; the smaller the profile of the boot, the more foot can overhang beyond the edge, and boot with a large profile does not give the opportunity to overhang much).
But if foot is less than the width of the snowboard at the location of bindings, then the profile of the boot does not play any role. Still, it is not recommended to have foot smaller than the width of the snowboard at inserts by 2-3 mm on each side.
Of course, it is possible to go with 2.5 centimeters overhang on each side, but this will create difficulties entering long curves at carving.
Tip: If the non-recommended overhang is still present, then it is better to shift bindings so that the larger overhang is on the heel side, and not on the toe side. This is explained by easier entering into the curve on the toe, and the contact of the boot with snow is more likely here. For example, if total boot overhang is 4.5 cm, then it is better to leave overhang on the toe of 2 centimeters, and leave 2.5 centimeters on the heel.
Aggressive Riders/Carving
If rider likes to go into long curves (standing on the edge), then it is not superfluous to add 2-4 mm to the snowboard waist width. Extra width reduces likelihood of the boot to contact snow. Low profile boots are also recommended.
Beginners
Beginners can afford bigger overhang, since it is unlikely that carving elements are present at the beginning of learning. But if it is planned to purchase snowboard for a long period, then it is recommended to adhere to above recommendations.