The Silent Energy Drain in Healthcare Facilities: Managing Air Infiltration for Better Performance

By Craig Scully PE, LEED AP

April 2, 2025

Imagine running a healthcare facility where the air you control so carefully is unintentionally sabotaging your energy efficiency, occupant comfort, and even patient safety. Surprised? You’re not alone.

Air infiltration—a complex yet often overlooked issue—has become a silent energy drain in many healthcare environments. But the good news? With the right strategies, you can take control.

Van Wert County Hospital – Emergency Department exterior
Van Wert County Hospital – Emergency Department exterior

What is Air Infiltration and Why Does It Matter?

Air infiltration occurs when uncontrolled air flows into or out of a building. This can include external air sneaking through cracks in the building envelope or unintended air exchanges between interior spaces, such as an office and a pharmacy.

For healthcare facilities, where maintaining strict temperature, humidity, and pressure levels is critical, air infiltration can lead to significant operational challenges. Left unresolved, this can impact sterile environments, compromise indoor air quality (IAQ), increase energy demands, and disrupt patient safety.

Types of Air Movement

There are three types of air movement:

  1. Infiltration: Uncontrolled air entering the building from outside.
  2. Exfiltration: Uncontrolled air leaking out of the building.
  3. Ventilation: Controlled air movement designed to ensure proper IAQ.

By understanding these types, facility managers can identify infiltration patterns, assess risks, and implement targeted solutions.

Why Healthcare Facilities Are Especially Vulnerable

Healthcare environments require precise control of airflow to maintain pressure differentials between spaces (e.g., operating rooms vs. waiting areas) and meet varying temperature and humidity needs. However, conditions like wind pressure, stack effect (vertical air movement due to temperature differences), mechanical system flaws, and subpar workmanship can exacerbate air leakage.

Key impacts include:

Energy inefficiency: Uncontrolled infiltration increases heating and cooling loads, leading to higher operational costs.

Indoor air quality (IAQ) hazards: Pollutants, allergens, and moisture can enter, compromising air quality.

Comfort issues: Drafts or uneven temperatures can disrupt patient recovery and staff productivity.

Structural risks: Moisture infiltration can result in condensation, mold growth, and long-term building damage.

Condensation around window frame
Condensation around window frame

Factors Influencing Infiltration Rates:

Understanding the factors that influence air infiltration is crucial for effectively managing it in healthcare facilities. Several variables contribute to the extent of uncontrolled air movement, and recognizing these factors can help pinpoint specific areas of concern within your building.

  1. Building Envelope Quality: The quality of insulation, sealing, and construction directly affects how much air can infiltrate a building. Poor sealing or construction flaws can lead to higher infiltration rates.
  2. Climatic Conditions: Wind speed, temperature, and humidity variations in the environment can all influence the rate at which air infiltrates a building. For example, strong winds can push air through cracks or weak spots in the envelope.
  3. Building Height and Shape: Taller buildings or those with irregular shapes experience more pronounced stack and wind effects, which can increase infiltration rates. These effects can result in air movement from low-pressure areas to high-pressure areas within the building.
  4. Usage Patterns: The opening of doors and windows, as well as HVAC operations, can directly affect the internal air pressures and contribute to unwanted infiltration. Frequent changes in these patterns increase the challenge of controlling infiltration.

How to Measure Air Infiltration

Now that we have a grasp on what the problem is and its contributing factors, we can’t solve it without understanding the scope. Measuring air infiltration provides valuable data to pinpoint leaks and assess a building’s envelope performance. Here are the most common methods:

1. Blower Door Tests

A fan is mounted to an external door and depressurizes the building. By measuring how much air flows back in to equalize the pressure, leakage rates can be quantified. Results are expressed as Air Changes per Hour (ACH), providing an indication of how tight the building is.

2. Infrared Thermography

Specialized cameras detect areas of heat loss, making it easier to identify air leaks and poorly insulated zones visually.

3. Tracer Gas Analysis

This involves releasing a gas into the building and measuring how quickly it disperses. It provides precise data on air exchange rates.

Blower door test
Blower door test

Steps to Mitigate and Control Air Infiltration

Once identified, controlling air infiltration requires a mix of strategic planning and advanced techniques. Here are practical strategies:

1. Sealing Air Leaks

  • Caulking and weatherstripping: Seal gaps around doors, windows, and vents to prevent drafts.
  • Spray foam insulation: Ideal for sealing hard-to-reach cracks in the building envelope.

2. Upgrading Insulation and Fenestration

  • High-quality insulation: Focus on areas like walls, roofs, and foundations to minimize heat transfer.
  • Energy-efficient windows and doors: Invest in sealed units with low-emissivity (Low-E) coatings.

3. Advanced Construction Techniques

  • Aerosol sealants: Applied as a mist, aerosol sealants can fill minuscule gaps often overlooked during traditional sealing.
  • Continuous insulation: Avoid thermal bridging by wrapping the entire exterior with uninterrupted insulation layers.
  • Double-shell construction: Use an inner and outer shell design to control pressure zones and minimize infiltration.

4. Mechanical Ventilation Systems

  • Optimize airflow with balanced ventilation systems that maintain IAQ while preventing unintentional infiltration.

5. Staff Education

  • Train field personnel and building operators to understand the complexity of modern systems. Proper installation and regular inspections are vital to ensure systems perform as intended.

Leveraging Technology for Better Air Management

Modern technology offers invaluable tools for keeping air infiltration in check:

  • Smart HVAC systems: These can monitor airflows in real-time and adjust to maintain controlled environments.
  • Energy modeling software: Tools like EnergyPlus can predict how infiltration impacts energy use, allowing for optimization in the design phase.
  • IoT sensors: These sensors continuously monitor air quality and alert teams to leaks or pressure imbalances.

Practical Tips for Building Owners: Building Envelope Punch

To ensure optimal air control and energy efficiency, building owners must take a proactive approach during construction and throughout the life of the facility. You can maintain a tight building envelope and reduce infiltration rates by conducting:

Building Envelope Punch: The punch is essential to assess and verify the integrity of the building envelope during construction. Having an envelope specialist conduct the assessment ensures that all critical areas, such as insulation, sealing, and construction materials, meet the highest standards. This step minimizes the risk of future air leaks and inefficiencies.

Envelope Commissioning: Consider envelope commissioning as part of your construction projects. It ensures that all aspects of the building envelope, from materials to installation practices, align with energy efficiency goals and prevent air infiltration issues. This is a crucial step for identifying any issues early on and addressing them before they become costly problems.

Regular Inspections: Even after construction, regular inspections of the building’s seals, doors, and windows are key to identifying and fixing air leaks. These inspections can help detect wear and tear or any areas where seals may have deteriorated over time. Ensuring that these areas remain intact will maintain the building’s energy efficiency and prevent unnecessary energy loss.

Although air infiltration may seem like an invisible challenge, addressing it brings significant benefits. By tackling this issue, you can:

  • Enhance energy efficiency and reduce operational costs.
  • Improve indoor air quality (IAQ) for better patient outcomes.
  • Boost comfort and satisfaction for both patients and staff.

Implementing the right strategies and technologies not only protects your facility but also strengthens its overall performance and sustainability. Air infiltration doesn’t have to be an ongoing energy drain. With the proper tools and approaches, you can create a more efficient, resilient, and patient-centered environment that supports long-term success.

Looking for expert insights tailored to your facility? Contact our team to learn how we can help you create healthier, more sustainable healthcare environments.

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