Infrared Moisture Scan Program

Transcription

1 Infrared Moisture Scan Program Prepared for: Austin Independent School District Murchison Middle School Austin, TX Prepared by: Jim Whitten, Senior Consultant JIM WHITTEN ROOF CONSULTANTS Ted Miears, Thermographer Anderson High School 8403 Mesa Drive June 8, 2004

2 Description of Moisture Scan Survey This survey was performed in connection with The 2002 Bond Project, Phase Two Roof Improvements, and pursuant to a Roof Assessment by Jim Whitten Roof Consultants dated February 12, The purpose of the campus wide roof moisture scan was to identify and verify any wet or nonfunctional insulation, to be removed, prior to performing any roof improvements. The Infrared Survey was performed on Tuesday evening, June 1, 2004 between the hours of 8:30 pm to 12:30 AM. The Survey was performed by Mr. Jim Whitten, Senior Roof Consultant and Mr. Ted Miears, Level I Thermographer of JIM WHITTEN ROOF CONSUTANTS. The Infrared Camera used for the Survey is an Infrared Solutions FlexCam T. Infrared Thermography basically identifies thermal anomalies located on the roof. These thermal anomalies are often associated with the roof substrate materials that have retained moisture. During warm weather wet substrate materials will retain a greater amount of heat compared to adjacent dry materials. After the heat source is removed (following sunset) and the surface of the roof begins to cool, the infrared camera can detect the differential heated wet substrate materials. The thermal camera shows the wet areas as a lighter color than the surrounding dry areas. A Tramex Leak Seeker (Photo A), an Electronic Moisture Detector Instrument was utilized to further verify moisture in the roof assembly. The instrument generates two low frequency electronic signals, transmitted through parallel electrodes incorporated in the rubber electrode mat, which is attached to the underside of the instrument. Placing the unit on the roof surface in areas suspected to contain subsurface moisture readily verifies or refutes the indication of the infrared camera image. A Relative Scale from 0 (Dry) to 100 (Wet) provides an Analog reading of detected moisture. The wet areas are marked with bright colored spray paint, numbered, and documented by capturing an image in the infrared camera and a control image with a digital camera. Typically, further verification of wet areas is confirmed by taking a roof core sample to observe the condition, composition, and quantity of moisture. While the sample is open, readings are taken by a Tramex Professional Moisture Meter (Photo B). This instrument works on the principle of DC resistance. When the electrode pins are inserted into the substrate (roof insulation), the electrical resistance between the electrodes is measured and indicated on the digital display. If moisture is present in the insulation the electrical resistance between the pins changes (the higher the moisture content, the greater the reduction in resistance). The instrument, which translates it into percentage of dry weight moisture content accurately, measures the level of resistance. The instrument gives moisture readings from 0 ( Dry ) to 33 ( Wet ). The Roofing Contractor is to coordinate with the Roof Consultant to verify the exact areas of wet or nonfunctional roof substrate to be removed prior to performing the Roof Improvements. The Infrared Images and Digital Control Images are presented in the following Sections. The general locations of identified wet areas are shown on the Roof Plan attached to this Report. JIM WHITTEN ROOF CONSULTANTS makes a reasonable dedicated effort to locate, identify and report all thermal anomalies in the low-slope deck roof substrates. However, the limitations of thermography, when combined with existing conditions and situations, prevent us from guaranteeing or warranting the results of our findings. This Report does not purport to set forth all abnormal anomalies nor to indicate that other abnormal anomalies do not exist. Although the findings reported intend to lead to the discovery of defects and/or conditions in need of correction or repair, this Report is not intended, nor shall it be construed, to warrant or represent the existence or nonexistence of any conditions, defect or fact, other than the objective findings contained in the Report. Other conditions may develop over times that were not evident at the time of our site visit. If there are further developments with regard to the roof or if other pertinent documents, that were not available at the time of this report, become available, they should be brought to our attention for review and evaluation. A Statement of Qualifications for Jim Whitten Roof Consultants is attached. If you have any questions or need additional information, contact me at or Prepared by: JCD Page 1 June 8, 2004

3 NON-DESTRUCTIVE TESTING EQUIPMENT PHOTOS Photo A. Tramex Leak Seeker Photo B. Tramex Professional Moisture Meter DOCUMENTATION OF AMBIENT WEATHER CONDITIONS Facility Summary: Client Name: Austin Independent School District Facility Name: Anderson High School Facility Address: 8403 Mesa Drive, Austin, Texas The ambient weather conditions at the time of the Infrared Moisture Scan Survey were documented by the use of a Kestrel 3000 hand held pocket weather meter. The ambient weather conditions at the time of the Infrared Moisture Scan Survey were documented by the use of a Kestrel 3000 hand held pocket weather meter. The instrument documented the following: Average Wind Speed: 2.7 kts. Photo IMG-0002 Air Temperature: 84.8 F Photo IMG-0003 Relative Humidity: 79 % Photo IMG-0004 Dewpoint: 77.3 F Photo IMG-0005 The sky was partly cloudy. Prepared by: JCD Page 2 June 8, 2004

4 INFRARED IMAGES AND DIGITAL CONTROL PHOTOS Image Set Control Photos IR Images Prepared by: JCD Page 3 June 8, 2004

5 INFRARED IMAGES AND DIGITAL CONTROL PHOTOS Image Set Control Photos IR Images Prepared by: JCD Page 4 June 8, 2004

6 INFRARED IMAGES AND DIGITAL CONTROL PHOTOS Image Set Control Photos IR Images No Photo Available Prepared by: JCD Page 5 June 8, 2004

7 INFRARED IMAGES AND DIGITAL CONTROL PHOTOS Image Set Control Photos IR Images Prepared by: JCD Page 6 June 8, 2004

8 I/R IMAGES - Summary Section Name Description Action A I/R Images 1-3 See attached plan for locations Remove Wet Substrate B I/R Images 4-7 (see plan) Remove Wet Substrate S I/R Images 8-12 (see plan) Remove Wet Substrate T I/R Image 13 (see plan) Remove Wet Substrate Q I/R Images (see plan) Remove wet Substrate Existing Roof System Construction Layer Type Description Method of Attachment Surfacing Granules or 3/8 Gravel Hot Asphalt Membrane Mod Bit or BUR Hot Asphalt Insulation Perlite, isocyanurate, or fiberglass Hot Asphalt Base Sheet 40# Coated felt Mechanically Attached Deck Lightweight concrete or metal Overall Core Assessment Core samples were taken at each roof section during our February 12, 2004 Roof Assessment Survey. With the exception of the IR areas noted above, most layers of the insulation assemblies were dry and functional. The core sample at roof section G was wet. Prepared by: JCD Page 7 June 8, 2004

9 Survey Summary Each of the twenty-one Roof Areas of the Facility was scanned. No Thermal Images were captured on those areas not indicating any Thermal Anomalies. All wet and suspected wet areas, identified by the thermal scan and verified with the Tramex, were marked with a bright colored paint, numbered, photographed, and the general location marked on the Roof Plan. A copy of the Roof Plan is attached to this Report. The purposes of this Survey are to: 1. In conjunction with our Roof Condition Assessment, provide AISD with a reliable Roof Asset Management tool for current and future roofing projects planning. 2. Assist the AISD Roofing Contractor in locating and removing the wet insulation and/or substrate prior to installing the new cap sheet or to applying the new roof coating. 3. Comply with the primary roofing materials manufacturer s guarantee requirements that their material will be installed over a dry and suitable substrate. Prepared by: JCD Page 8 June 8, 2004

10 C A B D F G H E K L M N O P Q T R S U V Anderson High School Roof Section Key Plan Prepared by: JCD Page 9 June 8, 2004