We noticed shortly after moving in that the house was very drafty. We had the windows replaced, and I did my best to seal a crooked front door. We even replaced the skylights, but nothing we did alleviated these sometimes very cold drafts.
The home inspector noted that the insulation had dropped from the floor onto the floor of the crawlspace. This was due to the use of metal rods, or "tiger's teeth," which are no longer acceptable according to Washington State building code.