There is indeed absolutely no pad on the wind if you have reported zero wind; even 1 kt of wind eats into your margins.
But, and this is perhaps what you were asking for, that 1kt of wind does not doom you to the afterlife; it merely eats into the OTHER margins that exist, for things like the assumed level of aircraft performance, or thrust, or braking effectiveness, or ... With a notionally calm wind, it is unlikely that the wind will be grossly in error from that "calm" assumption. So the chances are, unless you are having a really bad day, some other element of conservatism will be there to cover for the wind effect.