Welcome to Stockton Infrared Services For Malls and Shopping Centers!
Thank you for visiting our web site for Malls and Shopping Centers!
In the picture shown, we have five (5) infrared services that can help you maintain and operate your facilities in a sophisticated manner:
- Roof Moisture Surveying
- Moisture Intrusion Scanning
- Electrical and Mechanical Infrared Predictive Maintenance
- Heat Loss and Air Leakage Testing
- Block Wall Scanning
Stockton Infrared’s Roof Services
In the picture shown, the four methods to accomplish Infrared Roof Moisture Surveys:
Stockton Infrared Thermographic Services, Inc., ThermalMapIR™, AITscan™, AreaScanIR™ and United Infrared’s RoofScanIR™, have performed qualitative infrared thermographic surveys on over a billion square feet of commercial and industrial roofs since 1989.
We bring to our clients experience, state-of-the-art high-resolution infrared imagers, digital recording equipment, techniques that have been refined over many years and the attitude that we are going to obtain the best imagery possible and produce a professional report in a timely manner.
Infrared (IR) Imagery in General
Thermal infrared (IR) imagery is imagery that shows heat. It is often in the form of a grayscale picture whose shades of gray indicate the differences in temperature and emissivity of objects in the image. Typically, objects in the image that look lighter are warmer and those that look darker are cooler. Bright white objects are the warmest in the images. Black objects are the coolest.
Any object with a temperature above absolute zero (0 Kelvin or –273 degrees Celsius) emits infrared radiation. An infrared picture only shows objects which emit infrared wavelengths in the 3000-5000 or 8000-14000 nanometer range. Objects in visible light wavelengths of 400 to 700 nanometers are detected, but only because they also emit heat. An example of this would be a warm street light that can be seen in the IR imagery, not because it emits light…but heat. We record infrared imagery onto a computer hard drive and may later create digital image files. These images may then be modified in a number of ways to enhance their value to the end-user, such as creating false-color images, stitching them together and/or creating mosaic images.
Infrared Roof Imagery
The infrared thermography method of finding moisture in flat and low-sloped roofs is based on pattern recognition and predicated on the fact that wet substrates have higher mass and therefore higher specific heat capacity than dry substrates. Areas of roof moisture contamination manifest themselves as warmer (lighter-colored) areas in the IR imagery that may be nebulous in shape and sometimes mottled in appearance, although they are commonly found in linear or puddle-like shapes. The linear shapes many times follow low areas, drainage routes, roof edges and seams. Puddle-like round or oblong shapes often form around roof penetrations such as mechanical equipment, standpipes, vents and drains. The wet areas are lighter in color because the latent heat (from daylight sunshine) in the trapped water mass is greater than in the dry, functioning insulation or roof substrate. After sunset when the roof structure cools down, wet areas of roof insulation and other materials continue to radiate heat, allowing our sensitive infrared cameras to detect the sources of heat and record them for later analysis.
On-roof infrared surveys are by far the most used method of roof thermography. To perform an on-roof survey properly, a crew of two people is needed; an experienced infrared thermographer and a helper. It is also a good idea to have the building owner’s representative for access and security, if possible.
The crew needs authorization and access to all areas and levels of the roofs from either ladders or roof hatches and time to collect data under good conditions. Very dependent on logistics, how many problems are found and how long good conditions last, an on-roof crew can survey 50,000-200,000 SF of building roofs in a night.
Areas that contain subsurface moisture are verified wet and then marked with paint directly on the roof along the outer edges of the wet area. That night with flash photography or the next day, the thermographer goes back on the roofs to take visual photographs of the areas that contain subsurface moisture.
The farther one can get from the subject of any infrared imaging survey, while maintaining a high enough spatial resolution to achieve the needed image quality, the more useful the data becomes. This is true for infrared imaging of roofs as well. Elevated roof moisture surveys offer high quality spatial resolution and high usability of the infrared imagery – the best of both worlds.
The only reason for getting very close to a suspect wet area is to mark it. A common mistake made by inexperienced roof thermographers is to take close-up images of wet areas, trying to fill the frame with the anomaly.
To perform an under-roof survey, the thermographer stands under the roof looking up at the bottom of the roof using the heat from the Sun (or lack thereof) to see the difference in mass between the wet and dry substrate from the inside of the building. The thermographer must have direct line of site of the roof from underneath.
In an open gymnasium or similar building this is pretty easy, but many buildings have acoustical tile ceilings, or something else in the field of vision of the camera, so these obstacles must be removed…usually a very labor intensive operation.
This is the only method of thermography for vinyl-backed fiberglass insulated metal roofs because there is an air gap between the insulation and the metal deck, so looking at the roof from the roof above will not work. Insulated flat or low-sloped roofs also lend themselves to the under-roof method, although the outside methods are usually easier to perform.
The most efficient way to perform roof moisture surveys is the aerial survey. The same laws of physics apply to aerial, elevated and on-roof infrared…a dry roof, low winds and no rain are needed on the night of the survey. However, the “window” when the roof is radiating heat differently from wet and dry areas is longer with aerial infrared because slight nuances of temperatures over large areas are still recognizable.
A high angle of view and high resolution are needed to produce usable imagery. The cameras that are used for on-roof surveys are not of sufficient spatial resolution to obtain good imagery from flight altitudes of 500-3000 feet above the roof.
Compelling uses for the aerial infrared method:
- Very large roofs
- Inaccessible roofs
- Dangerous roofs
- Roofs where no access is granted
- Trending of roofs over time
- The most difficult roofs to analyze
Drawing in the entrained moisture in flat and low-sloped roofs on a scaled CAD drawing with surgical precision provides a significant maintenance benefit to the roof owner. This plan view imaging allows for very accurate marking of areas of suspect roof moisture contamination and an impressive presentation as precise matching infrared images, visual images and AutoCAD drawings makes the reports clear, concise and easy to understand. AutoCAD drawings are made by drawing ‘over’ the captured visual and infrared images on the screen.
A big advantage to aerial infrared is that the infrared thermographer can wait for a good night for imaging, and survey many roofs under good conditions. If the image quality is not acceptable on a particular building roof early in the night, he can return at different times during the night, in order to image the building or many buildings under very good ambient conditions.
Why Aerial Infrared
Performing infrared roof moisture surveys while standing on the roof is not the best method because imagery from an on-roof survey is not as useful as aerial imagery. The same laws of physics apply to both aerial IR and on-roof IR…A dry roof, low winds and no rain are needed on the night of the survey. However, the “window” when the roof is radiating heat differently from wet and dry areas is longer with aerial infrared because slight nuances of temperatures over large areas are recognizable. A high angle of view and high resolution are needed to produce usable imagery. We use mega-pixel infrared imaging systems to produce high-resolution thermal imagery.
Visual photographs are taken earlier in the day or the next day. Both visual and infrared images are used to do the analysis by overlaying the AutoCAD drawing of the roof ‘over’ the digitized photographs and thermographs. The drawings are created indicating areas of suspected moisture contamination. The result is a report where visual, infrared and AutoCAD components are well matched and lined-up.
Depending on the project, we use:
- Helicopters (rotor-wing)
- Airplanes (fixed-wing)
- UAVs (rotor-wing and fixed-wing)
See a Sample Mall Roof Here!
Other Mall Services
Due to movement of air – when objects become wet, a cooling effect takes place on the object’s surface. This process is known as evaporative cooling. Thermal imaging technology allows us to map moisture paths inside and outside of buildings with this completely non-invasive technique.
Energy efficiency (heat loss and air leakage) issues in buildings is becoming more important every day. Infrared imaging and air leak testing together offer a complete package to find and document areas where the building is leaking heat energy.
There is a method that is accurate, non-destructive and inexpensive for CMU (Concrete Masonry Unit) testing. Infrared testing can be performed at any time during the construction process without interrupting any other trades or affecting the progress of the rest of the building. This is the way to see the grouted cells in the entire wall section.