Our Team


Mark Galbraith
Principal / Owner, EarthSource Geo LLC
Principal / Owner, Galbraith Builders

Mark has 44 years experience as a Design / Builder of custom residential and commercial buildings. As a Built Green and Energy Star Certified Contractor, his projects have included the distinction of having built a LEED certified Platinum house which was the first of its’ kind in southwest Colorado. This house attained an Energy Star net-zero-energy rating utilizing a GSHP, Solar Photovoltaic, and Solar Thermal systems.

Mark completed the Design of Geothermal Systems for Water Source Heat Pumps and Central Systems Course at the University of Wisconsin (Madison) and is an IGSHPA (International Ground Source Heat Pump Association) Certified Installer. He holds certification from McElroy Manufacturing for fusion welding HDPE pipe up to 6” diameter, which will meet the needs of larger commercial projects.

In addition, Mark  received Solar Photovoltaic Systems Training and holds certification from NABCEP (North American Board of Certified Energy Practicitioners). A member of the US Green Build Council (USGBC), Mark has earned accreditation as a LEED AP (Accredited Professional). Mark is a BPI (Building Performance Institute) Certified Energy Auditor and Building Envel0pe Professional.

Other memberships include the Colorado Geo Energy Heat Pump Association, Home Builders Association of Southwest Colorado, and Prior Board Member of  Habitat for Humanity of La Plata County .

Brian Fowler
Principal and owner, GEOSOURCE Distributors

Brian Fowler has been directly involved with the design and installation of over 1,000 geothermal installations since 1987. Prior to founding GeoSource, Mr. Fowler owned and operated a mechanical contracting company specializing in geothermal systems. Brian and his capable staff provide us with invaluable technical expertise, and the sale and support of the best geosource equipment, materials, and tools available.

Gil Davidson
Mechanical Engineer, Consultant

Gil is a retired Mechanical Engineer with a 42 year career in the petroleum refining industry.  All of the principles relating to geothermal heat pumps and efficient energy use can be found in continuous use within an oil refinery, the only difference being the scale of consumption.  The very first tenet of efficient energy use is to use as little energy as possible at the outset.  This translates to cost effective insulation, followed by highly efficient equipment.  These principles apply equally to residential and industrial applications.  He is very enthusiastic about the performance possibilities that exist with ground source heat pump systems in combination with other mechanical heating, cooling, and ventilation systems. His wealth of experience with complex energy systems brings a unique perspective to the systems we will propose in both new and retrofit projects. As a an IGSHPA trained ground source heating and cooling designer / engineer, Gil focuses on the proper system sizing and mechanical design to attain the maximum performance and reliability of our installation.

Pat Bing
Principal / Owner, Air Masters Company, Durango, CO. 

Pat has many years as an HVAC (Heating, ventilation, and Air Conditioning) contractor. He is a trained and certified Ground Source Heat Pump installer, and also installs in-floor radiant heating systems that run in conjunction with our GSHP projects. He is also experienced installing HRV and ERV fresh air ventilation systems.





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EarthSource, LLC is a proud member of the Colorado Geo Energy & Heat Pump Association.


EarthSource Geo, LLC is an IGSHPA Accredited Installer.

Why Should You Consider Installing A GSHP?
A better question should be why not?

Why not install the most cost efficient, reliable, environmentally clean* heating and cooling system available?

*The EPA has called Geothermal heat pump systems (GSHP ’s) the most energy-efficient, environmentally clean, and cost-effective space conditioning systems available.