Big Building Science Ideas. Short, Practical Videos.
Welcome to Building Science Shorts, a video series created by Brynn Cooksey Sr., “The Air Doctor,” to simplify the science behind healthy, comfortable, and energy-efficient homes.
Whether you’re a homeowner, contractor, energy auditor, or HVAC professional, these short videos break down complex concepts into practical lessons you can apply right away. From air leakage and insulation to load calculations and indoor air quality, Building Science Shorts helps you understand how homes really work.
What You’ll Learn
- Air Leakage & Air Sealing – Discover how uncontrolled air movement affects comfort, efficiency, and durability.
- Insulation Fundamentals – Learn the role insulation plays in reducing heat transfer and improving performance.
- Energy Audits – See how diagnostic testing and utility data reveal opportunities for energy savings.
- HVAC System Design – Understand why proper sizing and airflow matter more than equipment brand names.
- Indoor Air Quality (IAQ) – Explore the factors that influence the health and safety of the air you breathe.
- Humidity & Comfort – Learn how moisture impacts occupants, buildings, and HVAC performance.
- Duct Diagnostics – Understand how poorly performing duct systems can affect comfort and efficiency.
- Heat Pumps & Electrification – Separate fact from fiction and learn when these technologies make sense.
Why Building Science Matters
Many comfort, health, and high utility bill issues are symptoms of a larger problem: homes function as systems. Addressing one component without understanding how it affects the others can lead to unintended consequences.
Building science helps answer important questions such as:
- Why are some rooms always too hot or too cold?
- Why are energy bills so high?
- Why does condensation form on windows?
- Why does a new HVAC system still leave the home uncomfortable?
- Why do some homes have persistent indoor air quality issues?
The answers often lie in the interaction between the building shell, mechanical systems, and the people living inside the home.
Learn in Minutes, Apply for Years
Our goal is simple: make building science accessible.
Each Building Science Short is designed to deliver practical knowledge in just a few minutes, giving you the confidence to make informed decisions about your home, your business, or your next project.
Whether you’re improving your own home or advancing your professional expertise, these videos provide insights that can lead to greater comfort, healthier indoor environments, and lower energy costs.
About Brynn Cooksey Sr.
Brynn Cooksey Sr., affectionately known as the “Air Doctor,” is the owner of Air Doctors Heating and Cooling and HVAC U. As an educator, contractor, and nationally recognized building performance expert, Brynn has trained more than 15,000 HVAC technicians, electricians, and energy professionals since 2010.
Through Building Science Shorts, Brynn shares the same practical, field-tested knowledge that he uses in classrooms, conferences, and homes across the country.
Explore the latest Building Science Shorts below and discover how understanding the science behind buildings can help create homes that are more comfortable, healthier, safer, and energy efficient.
Understanding the Building Shell
June 12, 2026
When it comes to the building shell, there are two major issues to consider: air leakage and insulation. While these problems are often related, they are not the same thing and should not be treated as if they are interchangeable.
Many older homes suffer from insufficient insulation and are also leaky, allowing conditioned air to escape and outdoor air to enter through gaps and cracks in the building enclosure. Insulation slows the transfer of heat, while air sealing controls the movement of air. Both are important, but they solve different problems.
One of the most important principles in building science is to air seal before you insulate. If you add insulation without addressing air leaks, you may miss an opportunity to improve comfort, energy efficiency, indoor air quality, and the overall performance of the home.
Understanding the difference between air leakage and insulation deficiencies is the first step toward developing effective solutions that deliver measurable results.