Every Winter I use the deep litter method in the coop. Instead of regular cleaning and replacement of straw, I lay down a thick layer of straw and leave it. I will add some straw on top periodically throughout the season. The litter begins to decompose creating a great compost to add to the garden in the Spring. The hens naturally like to scratch in the straw finding seed and by doing so they aerate it. The decomposing process also creates heat which will help keep hens warm during the colder nights. Our Winter so far has, overall, been quite mild. We did have one extreme cold snap but it was short lived. Although Winter is far from over, it sure feels like an early Spring may be upon us. I cleaned out the deep litter the other day and added it to the garden to finish decomposing. It does feel good to clean it out and replace it with fresh straw.
Here is more information on the deep litter method and its benefits.