MENU

How to Assemble the Tramex Dec Scanner and Moisture Survey Flat Roofing Systems as per ASTM D7954

Video Link

The Tramex Dec Scanner is the Non-Destructive Moisture Scanner for flat and built-up roofing systems. 

The Dec Scanner is Robust, easy to use, and assemble. 

First, remove the base unit from the case by lifting with both grab handles. Next, remove the control panel and the handle. Screw the threaded end of the handle into the Dec Scanner base unit and secure the upper half of the handle with the flip lock. Mount the Control Panel to the telescopic handle and adjust the handgrip to suit. Before using the Dec Scanner always ensure that the electrode mat on the bottom of the instrument is completely secured by making sure that all eight grip screws are fully tightened. Check batteries regularly. It is recommended to always carry spares.

 

To Power On the Instrument

  • First, press the power button on the base unit. The red led will light solidly to indicate a good battery level. Then power on the Control Panel. The red LEDs will flash on both the Control Panel and the base unit to indicate a good connection between the two infrared links.
  • The Dec Scanner has Three Ranges of Sensitivity
  • Range One reads to a depth of approximately one to two inches and is the least sensitive range providing the most shallow depth readings just below the membrane surface. It is most suitable for single-ply and thin roof coverings.
  • Range Two, the mid-range, reads to a maximum depth of approximately three inches and is more suitable for three and four-ply BUR Modified Systems and mineral surface felts.
  • Range Three provides the deepest level readings of approximately 6 inches. This Range can be used for thicker insulation and roof coverings. It is also suitable for gravel and stone surface roofing.

 

The Dec Scanner detects the moisture content in the roof system while non-destructively rolling over the roof surface. Choose the appropriate sensitivity range with the instrument placed over a known dry area then adjust the setpoint knob until the needle is just above zero. If a dry area is not known, position the instrument over a location which is considered to be dry, and adjust the setpoint knob so that the needle points to the mid-scale of 50. Move the instrument around the roof following the directions of lower readings until an area with the lowest readings is found. This should then indicate a relative dry area.

An identified area of high or low moisture may also be checked with extended insulated resistance pins by first puncturing the surface of the roofing membrane with the Tramex hole punch and then using the Tramex Handheld Resistance Probe together with 7" or 15" insulated pins, insert the pins into the insulation for further relative reading. With the Dec Scanner positioned over this relative dry area adjust the setpoint control knob until the needle is just above zero.

 

To perform a survey according to ASTM D7954

  • First, it is necessary to calibrate the equipment on an area of roofing where the surface and subsurface insulation and components are dry.
  • Aggregates on the roof can be left in place but they should be dry and of uniform thickness.
  • A core sample can be taken at this point to evaluate the moisture content, condition, and composition of the roofing system, allowing for the correct scale to be chosen on the Dec Scanner unit.
  • A pin-type moisture meter can be used to evaluate relative moisture conditions of core samples immediately after extraction.
  • Readings should be recorded on the report sheet or App and core samples retained for correlation with Gravimetric Measurements at the verification stage as per ASTM C1616.
  • Proceed by moving the Dec Scanner in a continuous and systematic manner over the roof surface in a grid-like pattern. 
  • Mark areas of concern directly on the roof surface as well as on a roof plan or using the Tramex Meters App. By continuously checking in this way, a complete picture of the roof moisture condition can be obtained quickly.

 

An area of up to 100,000 square feet can be reasonably covered in a day.

Routine testing and diagnosis with the Tramex Dec Scanner helps save millions in Insurance Claims annually through Repairing rather than Replacing Roofing Systems.

Complete Tramex Roofing Kit solutions are available.

Why Risk It? Test with Tramex!