Since its been such a hot summer here, I'm going to answer this question with an relevant analogy. Think of a professionally installed geothermal heat pump as a bowl of delicious, smooth ice cream. For me anyway, It's nearly perfect all by itself.
But wait a minute. What about the hot chocolate sauce and sprinkles! That is your home's insulation. If you add it to the mix, you have a real treat.
No matter what type of HVAC system you choose for your new home, the better the exterior is insulated, the more efficient your system will be. A geothermal heat pump is very efficient, but the proper R-value and tightness of your home will lower utility bills and increase the life expectancy of your system. Basically, good insulation lessens the workload. The conditioned air produced is better retained and unconditioned outside air has a harder time infiltrating your home.
A very tight and well-insulated home does require some added consideration. The exact type and R-value being installed needs to be relayed to your geothermal installer. This information is critical in determining the proper size of your HVAC equipment. An incorrectly sized unit can lead to all kinds of problems, no matter how well you have insulated.
Also, a very tight home needs to have fresh outside-air introduced into the living environment to maintain healthy indoor-air quality. A good contractor will recommend one of the many methods to do this, from a simple fresh-air skuttle to a heat-recovery ventilator.
The bottom line — if your home has great insulation, your geo system will produce even lower utility costs and generally last longer. Back to the analogy, definitely go with the chocolate sauce and sprinkles!
This expert insight brought to you by Russ Scott, general manager of Scott-Lee Heating Co. and an Enertech Global LLC geothermal dealer.
Russ Scott has worked for more than 16 years at Scott-Lee Heating Co., and is now the general manager of the business his father co-founded. He received business and creative writing degrees from St. Louis University, is on the S.M.A.C.N.A. - St. Louis Board of Directors, is a Contractor Rep on the Local 36 Apprentice Committee and is involved with the local H.B.A. and A.C.C.A. chapters. Russ enjoys sharing his knowledge of all high-efficient HVAC systems, especially geothermal heat pumps.