Author: Matt

Both Passivhaus and EnerPHit are high-performance energy efficiency standards designed to reduce energy use, improve comfort, and lower carbon emissions.

While they share the same core principles, the key difference is that Passivhaus is for new buildings, whereas EnerPHit is specifically for refurbishing existing ones.

Passivhaus: The Gold Standard for New Builds

Passivhaus is a rigorous energy efficiency standard for new buildings, ensuring ultra-low energy consumption and high comfort. It is based on the following principles:

1. Super Insulation – Thick layers of insulation are used in walls, roofs, and floors to minimise heat loss.
2. Airtightness – Buildings are designed to be extremely airtight, preventing warm air from escaping and cold air from entering.
3. High-Quality Windows and Doors – Triple-glazed windows and insulated doors help maintain indoor temperatures.
4. Mechanical Ventilation with Heat Recovery (MVHR) – A ventilation system recovers heat from outgoing air while bringing in fresh air.
5. No Thermal Bridges – The design ensures that there are no weak spots in insulation where heat could escape.

Because Passivhaus is applied to new buildings, it benefits from complete design flexibility to meet these strict standards.

EnerPHit: The Best Standard for Retrofit Projects

EnerPHit is a variation of the Passivhaus standard but designed for upgrading existing buildings. Since older structures often have design limitations, EnerPHit offers a more flexible approach while still delivering impressive energy efficiency improvements. The key features include:

1. Upgraded Insulation – While full Passivhaus insulation levels may not always be possible, EnerPHit still requires significant improvements.
2. Enhanced Airtightness – Gaps and leaks in the building fabric are sealed as much as possible to improve energy performance.
3. Better Windows and Doors – Energy-efficient triple-glazed windows and well-insulated doors help reduce heat loss.
4. Mechanical Ventilation with Heat Recovery (MVHR) – Where feasible, MVHR systems are installed to maintain fresh air without wasting heat.
5. Minimised Thermal Bridges – Efforts are made to reduce thermal bridging, though existing structural constraints may limit full elimination.

Key Differences Between Passivhaus and EnerPHit

Feature	Passivhaus (New Build)	EnerPHit (Retrofit)
Application	New buildings	Existing buildings
Insulation	Maximum levels applied	Improved where possible
Airtightness	Extremely airtight	Improved but may have some limits
Thermal Bridges	Eliminated entirely	Reduced as much as possible
Windows/Doors	Strict triple-glazed standard	Upgraded to high efficiency
Ventilation	Always includes MVHR	MVHR added where practical

Which Standard is Right for You?

• If you are building a new home, Passivhaus is the best option, as it ensures the highest level of energy efficiency from the ground up.
• If you are improving an existing home, EnerPHit provides a practical way to achieve high energy savings while working with existing building constraints.

Passivhaus is for new builds whereas EnerPHit allows old builds to be made more sustainable

Passivhaus and EnerPHit both aim to dramatically cut energy use and improve indoor comfort, but they are designed for different types of projects.

Passivhaus applies to new builds, allowing for complete design control to achieve the highest efficiency standards.

EnerPHit, on the other hand, is a more flexible approach for existing buildings, offering the best possible energy performance within the constraints of the original structure.

Whichever route you take, both standards provide long-term savings, better comfort, and a reduced carbon footprint.

The EnerPHit standard is a high-performance energy efficiency standard specifically designed for refurbishing existing buildings. It is based on the principles of the Passivhaus standard but adapted for older buildings where meeting full Passivhaus requirements may not always be possible.

EnerPHit is recognised as one of the best ways to upgrade an existing property to be more comfortable, energy-efficient, and environmentally friendly.

Key Features of the EnerPHit Standard

To achieve the EnerPHit standard, buildings need to follow similar principles to Passivhaus but with some flexibility to accommodate the challenges of retrofitting. The key elements include:

1. Improved Insulation – The building is upgraded with high-quality insulation to reduce heat loss through the walls, roof, and floors. While it may not always be possible to achieve the same insulation levels as a new Passivhaus, improvements are still significant.
2. Airtightness – Existing buildings are made as airtight as possible by sealing gaps and cracks to prevent unwanted draughts. This helps maintain a stable indoor temperature and reduces the need for excessive heating or cooling.
3. High-Performance Windows and Doors – Installing triple-glazed windows and well-insulated doors greatly improves the building’s energy efficiency by reducing heat loss and preventing cold spots.
4. Mechanical Ventilation with Heat Recovery (MVHR) – An MVHR system is used to provide fresh air while recovering heat from outgoing air. This helps maintain good indoor air quality without losing valuable warmth.
5. Minimising Thermal Bridges – Energy-efficient renovations focus on reducing thermal bridges—areas where heat can escape easily, such as around windows and at junctions between walls and floors.

Benefits of the EnerPHit Standard

• Lower Energy Bills – By improving insulation and airtightness, an EnerPHit home requires much less energy for heating and cooling, leading to significant savings on energy bills.
• More Comfortable Living Spaces – With fewer draughts, cold spots, and overheating, the indoor temperature remains stable throughout the year.
• Better Indoor Air Quality – The use of MVHR ensures a constant supply of fresh, filtered air, reducing humidity and the risk of mould.
• Reduced Carbon Footprint – By using less energy, an EnerPHit building has a lower environmental impact, helping to reduce CO2 emissions.
• Increased Property Value – An energy-efficient home can be more attractive to buyers and may increase in value over time.

Is the EnerPHit Standard Right for Your Home?

The EnerPHit standard is ideal for homeowners looking to make major energy efficiency improvements to an existing building.

While it may not always be possible to achieve full Passivhaus levels of performance, EnerPHit provides a practical and effective way to upgrade an older home.

The process often involves a combination of external and internal insulation, new windows, and improved ventilation systems to significantly enhance comfort and efficiency.

EnerPHit is a great option for those houses where the Passivhaus standard isn’t possible to achieve

EnerPHit is a fantastic option for anyone wanting to transform an existing home into a high-performance, energy-efficient space.

While full Passivhaus certification might not always be possible in older buildings, EnerPHit offers a practical alternative that still delivers excellent results.

With rising energy costs and increasing awareness of sustainability, EnerPHit retrofits are becoming an attractive choice for homeowners in the UK and beyond.

A Passivhaus (or Passive House) is a type of building that is designed to be extremely energy efficient.

It follows a set of principles that help reduce the need for heating and cooling, making it more comfortable and cheaper to run.

The Passivhaus standard was first developed in Germany in the 1990s and has since become popular in many countries, including the UK.

Key Features of a Passivhaus

A Passivhaus is built using a few key principles to achieve its high energy efficiency:

1. Super Insulation – The walls, roof, and floor of a Passivhaus have thick layers of insulation. This helps to keep heat inside during winter and prevent too much heat from entering in summer.
2. Airtightness – Passivhaus buildings are extremely airtight, meaning there are no draughts or leaks that allow warm air to escape. This helps to keep the indoor temperature stable and reduces the need for extra heating.
3. High-Quality Windows and Doors – Special triple-glazed windows and well-insulated doors are used to prevent heat loss and keep the home comfortable all year round.
4. Mechanical Ventilation with Heat Recovery (MVHR) – Since Passivhaus buildings are so airtight, they use a ventilation system that brings in fresh air while recovering heat from outgoing air. This keeps the air inside fresh without losing warmth.
5. Minimal Thermal Bridges – A thermal bridge is a weak point in insulation where heat can escape. Passivhaus designs carefully avoid these, making sure heat stays inside where it’s needed.

Benefits of a Passivhaus

• Lower Energy Bills – Because a Passivhaus uses very little energy for heating and cooling, the cost of running the building is much lower than a traditional home.
• Comfortable Living Environment – The temperature inside stays steady, with no cold draughts or overheating.
• Better Air Quality – The MVHR system ensures a constant supply of fresh, filtered air, which can improve health and well-being.
• Reduced Carbon Footprint – Using less energy means fewer carbon emissions, making Passivhaus buildings more environmentally friendly.
• Quiet and Peaceful – The thick insulation and high-quality windows help to block out noise from outside.

Can Any Home Be a Passivhaus?

New homes can be built to the Passivhaus standard, but existing buildings can also be improved to become more energy efficient.

While it is harder to make an old house completely meet Passivhaus standards, it is possible to renovate homes to get close to these high levels of efficiency.

EnerPHit is the name given to the standard whereby older houses that cannot achieve Passivhaus requirements can be retrofitted to become economically and ecologically optimal.

Passivhaus is an eco-friendly housing standard that helps ensure new houses minimise their impact on the environment

A Passivhaus is a smart choice for anyone looking for a home that is energy efficient, comfortable, and eco-friendly.

While it requires careful design and high-quality materials, the long-term benefits in lower energy costs and improved living conditions make it a worthwhile investment.

As more people look for ways to reduce their energy use and impact on the environment, Passivhaus buildings are likely to become even more popular in the UK and beyond.