Expert Witness Services

District Heating and Cooling

Geothermal Heat Pumps

Heat Transfer in Soil Systems

Cold Regions Heat Transfer





Instrumentation plan for heat loss measurement on a shallow concrete trench

Instrumentation plan for heat loss measurement on a shallow concrete trench heat distribution system (Ft. Jackson, SC).

IR camera cart for surveys of buried heat distribution systems

GWA Research conducts infrared (IR) surveys of buried heat distribution systems from the ground surface using this specially fabricated IR camera cart. This allows for higher resolution than aerial surveys and the ability to precisely mark the location of abnormalities on the surface.  With the camera at a height of approximately 10 feet perspective is much better than with a hand held camera and the angle for viewing is closer to the ideal normal angle. 

Heat flow sensors and thermocouples attached to a conduit

Heat flow sensors and thermocouples attached to a common conduit type high temperature water heat distribution system. (Ft. Jackson, SC).

Leak Persistence Test Chart

A leak persistence chart prepared by GWA Research LLC as part of expert witness services in a thermal damage lawsuit. Such graphs, specific to each incident of course, allow limits to be set on what impacts could be expected from a steam leak for example after various persistence times at various distances.

District Heating and Cooling


In district heating and cooling (DHC) Gary Phetteplace’s contributions and experience span his entire 34+ year career.  He has developed several models for optimal design of DHC systems and has conducted a number of field studies that have instrumented and measured the performance of both existing and new distribution systems.  Gary Phetteplace either acted as the principal investigator or a participant in extensive field forensics programs of the Department of Defense (DoD) spanning 25 years.  These efforts included approximately 100 excavations of operating systems.  He was an adviser to the Federal Agency Committee for Underground Heat Distribution Systems from late 1970’s until the committee’s dissolution in approximately 2000.  In addition to all branches of DoD and the Veterans Administration, Gary Phetteplace has acted as a paid consultant to EPA, DoE, NASA, and numerous private entities on heat distribution systems.  He has contributed to many DoD guide specifications for construction and procurement and has authored major sections of some of these documents.  Gary Phetteplace has been the long-standing editor and Handbook Committee Chairman for American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) Technical Committee TC6.2, District Heating and Cooling.  In that capacity he contributed all the thermal and hydraulic analysis sections as well as other portions for many past editions and the current 2008 edition of the ASHRAE Handbook, HVAC Systems and Equipment Volume, Chapter 11.

A team lead by GWA Research LLC was selected by ASHRAE to author design guides for DHC and District Cooling.

Gary Phetteplace has done expert witness work in the areas of thermal damage, heat loss assessment, and standard of care in design and construction of heat distribution systems.

Eielson, Utilidor lid

A shallow utilidor under construction in interior Alaska. Gary Phetteplace consulted on the design and subsequently developed and executed an instrumentation plan that was used to thermally validate the design.

© 2016 GWA Research, LLC         December 28, 2016