Thermography - Infrared (IR) Thermographic Investigation


Infrared (IR) thermography is a nondestructive investigative tool used in numerous applications within buildings for preventative maintenance, energy conservation, quality control and security functions. It is also used for quality control purposes in the commissioning of architectural, structural electrical and mechanical systems in new buildings and major retrofits and evaluations of architectural, structural electrical and mechanical systems for building condition reports on existing buildings.

Infrared thermographic imaging is a powerful investigative tool that extends the perception of the human eye beyond visible wavelengths.Footnote * High resolution images developed using the infrared spectrum show where heat is concentrated by either false colour or gray tones. For example, they can show where heat is leaking out of a building or where warmer surface temperatures exist.

West Elevation, Bank of Montreal Building, Ottawa, air leakage patterns on masonry wall assemblies on ground floor.


Footnote *

Thermal, or infrared energy, is light that is not visible because its wavelength is too long to be detected by the human eye; it's the part of the electromagnetic spectrum that we perceive as heat. Unlike visible light, in the infrared world, everything with a temperature above absolute zero emits heat. Even very cold objects, like ice cubes, emit energy in the infrared spectrum. The higher the object's temperature, the greater the IR radiation emitted. Infrared allows us to see what our eyes cannot. In our everyday world, nearly everything gets hot before it fails, making infrared cameras extremely cost-effective, valuable diagnostic tools in many diverse applications.

Return to footnote referrer *


Inspections of exterior walls of buildings identify air leaks, insulation defects, voids within materials, moisture accumulation and potential mould and fungi formation leading to indoor air quality problems. Roof inspections detect roof leaks though water accumulation within insulation layers. Electrical systems inspections identify hot spots that could lead to potential system failures. Mechanical system inspections locate overheating motors and bearings that again could lead to potential component failure. Road and bridge deck inspections detect voids that result in structural deck de-lamination and breakdown.

To date, over 80 thermographic investigations have been undertaken on building envelopes and roofs in the NCA and filed in E-DRM (page available on Government of Canada network only) (Enterprise Document and Records Management) for future reference. These files are also linked to CAPS (Capital Asset Planning System) and can be retrieved through the appropriate building file.

Thermographic images must be taken and interpreted by ASNT certified consultants. See below for the relevant standards, training and certification.

How to Find Thermographic Consultants

Equipment operators are certified by the American Standards for Non Destructive Testing (ASNT) certification process through accredited training centres in North America. These centres provide both course certification as well as ASNT certification of infrared equipment operators. There are three levels of certification available for the industry and it is important to ensure that you specify the appropriate level of expertise from the consultant. Generally level 1 is sufficient to obtain credible imagery. Level 2 consultants are required for interpretation of complex imagery and quantification of imagery. Level 3 is reserved for those wishing to train in house staff and those dealing with research and development of new methodologies within the industry. These courses deal with the various American, Canadian and Internationals standard test procedures developed over the past 25 years for building envelope, electrical, roofing, mechanical and bridge deck diagnostics.

Limiting conditions for inspection activities

For electrical and mechanical systems: these systems are generally inspected under normal to full loads to assess live performance. There are no minimum environmental parameters required but work is generally carried out at room temperatures indoors. Outdoor work can be carried out night or day and although not limited to any one season, generally done under favorable mild temperatures.

For roof moisture detection, inspections are carried out generally immediately after sunset in spring, summer and fall when roofs are clear of moisture and snow cover. Roof moisture detection using thermal gradient heat loss procedure is also possible (temperature variations of 20°C or greater allow this work to be carried out 6 to 8 hours after sunset).

For building envelope assessment for air leakage and moisture detection and thermal bridging, a minimum temperature differential of 10°C is required but generally 20 to 30°C variance is recommended. Therefore this type of inspection is reserved for winter months.

Commissioning Procedures for Electrical and Mechanical Systems

When setting up an IR inspection program for an electrical distribution system, keep the following in mind:

  • Inspections should be performed at least annually
  • Inspections should be conducted with the electrical system under normal load
  • Inspections require clear line-of-sight to inspected components
  • When possible, IR inspections should be performed 4 to 6 weeks in advance of PM shutdown to allow time to order necessary parts
  • Exceptions should be re-inspected after repair to ensure that repairs were effective
  • All new / retrofitted equipment should be inspected within 24 hours of installation
  • All findings should be documented in writing in accordance with the Guideline for Infrared Inspection of Electrical and Mechanical Systems

The building HVAC system s should be operated under normal conditions or close to full load. For commercial buildings this may involve overriding the HVAC system controls.

Lastly, infrared inspections should only be performed by ASNT certified infrared thermographers who are thoroughly familiar with the system(s) being inspected. (Building science knowledge, either professional, technical or field knowledge for envelopes and roofs, electrician or electrical engineer for electrical and mechanical systems, etc.)

Electrical and mechanical systems should be inspected by accredited Level 1 ASNT thermographers and severity of faults and recommendations can be provided also by ASNT Level 1 thermographers but for more complex systems Level II thermographers should be requested to provide analysis of imagery.

Roofing assemblies should be inspected by accredited Level I ASNT thermographers and they also can provide recommendations for required cut tests to determine presence of moisture within the roof assembly.

Building enclosure assemblies should be inspected by accredited Level I ASNT thermographers and severity of faults and recommendations should be provided by Level II thermographers and professionals having training in building sciences related to design and analysis of building envelopes.

Technical Documentation

Note: Most of these documents are available and can be obtained by contacting

  • Air-tightness and pressure monitoring (Building performance evaluation series), March 1988
  • Generic methodology for thermographic diagnosis of building enclosures (A), 1982
  • Identification of Convection Heat Loss on Exterior Cavity Wall Assemblies, April 1999
  • Infrared thermographic investigation procedures for four types of generic exterior wall assemblies April 1999
  • Minimum resolvable temperature difference (MRTD) testing: equipment specification for building performance diagnostics, 1981
  • Moisture Content Inspections (Building performance evaluation series), March 1988
  • Nondestructive Testing HandbookThe WWW icon indicates a link that takes you outside the federal government's common web environment., Volume 3: Infrared and Thermal Testing, 2001.
  • Principles of material selection and component design for optimum performance of building enclosures, 1982
  • Thermal Environment Evaluation (Building performance evaluation series), March 1988
  • Thermal Patterns Created by Moisture Accumulation Within Exterior Masonry Walls
  • Thermal patterns on solid masonry and cavity walls as a result of positive and negative building pressures, February 2005.
  • Thermal Performance Patterns on Solid Masonry Exterior Walls of Historic Buildings, April 1995
  • Thermal Resistance Measurement (Building performance evaluation series), March 1988
  • Thermographic inspections of building enclosures (Building performance evaluation series), March 1988
  • Thermographic interpretation of building enclosure deficiencies in Canadian public buildings, 1980
  • Thermography - a building diagnostic tool, 1983
  • Use of infrared thermography in detection, remediation and commissioning of thermal comfort problems in office buildings (The), 2001
  • Using infrared thermography to evaluate workplace comfort complaints
  • Verification of Dynamic Buffer Zone (DBZ) Wall Assembly Performance Using Infrared Thermography, January 2002

Examples and Infrared Images, Building Envelopes

Marshall / Four Corners Building, South Elevations, Air Leakage Testing, air leakage from interior to assembly immediately behind the metal mansard roof assembly on the third floor. (As indicated by lighter colours on top of elevation).

Lester B. Pearson Building, East elevation of west tower, reflective heat patterns at corner conditions, air leakage patterns at parapets with moisture accumulations behind spandrel panels.

Federal Food Lab, Agassiz, BC. Air leakage at wall / roof joint on end wall of office section of lab.

Roof leak pattern

Roof leak at parapet

Examples and Infrared Images, Electrical Systems

Examples of Maintenance Testing Using Infrared Cameras Images:

Internal breaker connection problems are shown in these infrared images here.

Examples of Mechanical Systems

See Predictive Maintenance Using Infrared Cameras Images The WWW icon indicates a link that takes you outside the federal government's common web environment. for other examples.

Piping - IR camera assess the condition of dozens of vessels and miles of piping, all of which operate under extreme heat and pressure.

Belt Drive (before) - Note high temperatures present in the left thermogram.
First Thermogram - 8/28/97

Belt Drive (after) - Second thermogram presumably after repair or alignment.
Second Thermogram - 9/18/97

Some of the mechanical systems that can be successfully inspected by thermography are:

  • Boilers, storage and process vessels - look for weak spots in linings.
  • Exposed or underground steam, condensate and hot water lines for leaks and damaged insulation.
  • Ductwork for air exfiltrations / infiltrations.
  • Buried cold water and drainage piping systems for leaks.
  • Steam traps, control and shut-off valves for proper operation.
  • Hot water heating systems for detection and location of air blockages.
  • Electrical equipment for loose connections, overloads, unbalanced phasing and other failures.
  • Infrared radiant heating systems for proper reflectance and maintenance.
  • Uninsulated piping systems and vessels for scale and sediment accumulations.
  • New, retrofit or maintenance work on mechanical systems as a quality control inspection procedure.

List of Reports

Date:  Pre 1998

Location: National Capital Region

Project / Building - National Capital Region

  • Centre Block
  • West Block
  • East Block
  • Peace Tower
  • Langevin Building
  • Former USA Embassy
  • National Art Gallery
  • Lorne Building, 90 Elgin
  • Sir Charles Tupper Building
  • Metro "C" Building
  • Constitution Building
  • Jackson Building
  • Promenade Building
  • Environment Canada Lab's
  • Natural Sciences Museum Building, Pink Road, Gatineau
  • National Library of Canada
  • Portage Phase I, II, III, IV, Gatineau
  • Sir John Carling Building
  • Majority of buildings in Tunney's Pasture
  • RCMP College (swimming Pool, Stables)
  • Sudbury Taxation Data Centre

Location: Quebec (Montreal)

Project / Building - Quebec

  • Guy Favreau Complex
  • Post Office Building

Location: Nova Scotia

Project / Building - Nova Scotia

  • Bedford Row Building

Location: Newfoundland and Labrador

Project / Building - Newfoundland and Labrador

  • Fisheries Building
  • Sir Humphrey Gilbert Building
  • Taxation Data centre

Date : 1998

Location: National Capital Region

Project / Building - NCR 1998

  • Bank of Montreal (see photo)
  • Victoria Building
  • National Press Building
  • Promenade Building
  • Birk's Building
  • Wellington Building
  • Marshall 4 Corners

Date : 1999

Location: National Capital Region

Project / Building - NCR 1999

  • Solicitor General HQ Building
  • RCMP HQ A, B, C and D Wings

Date : 2000

Location: National Capital Region

Project / Building - NCR 2000

  • Booth Building
  • Colonel By Building (U of O)

Location: Montreal, Quebec

Project / Building - Quebec 2000

  • ICAO Building

Date : 2001

Location: National Capital Region

Project / Building - NCR 2001

  • Lester B. Pearson Building (see photo)
  • Connaught Building

Location: Montreal, Quebec

Project / Building - Quebec 2001

  • ICAO Building

Date : 2002

Location: National Capital Region

Project / Building - NCR 2002

  • East Memorial Building
  • L'Esplanade Laurier
  • Marshall 4 Corners

Location: Prince Edward Island

Project / Building - PEI 2002

  • Summerside Taxation

Date : 2003

Location: Montreal, Quebec

Project / Building - Quebec 2003

  • 715 Peel St.

Location: Agassiz, British Columbia

Project / Building - BC 2003

  • Federal Food Lab (see photo)

Location: Sault St. Marie, Ontario

Project / Building - Ontario 2003

  • Government of Canada Building


For further information, please contact

Associated Documents


  • ISO 6 781, Thermal Insulation - Qualitative detection of thermal irregularities in building envelopes - infrared method.
  • ANSI/ASHRARE 101 - 1981 - Application of infrared sensing devices to the assessment of building heat loss characteristics
  • ASTM - C - 1153 - 90 - Standard practice for location of wet insulation in roofing systems using infrared imaging
  • ASTM - C - 1060 - 90The WWW icon indicates a link that takes you outside the federal government's common web environment. - Standard Practice for thermographic inspection of insulation installations in envelope cavities for frame buildings
  • ASTM - C - 1155 - 95(2001) - Standard Practice for determining thermal resistance of building envelope components from in-situ data.
  • CGSB - 149 - GP - 2MP Manual for Thermographic Analysis of Building Enclosures.
  • ASTM E1934-99aThe WWW icon indicates a link that takes you outside the federal government's common web environment. - Standard Guide for Examining Electrical and Mechanical Equipment with Infrared Thermography