What materials do woodpecker use for making their nests and how do they make their nests?

Woodpeckers use sawdust or woodchips within their nests, as it provides them with protection. but if you place to much sawdust or too thick of ieces of woodchips in a woodpeckers house, if any nest in it, the fledgings are going to find it hard to breathe. many people belive that the drumming of a woodpecker, is to create their houses, but it is a way of communication. to incourage woodpeckers to nest, leave a woodpecker nest with woodchips about 1 inch thick. hope this helps! :) :) :)