View Entire PIM

checkCheck and repair thermal envelope.

All PIM content was independently developed and reviewed to be vendor-, product-, and service provider-neutral.


Improve energy efficiency and reduce the risk of compromised indoor air quality by regularly inspecting the building thermal envelope for gaps, cracks, and faulty or missing insulation and addressing any problems found.

  • Project Talking Points

    Openings in the thermal envelope waste energy and introduce sanitation risks by:

    • Allowing heating and cooling to escape, wasting energy.
    • Allowing unfiltered air into the building.
    • Compromising pressure relationships of affected rooms.
    • Providing pathways for pests to enter the building.
    • Allowing mold and mildew growth in concealed, moist areas.
  • Triple Bottom Line Benefits

    • Cost benefits: Sealing leaks can provide significant energy savings, which result in cost savings. See case studies for specific examples.
    • Environmental benefits: Reducing energy use always has an environmental benefit  (see Benefits Calculator page).
    • Health and safetu benefits: Depending on the improvements made to the envelope, thermal comfort may be improved, enhancing patient and staff experience.
  • Commissioning Connections

    The ASHE Health Facility Commissioning Guidelines and accompanying Health Facility Commissioning Handbook are good information sources for undertaking this performance improvement measure.

    • 3.13 Facilitate Pressure Testing
      • 3.13.1 Code Requirements – Current codes required controlled pressure relationships between critical health care spaces such as operating rooms, procedure rooms, airborne infection isolation (AII) Rooms, and protective environments (PE) rooms and adjacent spaces.
      • 3.13.4 Steps for Testing the Building Envelope – Controlling building pressure is also critical to efficient and comfortable building operation. To ensure the building envelope is properly sealed, the commissioning process should include building pressure testing.  The recommended pressure testing process for the building envelope includes these steps:

    (1) Close all doors and opening to the building.

    (2) Verify that all exhaust fans are operating at the proper airflow.

    (3) Increase the air-handling unit outdoor airflow until the building pressure relationship is positive 0.01 in. w.g. The building pressure relationship should be determined using a properly installed building pressure transmitter that measures the average differential pressure at the ground-level entrances to the building.

    (4) Record the outdoor airflows, building pressure, and outdoor air temperature.

    (5) If the outdoor airflow is excessive, the contractor [during construction] should identify and seal envelop leaks.

    (6) The testing and sealing process is then repeated until the amount of outdoor airflow is acceptable.

    • 3.14 Review Record Drawings – The health facility commissioning authority (HFCxA) should review the record drawings with O&M personnel. The HFCxA should identify know discrepancies between these documents and as-installed conditions for resolution.

    Additional commissioning resources include the following:

  • Purchasing Considerations

    If you have suggestions for purchasing considerations, or suggested sample contract language for any product or contracted service, please participate in the discussion below.

  • How-To

    1. Create a team including the commissioning agent, building engineer, and building maintenance personnel. 
    2. Develop a thermal envelope inspection work plan, schedule, and documentation deliverables, assigning roles and responsibilities to appropriate team members.
    3. Visually inspect the current state of the building thermal envelope. At a minimum, document deterioration, evidence of moisture penetration, and/or evidence of pests in the following:
      • Roof assemblies
      • Vapor barriers
      • Diffusion retarders
      • Air barrier systems
      • Rain-screen layers
      • Flashing
      • Cladding and siding
      • Windows
      • Curtain-wall assemblies
      • Doors (entrance, exit, deck, and roof access doors)
      • Thermal bridges
      • Utility penetrations
    4. In locations where the thermal envelope appears to have been breached, conduct testing for air leakage using blower door and/or infrared methods.
    5. Seal cracks and leaks to prevent excessive air infiltration/exfiltration, heat gains/losses, and moisture penetration.
    6. Install insulation in strategic locations to reduce unwanted thermal gains or losses.
    7. Coordinate envelope inspections with performance improvement measure “Retrocommission HVAC controls” /pims/208 and performance improvement measure “Practice preventive maintenance of major HVAC equipment.” /pims/9
    8. Consider installing sunscreens on exterior windows or curtain walls where solar heat frequently increases the temperature of specific areas.
  • Tools

    If you have an ROI tool, calculator, or similar resources to share, please contact us or participate in the discussion below.

  • Case Studies

    St. Thomas-Elgin Hospital

    • Key Points
      • Replaced door sweeps and seals and repaired caulking as part of a comprehensive facility renewal project.
      • Envelope upgrades contributed to C$125,000 annual savings on utilities.
      • Financed using performance-based contracting.

    The Ottawa Hospital

    • Key Points
      • Inspected and resealed envelope as part of a comprehensive energy efficiency retrofit project.
      • Envelope upgrades contributed to C$2.7 million annual savings on utilities.
      • Financed using performance-based contracting.

    St. Joseph Hospital Cardiovascular Center & Surgical Services

    • Key Point
      • Commissioning existing hospital buildings improved peak energy performance.
  • Regulations, Codes and Standards, Policies

  • Cross References: LEED

    • LEED for Existing Buildings: Operations + Maintenance
      •  Energy & Atmosphere Prerequisite 1: Energy Efficiency Best Management Practices—Planning, Documentation, & Opportunity Assessment
      • Energy & Atmosphere Prerequisite 2: Minimum Energy Performance
      • Energy & Atmosphere Credit 1: Optimize Energy Efficiency Performance
      • Energy & Atmosphere Credit 2.1: Existing Building Commissioning—Investigation & Analysis
      • Energy & Atmosphere Credit 2.1: Existing Building Commissioning—Implementation
      • Energy & Atmosphere Credit 3.1: Performance Measurement—Building Automation System
      • Energy & Atmosphere Credit 5: Measurement & Verification
    • LEED for Healthcare: New Construction and Major Renovations
      •  Energy & Atmosphere Prerequisite 1: Fundamental Commissioning of Building Energy Systems
      • Energy & Atmosphere Prerequisite 2: Minimum Energy Efficiency Performance
      • Energy & Atmosphere Credit 1: Optimize Energy Efficiency Performance
      • Energy & Atmosphere Credit 3: Enhanced Commissioning
      • Energy & Atmosphere Credit 5: Measurement and Verification
  • Cross References: GGHC

    • Green Guide for Health Care Operations Section
      • Facilities Management Prerequisite 1: Energy Efficiency Best Management Practices—Planning, Documentation, & Opportunity Assessment
      • Facilities Management Prerequisite 2: Minimum Energy Efficiency Performance
      • Facilities Management Credit 1: Optimize Energy Efficiency Performance
      • Facilities Management Credit 3.1: Existing Building Commissioning—Investigation & Analysis
      • Facilities Management Credit 3.2: Existing Building Commissioning—Implementation
      • Facilities Management Credit 3.3: Existing Building Commissioning—Ongoing Commissioning
      • Facilities Management Credit 4.3: Building Operations & Maintenance: Building Systems Monitoring
  • PIM Synergies

  • Education Resources

    Energy UniversityEnergy University Courses

    The American Society for Healthcare Engineering (ASHE) has approved the courses below for continuing education credits. ASHE issues credits in quarter-hour increments, and a total of 10 contact hours equals 1 continuing education credit.

    Industrial Insulation III: Inspection and Maintenance

    Insulation systems, like all mechanical systems, require a schedule of regular inspection and maintenance. Despite the well-known fact that inspection and maintenance are the responsibility of the owner, the reality is that most insulation systems are frequently ignored. Over time, insulation systems can also become damaged due to a variety of reasons—and if not repaired or replaced—can be rendered useless. The purpose of this course is to discuss the proper process of inspection and maintenance for industrial insulation.

    ASHE has approved this course for .50 CEU (5 contact hours).

    Industrial Insulation II: Design Data Calculations

    The pipes and installations in industrial plants often carry materials that need to be kept at a certain temperature for an optimal production process. Unless the pipes and installations are properly insulated, the proper temperature may not be maintained. And while placing the actual insulation onto the mechanics—such as a pipe, tank or vessel—is fairly easy; determining what type of insulation to use and how much—is not so easy. The focus of Industrial Insulation II will be on the process of performing calculations in order to determine the requirements/impact of industrial insulation. 

    ASHE has approved this course for .50 CEU (5 contact hours).

  • More Resources

  • PIM Descriptors


    Level: Beginner

    Category List:

    • Building and Maintenance
    • Commissioning
    • Envelope

    PIM Attributes:

    • Repair or Optimize Existing Systems (fix what you have)

    Improvement Type:

    • Commission/Retro-Commission
    • Retrofit/Renovations
    • New Buildings
    • Operations and Maintenance


    • Engineering/Facilities Management
  • Interested in underwriting this PIM? Contact us to find out how!


  1. Comment, and please add information, tools, or additional resources you think should be added to the PIM.
  2. Write a case study or a PIM to contribute to the Roadmap (links are to instructions).

Home About Topics Drivers Strategies Implementation Resources Terms of Use Privacy Policy
American Hospital Association | 155 N. Wacker Drive, Suite 400 | Chicago, Illinois 60606 | (312) 422-3000
©2010-2015 by the American Hospital Association. All rights reserved.