A Passive house is a low energy dwelling which meets the following criteria.
- Space Heating Demand:≤ 15 kWh/(m²a)
- Building Heating Load:≤ 10 W/m²
- Useful Cooling Demand:≤ 15kWh/(m²a)
- Primary Energy Demand:≤ 120 kWh/(m²a)
- Building Air-tightness:≤ 0.6 ac/h־¹
- Overheating Frequency:≤ 10 %
How the above criteria are met is down to the developer and leaves scope for clever and environmentally conscious solutions which fit the needs of the climate and personal preferences of the occupier. By building to passive house standards or implementing concepts from the passive house ideology you are working towards a low impact and low-cost building, along with many other personal benefits outlined below.
Why Go Passive
Low monthly energy use and big savings
The most obvious upside to a home that requires very little heating and cooling is the monthly energy costs: They’re 60% lower than its 2010 code equivalent outlined below. There is no downside to a building that uses less energy than its code-compliant equivalent.
Passive house does expect higher initial cost, a Study in 2012 found, against 2010 Standards found for a 2-bedroom house with 78m2 Gross Floor Area. Found a 15% cost uplift, this uplift cost will be lower due to both better building standards and the increased uptake in Passivhaus reducing the cost of components.
High indoor air quality
Conventional buildings don’t give you much control over the ventilation because they’re not airtight, As a result, the toxins and particulates from windy days, pollution-spewing trucks driving by, and every piece of off-gassing furniture you own tend to collect and recirculate in your home. In a passive house, the air is completely and methodically exchanged for fresh, filtered air 24 hours a day. The result: Without any effort on your part, potential toxins are given the boot before they reach unhealthy levels.
Since a passive home has a robust ventilation system, it filters out pollen quickly, a major bonus for anyone with allergies. The airtight building also lets far less dust in (and filters out what ends up in the air), meaning less time spent cleaning.
A totally quiet house
Another benefit of airtightness is sound quality. When the doors and windows are shut, the house is almost completely silent. Even ambient noise is reduced since there isn’t central air turning off and on.
Flexibility in building materials
Are you super into reclaimed wood? Or obsessed with recycled denim insulation? Or just really into using as many local materials as possible? Great. With a passive home, you’re not restricted to a certain set of certified materials. The passive house is a performance-based standard. How you meet the performance criteria is entirely up to you. Local and sustainable materials are encouraged, but you (and your builder) have full flexibility to make the materials choices that make sense for your location and budget.
A future-proofed home
While no one can predict exactly where residential building codes will go in the next few decades, the trend is clear: The code will require more energy efficiency and better resource management. By building passive now, your home will more than likely still be compliant in 30, or even 50 years