Why Pay Thrice?By Ken Huck on 03/16/2006
Owners of inefficient homes must pay for building, higher utility bills, and the cost of a degraded environment. The key to savings lies in building design.
Over the last four decades, building energy researchers in the United States and abroad have documented that the vast majority of single-family homes waste substantial amounts of energy and money because their thermal insulation systems are poorly designed and constructed.
This dilemma, which includes even new houses that are built to meet today’s codes such as the International Energy Conservation Code (IECC), arises from the failure of building code writers and home designers to recognize that each home is a unique integrated energy system requiring its own thermal design and analysis.
If all of the human family is to share the quality of life now enjoyed by highly industrialized, information age societies, such as ours, we must dedicate ourselves to doing more with less.
Politically influential associations of large homebuilders have also had a role in retarding the improvement of insulation standards. These special-interest groups have persistently and aggressively lobbied against money-saving building code advancements, which would require increases in the thermal performance of new buildings. It is clear that insulation requirements for exterior walls have languished at R-13 far longer than they would have if the interests of homeowners paying the energy bills had been ably represented.
The super-insulated Darmstadt “Passivhaus” (Passive House) and more than 4,000 homes based on its energy design principles are models of what can be achieved when energy use is integrated into building design early: using off-the-shelf components and good thermal design, these affordable, passively heated houses use only 8 percent of the energy for heating that is required to heat conventionally designed, code compliant homes.
Ways to ensure that your home is energy efficient before you build
1. Enlist the support of a building energy designer to help evaluate, select, and specify the most effective energy-efficiency measures (EEM) to ensure that the least expensive and most energy efficient home is constructed.
2. Specify airtight construction and require a blower door test to verify it.
3. Install an efficient, continuously variable speed, energy recovery ventilator (ERV) with demand sensors.
4. Insulate, insulate, insulate! (R-35 walls and R-50 attic in western North Carolina)
5. Place the majority of window area on the south face of the home where winter sun is accessible. Be sure to size south overhangs correctly to avoid summer overheating.
6. Insulate the walls of your foundation or basement and vapor seal the floors.
7. Choose the best PVC-free windows that you can find.
8. Select a knowledgeable builder who is aligned with your energy design goals and who is committed to creating a home for you that serves both your economic interests and the environment.
9. Plan for a future solar electric retrofit by maximizing southern roof faces and keeping them free of penetrations, shadows and obstructions such as gables or chimneys.
10. Consider using a heat pump, preferably a more efficient ground loop type, as a heat source.
We must dedicate ourselves to doing more with less if all of the human family is to share the quality of life we now enjoy. By working with one of the many dedicated members of the WNCGBC to guide your home’s energy design and construction, you will guarantee yourself a home that is comfortable, affordable, and ecologically sustainable. Both you and the environment will benefit!
To learn more about PassivHaus visit: www.passiv.de/07_eng/haupt_e.html
[Ken Huck is the principal energy designer at Susten® Building Energy Solutions. Susten® is an energy design engineering consultancy and a constructor of energy-optimized green buildings.]