What is Passive House and how can it be achieved?

Passive House is a sustainable building design approach that aims to create buildings that require minimal energy input to maintain comfortable indoor environments. The Passive House concept originated in Germany in the late 1980s and has since spread worldwide. In this blog post, we will explore what a Passive House is, how it can be achieved in construction, and the benefits of building one.

What is a Passive House?

A Passive House is a building that meets a strict set of energy performance criteria. To be considered a Passive House, a building must meet the following requirements:

1. Space heating demand: The building must have a maximum heating demand of 15 kWh/m2 per year or 10 W/m2 peak load.

2. Energy consumption: The building must use no more than 120 kWh/m2 per year for all energy uses (heating, cooling, hot water, and appliances).

3. Airtightness: The building must have an airtightness of no more than 0.6 air changes per hour at 50 Pascals.

4. Thermal comfort: The building must provide a comfortable indoor environment, with indoor temperatures between 20°C and 25°C, and with no more than 10% of occupied hours outside of these temperature ranges.

5. Indoor air quality: The building must have a ventilation system that provides fresh air while filtering out pollutants and allergens.

Achieving Passive House in Construction

Passive House construction requires careful planning and attention to detail to achieve the high energy efficiency standards. The following design features are essential in achieving a Passive House:

1. Super-insulated building envelope: The building must have a well-insulated envelope with minimal thermal bridges, preventing heat loss through the walls, roof, and floor.

2. High-performance windows: The windows must be triple-glazed, with a low U-value (measuring the rate of heat transfer) and airtight frames to prevent heat loss.

3. Airtight construction: The building must be constructed with airtight materials, with no gaps or leaks in the envelope, to prevent heat loss and infiltration of cold air.

4. Heat recovery ventilation: The building must have a mechanical ventilation system that provides fresh air while recovering heat from the exhaust air, reducing the energy required to heat the building.

5. Passive solar design: The building must be designed to maximize solar gain in the winter and minimize it in the summer, through features such as properly placed windows, shading devices, and thermal mass.

Benefits of Passive House Construction

Passive House construction offers many benefits, including:

1. Reduced energy costs: Passive Houses require minimal energy input for heating and cooling, resulting in significantly lower energy bills.

2. Improved indoor air quality: The ventilation system provides fresh air while filtering out pollutants, allergens, and moisture, improving indoor air quality and reducing the risk of mold growth.

3. Increased comfort: The building envelope and ventilation system work together to maintain a comfortable indoor environment, with no cold spots or drafts.

4. Reduced environmental impact: Passive House construction reduces greenhouse gas emissions, as the energy required to heat and cool the building is significantly reduced.

Passive House construction offers a sustainable and energy-efficient approach to building design. Achieving Passive House requires careful planning and attention to detail, with a focus on insulation, airtightness, ventilation, and solar design. The benefits of Passive House construction include reduced energy costs, improved indoor air quality, increased comfort, and a reduced environmental impact. As we move towards a more sustainable future, Passive House construction offers a promising solution for reducing energy consumption and greenhouse gas emissions in the built environment.