It's amazing what you can achieve when you concentrate on insulation and minimising heat loss!
What is PassivHaus?
Passivhaus, also known as Passive House, is a fabric first approach and standard for energy efficiency in buildings and focused on comfort, energy efficiency and wellbeing.. Originating in Germany in the late 1980s, the goal of a Passivhaus is to create a comfortable and energy-efficient living or working environment while minimizing energy consumption and reducing carbon emissions.The Passivhaus standard is all about building the fabric of building to the highest standard and achieving a high level of thermal comfort while significantly reducing the need for space heating or cooling.
Passivhaus or Passive House is based on a set of design principles;
- Super Super insulation and airtightness: Passivhaus buildings are highly insulated, with well-insulated walls, roofs, and floors. Additionally, they have airtight envelopes, reducing the exchange of heat between the inside and outside
- High-performance windows: Passivhaus homes and buildings feature triple-glazed windows with insulated frames to minimize heat loss while maximizing solar gain
- Passivhaus Mechanical ventilation with heat recovery: Passivhaus buildings need highly efficient mechanical ventilation systems with heat recovery to maintain a constant supply of fresh air while recovering and reusing the heat from the outgoing stale air
- Elimination of thermal bridges: These are areas in the building envelope where heat can escape more easily and the Passivhaus design aims to minimize or eliminate thermal bridges to maintain a consistent indoor temperature
- Solar gains and shading: Passivhaus buildings are strategically designed to optimize solar gains during colder months while minimizing overheating during warmer months through effective shading techniques
By designing and achieving installed performance to these principles, Passivhaus buildings can achieve a significant reduction in energy consumption compared to conventional buildings. They typically require up to 90% less heating and cooling energy, leading to lower utility bills and reduced environmental impact.
What role does MVHR (Heat Recovery Ventilation) play in a PassivHaus home or building?
Mechanical Ventilation with Heat Recovery (MVHR) plays a crucial role and is essential in Passivhaus buildings. The ventilation system is a key component designed to maintain a constant supply of fresh air while recovering and reusing the heat from the outgoing stale air
Here's more about the importance of MVHR within the Passivhaus concept:
Ventilation: Passivhaus buildings prioritize airtightness to minimize heat loss. While this is essential for energy efficiency, it also means that natural infiltration of fresh air is significantly reduced but the building and it’s occupants need to breathe. MVHR ensures a controlled and continuous supply of fresh air by mechanically ventilating the building
Heat Recovery: The outgoing stale air from the building is passed through an MVHR unit which has a heat exchanger that transfers the heat from the outgoing air to the incoming fresh air. The heat recovery process significantly reduces the amount of energy required to heat the incoming fresh air during colder months, thereby reducing heating demand even further
Energy Efficiency: Combine with the super insulation, the MVHR recovers and reuses heat that would otherwise be lost, helping to improve the overall energy efficiency of a Passivhaus building. It further reduces the need for conventional heating systems and allows for a substantial reduction in heating and cooling energy consumption.
Comfort and Indoor Air Quality: The MVHR system ensures a constant supply of fresh air while removing stale air, pollutants, and excess moisture from the building. This helps maintain high indoor air quality and creates a healthy and comfortable living or working environment for occupants.
Temperature Regulation: MVHR units often include built-in heat exchangers that can regulate the temperature of the incoming air, allowing for additional control over the indoor climate. This feature helps prevent overheating during warmer months and ensures a balanced and comfortable temperature throughout the year.
Do I need a Passivhaus accredited MVHR Unit?
Passivhaus certification typically involves rigorous testing and verification of the building's energy performance, airtightness, and comfort levels. The certification process ensures that the building meets the stringent standards set by the Passivhaus Institute. To achieve Passivhaus certification, it is required to use an accredited heat recovery system. The Passivhaus standard emphasizes the use of high-quality, energy-efficient components, including Mechanical Ventilation with Heat Recovery (MVHR) systems.
A Passivhaus-accredited heat recovery system has been tested and verified to meet the specific performance criteria required by the Passivhaus standard. They are designed to provide the necessary level of heat recovery and energy efficiency to meet the stringent requirements of a Passivhaus building.
The Air Shop are specialists in MVHR heat recovery for residential homes and offer a wide range of units including Passivhaus accredited units for a range of property sizes.
Can I install a Passivhaus accredited MVHR unit if I’m not building to Passivhaus?
Yes, absolutely - if you are looking for a high specification, high quality system, offering the highest heat recovery efficiencies and additional functions such as pre heaters Passivhaus accredited systems can be used. Remember the full benefits of the MVHR system are relaised when the fabric of the building and insulation levels are good.
If you would like to talk about a MVHR project, Passivhaus accredited or not, our team of MVHR specialists can offer support and advice. Call to speak to the team on 0330 2223 6776 or email sales@theairshop.co.uk
How much does a MVHR system cost? use our 60 second quote tool to understand more about how much a whole system may cost for your home.