It’s not particularly surprising, for example, to learn that an “old” portion of a house isn’t properly insulated. It can be distressing, however, to find that a 5-year-old addition is equally weak (like it was in a house I recently worked on). When the addition was being added, it may have been possible to have taken advantage of access to crawl spaces and kneewall cavities to air seal and insulate. Similarly, a roof project could provide the opportunity to properly insulate an attic and remove ineffective insulation. I will guarantee to get the project done right the first time, so you won’t be fretting over missed opportunities years down the road.