This post is part of our series that shares questions we regularly receive about Passivhaus and low energy construction. We will be posting a new one every week. Explore our Blog to learn all about why designing buildings to low energy standards like Passivhaus delivers a lot more than just energy savings.
In the realm of sustainable architecture, the Passivhaus standard has emerged as a shining example of energy-efficient building design. Developed in Germany in the late 20th century, Passivhaus (or Passive House) principles emphasise reducing energy consumption while maintaining a comfortable living environment. One of the key questions that often arises when considering Passivhaus construction is, "Are there specific types of materials needed for Passivhaus?"
In this blog post, we'll explore the essential materials that play a vital role in achieving the Passivhaus standard and creating homes that are both eco-friendly and comfortable.
Insulation materials
Insulation is a cornerstone of Passivhaus construction. The chosen insulation materials must have a high thermal resistance (R-value) to minimise heat loss. Common insulation materials used in Passivhaus include:
High-Density Insulation: Materials like expanded polystyrene (EPS) or extruded polystyrene (XPS) foam boards provide excellent thermal insulation and are resistant to moisture.
Cellulose Insulation: Made from recycled newspaper and treated with fire retardants, cellulose insulation is an eco-friendly option that offers good thermal performance.
Mineral Wool: This type of insulation, often made from rock or slag, is known for its fire resistance, high R-value and recyclability.
Airtight building envelope materials
Creating an airtight building envelope is crucial for Passivhaus construction to prevent air leakage. Materials that help achieve this include:
Airtight Membranes: These specialised membranes are applied to the building's structure to create an airtight barrier.
Sealants and Tapes: High-quality sealants and tapes are used to seal gaps, joints, and seams, ensuring airtightness.
High-performance windows and doors
Passivhaus buildings rely on energy-efficient windows and doors to minimise heat loss. Triple-glazed windows with low U-values and thermally broken frames are commonly used.
Controlled ventilation systems
Passivhaus relies on controlled mechanical ventilation with heat recovery (MVHR) systems to maintain indoor air quality while minimising energy loss. These systems require efficient heat exchangers and ductwork.
Thermal bridge-free construction materials
Thermal bridges can compromise the energy performance of a Passivhaus. To mitigate this, we select materials that minimise thermal bridging. Straw bale panels, prefabricated timber panel and CompacFoam (an insulating material with structural properties) are examples of materials that help achieve thermal bridge-free construction.
Conclusion
Passivhaus construction demands specific types of materials carefully chosen to meet its stringent energy efficiency and comfort criteria. From superior insulation materials to airtight building envelopes, high-performance windows, and controlled ventilation systems, every element plays a crucial role in achieving the Passivhaus standard.
Building a Passivhaus not only reduces energy consumption and lowers carbon emissions but also provides occupants with a comfortable and healthy living environment. The materials used in Passivhaus construction not only contribute to achieving these goals but also promote sustainability and long-term cost savings. As the world continues to prioritise environmental conservation and energy efficiency, Passivhaus construction and its material choices serve as a great example of responsible architecture for the future.