When I think of fluffy, I do not think bamboo. I think what your looking for is thuja'greengiant'.
The best possible option for such a coldzone with those height requirements would be phyllostachys rubromarginata. But this species is a runner and one would have to understand the containment options before jumping in.
If indeed, your area is quite windy and cold in the winter, I would even think most bamboo would have some sort of leaf-burn the first few years, maybe even above ground growth death.