If you’ve ever wondered why one room in your house is always hotter (or colder) than the rest—or why your utility bills seem higher than they should be—you’re already thinking like an energy auditor. The good news: yes, you can do a basic DIY energy audit  and uncover plenty of common efficiency problems. The not-so-good news: a DIY audit has limits, especially when you need diagnostic testing, verified measurements, rebate paperwork, or HVAC load calculations . For homeowner