Something passive is usually seen as the worse version than its active one. However, such kind of thing doesn’t apply to housings. Passive house is considered a better and more modern version of housing, compared to its active opposite.
Passive house, or so-called passivhaus in Germany, is a building built with energy-efficiency standard that can be reached by modifying its architectural design. Compared to conventional active house, passive house can help us save more energy without ignoring our requirement for comforts.
Many modern buildings have been built with such standard, and the concept has been adapted by many constructional works all around the world. Not only because it is energy-efficient, but also because it is more comfortable, affordable, and ecologically friendlier.
Want to know more about this building concept? Well, here in this article we are going to talk about the concept indeed.
Better Than Just Low
We have been familiar with the term low-energy building. This kind of building is characterized by its technical features and energy-efficient design. Low-energy building is often considered as sustainable architecture because of those features.
Passive house adopts the same features, but in slightly different way. While low-energy building is built based on its energy consumption management, passive house is built based on its passiveness toward energy consumption.
Low-energy buildings are built to make sure that we consume lowest additional energy possible for our comfort. While passive buildings are built to make sure we don’t need to use features that require additional energy consumption.
In example, low-energy buildings still require constant heating or cooling to give us the comfort, even though the energy consumed is far lower than conventional buildings. While in passive buildings, such kind of energy consumption is only required for back-ups.
Passive buildings can save up to 75% more energy for heating compared to low-energy buildings. But it doesn’t mean that passive houses are less comfortable to live in, because the needs for heating is fulfilled from its components and ventilation system.
Passive house pretty much offers everything we put in our personal criteria for comfortable housing. But all of those criteria are fulfilled with the lowest possible additional energy consumption, just as mentioned above.
The presence of International Passivhaus Standard makes sure we actually get what we want and what we need. Various construction techniques and technologies have also specifically been developed as insurance the standard is fulfilled.
There are four basic criteria that need to be fulfilled for building the right passive house according to the standard. Those criteria are space heating energy demand, primary energy consumption, airtightness, and thermal comfort.
The demand for energy used for space heating in passive house must not exceed 15 kWh/m2, which is far below typical house with 100 kWh/m2. While primary energy consumption such as heating, hot water, and domestic electricity must not exceed 60 kWh/m2.
Airtightness and thermal comfort features should also be considered for comfortable living. No more than 0.6 air changes per hour is allowed at 50 Pascal of pressure, and no more than 10% of given year is over 25 degrees Celsius.
How Does It Work?
How can we fulfill those criteria and get comfortable result that’s affordable too? There are five principles we can follow to ensure all those criteria fulfilled: no thermal bridging, high-quality insulation, superior windows, airtight construction, and mechanical ventilation.
Avoiding thermal bridging and applying high-quality insulation are key points. We need to make sure that stable indoor temperature is not affected by outside temperature by eliminating gaps between walls, floor, and roof. Additional insulator like stone wool is sometimes needed for total insulation from outside temperature.
The flow of air should also be controlled by using highest quality windows that will only allow heat to get out or enter when we need it. The construction itself should not allow any airflow to happen without our consent.
High quality ventilation that allows heat recovery is the final principle that we need to follow. High quality ventilation that we need is the one able to transfer fresh air coming and transfer out used air from the inside without transferring too much heat.
When all those principals are applied, we don’t really need additional heat sources like furnaces or boiler. Additional heat or cooling is still allowed, especially for those who live in areas with extreme climate, but it is suggested that it uses sustainable energy sources like solar panels.
Passive house is considered more beneficial to us, compared to both conventional and typical low-energy house. Energy efficiency is the first benefit that we will easily recognize. Passive house consumes about 75% less energy compared to typical low-energy house, which is already so low, in term of general heating.
In addition to that, as mentioned above, passive house is not only about saving energy, it is about comfort too. The presence of International Passivhaus Standard makes sure that every single passivhaus built doesn’t ignore this important aspect.
And one of the most frequently asked question about passive house is the cost to afford it. Building a home with high quality materials like mentioned in the criteria above should cost more than typical conventional house.
It indeed is. But actually, the extra cash we spend on high quality materials and extra components makes maintenance cost of passive house significantly lower. A whole-life cycle cost analysis carried out by EnCraft discovered that passive house has lower lifecycle cost than conventionally built house.
High quality materials also ensure that it can be sold at later time with higher price. In addition to that, by consuming lower energy, you can save a lot of money from electricity. Thus, even though it costs a little bit more in the construction, but passive house is actually more beneficial for longer range of time.
If you want to build a passive house, or maybe renovate your own house to make it a passive one, you can easily find more information on the internet, because it is actually a trend nowadays. Are you interested?