It depends upon one's definition, but generally, an eco house is one that seeks to minimise its impact on the environment. An eco house might be achieved once a house is built, for example with the addition of solar panels. A Passivhaus, on the other hand, must be conceived from the design phase and focuses specifically on the level of insulation and air quality.
Which one is right for me?
In general, building an 'eco home' depends on what you'd consider one to be. Environmentally sensitive additions such as air- or ground-source heat pumps or solar panels will make a big difference in how much energy your house consumes. If you want to build a Passivhaus, however, you must have made this clear in the design stage. The specifics regarding air quality and heat loss that affect a home's achievement of the Passivhaus Standard must be addressed in its design. Also, if you want a Passivhaus, be prepared to install a mechanical ventilation and heat recovery system (MVHR) to ensure the air in your home stays fresh.
Essentially, it depends on how rigorous you want to be. The good news is that our
timber-frame and
structural insulated panel (SIPs) systems all achieve high levels of thermal efficiency on their own, so you'll already be saving money on energy.