What are the 5 principles of a passive house?

Answered by James Kissner

Passive house design is an approach to building that aims to create highly energy-efficient and comfortable homes. There are five key principles that guide passive house design and construction, ensuring that the building performs at its highest potential. These principles are:

1. No thermal bridging: Thermal bridging occurs when there is a break in the insulation layer, allowing heat to escape or enter the building. In passive house design, it is crucial to minimize or eliminate thermal bridging to maintain a consistent indoor temperature. This can be achieved through careful planning and design, ensuring that all building components are properly insulated and sealed.

2. Superior windows: Windows play a significant role in passive house design, as they are responsible for both heat gain and loss. High-performance windows with low U-values and low-emissivity coatings are used to minimize heat transfer. Triple glazing is often employed, along with insulated frames and thermally broken window sills, to further enhance the energy efficiency of the building envelope.

3. Mechanical ventilation with heat recovery: Passive houses rely on mechanical ventilation systems to provide a constant supply of fresh air while recovering the heat from the outgoing stale air. This ensures a healthy indoor environment and reduces the need for additional heating or cooling. Heat recovery ventilation systems use heat exchangers to transfer the heat from the exhaust air to the incoming fresh air, significantly reducing energy consumption.

4. Quality insulation: Insulation is a fundamental aspect of passive house design. High-quality insulation materials with low thermal conductivity are used to prevent heat loss and maintain a comfortable indoor temperature. Insulation is applied to all exterior surfaces, including walls, roof, and foundation, to create a continuous thermal barrier. Proper installation and attention to detail are essential to achieve optimal insulation performance.

5. Airtight construction: Airtightness is crucial in passive house design, as it helps to prevent uncontrolled air leakage, which can result in heat loss and decreased energy efficiency. Airtight construction involves sealing all joints, connections, and openings in the building envelope to create a continuous barrier against air infiltration. This is typically achieved through the use of specialized tapes, membranes, and sealants, combined with meticulous workmanship.

Implementing these five principles requires a holistic approach to building design and construction. Architects, engineers, and builders must work together to ensure that every aspect of the building is carefully considered and optimized for energy efficiency and comfort.

In my personal experience, I have seen the benefits of passive house design firsthand. I worked on a project where these principles were applied, and the results were remarkable. The building maintained a consistent temperature throughout the year, without the need for a traditional heating or cooling system. The occupants reported high levels of comfort and significant energy savings. It was inspiring to witness the positive impact of passive house design and how it can contribute to a more sustainable future.

The five principles of passive house design include eliminating thermal bridging, using superior windows, implementing mechanical ventilation with heat recovery, ensuring quality insulation, and achieving airtight construction. By adhering to these principles, passive houses can achieve remarkable energy efficiency, comfort, and sustainability.