A Passive House is simply a building focused on providing comfort to its inhabitants through highly energy efficient design and construction.
The Passive House (or Passivhaus as it is known in Germany) standard is a way of building that aims to provide maximum occupant comfort with minimal energy use without using complex mechanical systems. This means that maintaining a Passive House is no more complicated than a regular house and possibly even less so as Passive Houses are just built better than standard code minimum construction by using more durable materials and construction practices. This standard also encourages the use of natural materials, which contributes to the health of the buildings occupants.
Passive Houses are on average 70% more energy efficient than a standard house.
HOW DOES IT WORK?
Buildings built to the Passive House standard focus on 4 key points:
An airtight envelope
Required to limit leaks to 0.6 Air Changes per Hour (ACH) to meet standard.
Standard buildings leak at 7 ACH or higher
High levels of insulation (Double to triple the required amount by code)
Proper solar orientation
Continuous, controlled, and filtered ventilation
These 4 elements work synergystically to increase the efficiency of a building to such a high level that they can be heated solely by the heat generated by the occupants, appliances, and the sun.
AREN’T AIRTIGHT BUILDINGS A BAD IDEA?
No, not when properly designed and ventilated. Passive houses have a heat recovery ventilator (HRV) unit installed instead of a convential HVAC unit that continuously brings in fi ltered fresh air
and exhaust stale air from the building. The HRV has a heat exchanger coil that uses the exhaust air to pre-cool or pre-heat the incoming fresh air so the energy used to heat/cool your home is
WHY SHOULD I BUILD A PASSIVE HOUSE?
Buildings in the United States account for around 40% of the energy used, 70% of the electricity consumed, and almost 40% of CO2 emissions produced in this country.
The average passive house heating & cooling utility bill is around $100/yr or less. Compare that to your current home.
Passive houses have excellent indoor air quality and extremely comfortable without drafts or hot/cold spots due to the highly insulated walls and the constant ventilation provided by the HRV.
Passive houses tend to cost more upfront to construct than a standard house, up to 10% more. However since the long-term operating costs are so much lower, payback periods tend to be from 5-10 years depending on location, building size, and usage.
Since Passive Houses use 70% less energy, they require far fewer solar panels than a typical house which makes it much more cost-effective to achieve net-zero or even net-positive status with a much smaller investment in solar panels.
WHAT IF I ALREADY HAVE A HOUSE?
Your current home can be retro-fitted to Passive house standards. This type of renovation can be performed on homes of all ages without changing the appearance of the home unless so desired.
At Zoetic Architecture we strive to bring Passive House level efficiency and construction practices to all of our projects, no matter the budget. Our goal is to provide you with a building that is not only healthier but more comfortable, energy efficient, durable, and beautiful than standard construction.
Check out our article on Passive House featured in the Benton Habitat for Humanity newsletter here or visit the Passive House Institute at phius.org