In the real world, HVAC systems don’t operate in isolation—they interact constantly with the building envelope. For HVAC contractors and home performance pros, incorporating airtightness testing into comfort consultations is essential to educating homeowners on why comfort problems occur and how to prevent and resolve them effectively.

This session provides the conceptual framework and strategies needed to help contractors understand how building airtightness impacts system performance, occupant comfort, building longevity, and energy efficiency. We’ll focus on three essential components every HVAC technician, designer, or building science pro must master to fully understand building envelope dynamics:

Leakage Amount – The Blower Door Result:

The blower door test isn’t just an energy code requirement—it’s a critical diagnostic tool. Learn how to interpret CFM50 and ACH50 values in the context of system sizing, indoor air quality, and overall comfort control.

Leakage Location – Pinpointing the Problems:

Air leaks aren’t always visible. We’ll demonstrate techniques that eliminate guesswork—combining blower doors with infrared cameras, handheld fog machines, or precision manometers to reveal the air pathways that directly affect HVAC performance.

Pressure Drivers and System Interactions – Understanding the Why:

Air movement is driven by wind, stack effect, and mechanical systems. We’ll examine the MAD AIR (Mechanical Air Distribution and Interacting Relationships) principles developed by John Tooley and Neil Moyer, showing how pressure imbalances throughout a building can become major drivers of airflow and comfort issues.

Attendees will walk away with clear strategies to integrate these concepts into their consultations and projects. This session is ideal for HVAC contractors looking to improve their understanding of air tightness fundamentals, from component-level knowledge to whole-building systems thinking.