They are not fully airtight, allowing moisture to penetrate into the building fabric - a ticking timebomb that will cause structural damage in later years needing costly remedies.  The insulation is poorly fitted with gaps between boards or batts that allow moisture to move around inside, reducing the thermal efficiency by over 50% which ultimately requires more heat input to keep the temperatures stable.  

Simply put, Passivhaus (or Passive House) is a rigorous, internationally recognised building standard focused on energy efficiency, comfort, and sustainability. It originated in Germany in the late 1980s and has since been adopted around the world for both residential and commercial buildings. Building physics are meticulously modelled to ensure that the entire building works together to create the ultimate living or working conditions using minimal energy.

1. Ultra-Low Energy Use
Passivhaus buildings use up to 90% less energy for heating and cooling compared to conventional buildings. This is achieved through smart design, not expensive tech.

2. Airtight Construction
The building envelope (walls, roof, floor) is carefully sealed to prevent drafts and heat loss. This also improves indoor air quality and durability.

3. High-Performance Insulation
The home is wrapped in thick, continuous insulation to keep indoor temperatures stable year-round.

Why Build to Passivhaus Standard?

•  Lower energy bills
•  Consistently comfortable  temperatures
•  Healthier indoor air
•  Reduced carbon footprint
•  Quiet, peaceful interiors
•  Long-term value and durability

Welcome to the future of Living - Today

Imagine a home that maintains a comfortable 21°C (70°F) all year-round, day and night, no matter the weather outside.  Inside, the air is fresh, continuously filtered to remove pollutants and pollen - creating a healthier living environment for you and your family.

There’s no condensation, no mould, and no damp patches in corners or around windows. Drying clothes indoors or enjoying a hot, steamy shower? Go ahead - it is encouraged - it actually helps heat your home.  All this and an average energy bill of just £400 for a spacious family home.  There is no need to crank up the heating in winter, or keep the curtains closed in summer - your home stays naturally comfortable, bright and efficient.

This isn’t a dream of tomorrow.  This is Passivhaus - built for today.

In short, a Passive House is an ultra-low energy building that requires minimal heating or cooling input for most of the year, depending on your climate.  It is highly insulated with no draughts and the home is filled with a constant stream of fresh and filtered air that circulates around the entire house.  No pollen, no pollution.  The general running costs are very low, around 90% than a typical 10-year old house.  Sound too good to be true?  Well read on!   

The Passivhaus Principles

4. Triple-Glazed Windows
Special windows with triple panes and insulated frames help retain heat in winter and block it in summer.

5. Mechanical Ventilation with Heat Recovery (MVHR)
A quiet ventilation system brings in fresh air while recovering heat from outgoing stale air, maintaining comfort and efficiency.

6. Thermal Bridge-Free Design
Construction details are carefully designed to avoid “cold spots” that waste energy and cause condensation or mould.

You can build a new home to meet the Certified Passivhaus standard, or apply Passivhaus principles to improve energy performance without going for full certification.

Passivhaus is a voluntary building standard that is being practiced around the world.  New buildings and extensions are currently governed by a country’s building standards that must be inspected and met by a qualified building inspector.  

In the UK our construction industry is governed by the Building Regulations Act 2010, a set of Approved Documents that cover everything from Health & Safety, fire safety, ventilation, insulation and structural performance as well as security and electronic communications. Architects and builders must design and build to meet these standards.

The English Building Regulations were updated in June 2022 however they still fall short of the levels that are generally being practiced around the world.   The European Commission uses the NZEB Regulations - the Nearly Zero Energy Building Regulations -  following Brexit and our departure from Europe we missed legally complying with these more stringent requirements for our construction industry.  The NZEB Regulations have higher levels of insulation than England and require all new buildings to have 100% renewable energy generation.

Passivhaus vs UK Building Regulations

•  High levels of insulation
•  Fully Airtight building envelope
•  No Thermal Bridges
•  High performance glazing
•  Renewable Energy
•  Maximises free solar gains
•  No performance gap

The Passivhaus building standard is the highest in the world.  By following 5 key principles from the outset, a building uses around 10% of the energy that a standard equivalent uses.

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We spend a vast amount on our cars demanding a high performance from the model, whether miles to the gallon or the time in between charging.  We want air conditioning, ABS, parking assist, cruise control and so on as standard features, yet we seldom demand so much from our homes.

The largest single expense we make in our lives, we don’t give building performance too much thought only wanting a good heating system, lots of natural light and room to carry out our daily activities.

As Climate Change hits around t he world, countries are increasingly applying the Passivhaus Principles as standard practice to both old and new buildings, ensuring their home or workplace performs. Building standards have recently had the biggest global shake up since mudhuts became stone houses where technological advances have allowed us to monitor our traditional building methods.

Many studies have shown that less than 50% of new build homes in England are actually constructed to the intended standard.  This “Performance Gap” as the industry calls it means that whilst Building Regulations are in force and monitored more than half of new builds in larger developments actually meet the full standard when they are finished.  

Thermal envelope with continuous insulation

Airtight design & construction

High performance windows

Ventilation systems

Thermal Bridge-free design

Ultra-low energy building

Buildings That Perform

Not only is it ultra-low energy, a Passive House provides the optimum internal environment circulating fresh air constantly that has been filtered for pollen and pollution.  Moreover, the moisture that is created inside from breathing, bathing, cooking and drying wet laundry actually heats the house, as the heat is recovered before being exhausted warming the incoming filtered air.

Imagine going for a nice hot shower and saying “I’m just going to turn up the heating”!

Individuals from all corners of the construction industry have undertaken rigorous training and examinations to achieve the required qualification to design and build Passive Houses, using maths and physics to calculate the energy balance of the individual building.  

We use the term ‘building’ as the Passivhaus Principles can be applied to ever building size and use from residential homes and apartments to hospitals, schools and shopping malls.

Every computer model is individual to the building, there is no “cut and paste”, even on mass developments.  

The Benefits of a Passive Home

• A passive house creates the optimum healthy living environment, filtered fresh air, no mould or bacteria
• Ultra-low energy consumption keeps fuel bills at 10% of a typical standard house
• A passive house emits very little carbon into the atmosphere, making it virtually Carbon Zero
• Occupiers of passive houses have been proven to be more productive in their daily lives
• A Passive House is always warm, with no cold spots or draughts

What is Passivhaus?

What Makes a Passivhaus Different?

Building or renovating to the Passivhaus Standard is a quality assurance. Unlike our standard buildings a Passivhaus home actually performs exactly as it was designed to do, just like buying a top of the range sports car.

It requires only around 10% of the energy that a typical house would do, saving thousands of pounds on fuel bills and being fully sustainable in this current world of climate change.  And if you add more renewable energy than the house uses you could make it Carbon Positive!

A house built to the Passivhaus Standards is warm and comfortable all year round, with a constant internal temperature of 21°, and the air has been filtered providing the optimum indoor air quality no matter if you are in a densely populated city or out in the countryside.  No more winter duvets.  There are no cold spots in rooms or draughts meaning there is no mould growth.  Constantly moving air means there is no more dusting!

Unlike living in a home built to the current English building standards, drying wet washing indoors and taking hot steamy showers are encouraged, as they actually heat your home!

We like to think of it as living in a Thermos flask: You pour in a hot drink, screw on the lid, and hours later the contents is still warm.  It doesn’t need constant reheating - it just keeps in the heat.  That’s because it’s really well insulated and airtight.  The heat can’t escape, and the cold can’t get in.

Now imagine that same principle, but applied to a building.

A Passivhaus is built with very high levels of insulation, completely airtight construction, and triple-glazed windows.  Instead of heating escaping through draughts, walls, roofing and glass, it stays inside.  And instead of relying on radiators and boilers, a Passivhaus captures and reuses the heat already inside - from people, cooking, appliances and even your shower steam.

Just like a Thermos, once the temperature is comfortable, it takes very little energy to maintain it.

So whilst most homes constantly lose heat through poor insulation, and need to keep adding more through the central heating system, a Passivhaus keeps the warmth in and the cold out - with almost no effort.

The 5 Key Passivhaus Principles

A Fully Insulated Thermal Envelope

The house construction is carefully designed to ensure that there is a continuous and unbroken envelope of insulation wrapped around the structure, with no gaps - especially at key junctions.  Like our Thermos Flask above, this ensures that the warmth is kept inside and the cold outside.  The temperature inside can then be kept at a constant level using the Ventilation System.  Ensuring there are no gaps in the insulation from poor design or on-site fitting removes the potential of mould and bacteria growth as well as structural damage

Airtightness

By creating a fully airtight layer around the structure, moisture from outside cannot penetrate through into the fabric of the building where it can cause structural damage over time.  This moisture would travel towards the inner layers of the building creating cold spots which are the perfect breeding ground for mould and bacteria, creating an unhealthy environment.  Airtight layers can be parge coat plaster, special membranes or part of the insulation system, and every penetration from the outside in such as electrical cables, soil pipes or other services are designed to be sealed with special airtight grommets preventing any unwanted air moving between the outside and inside.

High Performance Glazing, Building Orientation and Form

A Passivhaus uses triple glazing where the performance is considerably greater than traditional double glazing. In cold months the internal air temperature at the glass is only a couple of degrees lower allowing for large areas of glazing to bring the outdoors in and maximise natural daylight. Window design in terms of size and location are fundamental to a Passivhaus, so each window is meticulously modelled ensuring that the glass to frame ratio and its orientation provide the highest capture of solar gains in winter months whilst preventing the house from overheating in the hotter summer months.    

Mechanical Ventilation with Heat Recovery (MVHR)

An airtight building needs to provide fresh air for the occupants and to remove bacteria and smells from cooking and breathing, as well as excess moisture from bathrooms and kitchens.  Ventilation in most traditional homes is provided by trickle vents in windows and mechanical extractor fans in wet areas.  A Passivhaus uses a mechanical system that draws in air from the outside where it is filtered for pollution and pollen before entering a heat exchanger.  The warm moist air from inside is fed through a heat exchanger where it warms up the incoming air before being extracted to the outside. These MVHR systems are the backbone of a Passivhaus and are the only source of heat needed for most of the year, with just a small top up from electric radiators in the coldest months.  They are inexpensive to run and the filters are replaced every 6 months.  Creating an indoor laundry room, an indoor hot tub room, a gym or just taking hot showers are highly encouraged, this moisture is what heats the home!

Thermal Bridge-Free Design

Senior school level physics teaches us that warm air always travels towards cold air, where it cools down to match the colder temperature.  Putting room temperature food in the fridge will cool it down to the internal temperature of the fridge.  When it is colder outside, the cold air enters the building structure at key points where it travels through to the inside.  Like Airtightness above, this air contains moisture which is also the perfect breeding ground for mould and bacteria.  These “Thermal Bridges” occur at junctions where different constructions meet such as the floor to the walls, or the walls to the roof, where windows and doors are fitted, where steelwork is needed for strength and fixings for cladding or balconies.  Any penetration through from the outside to the building structure or the inside is a potential thermal bridge where cold and moisture can travel.  In a Passivhaus, every potential thermal bridge is modelled and designed to ensure it is wrapped in insulation or fixed without causing problems.  

Passivhaus - The Energy Balance

Its All About Balance

The Passivhaus Standards require the energy inputs and outputs to balance.  By entering all the details of the design into the Passivhaus PHPP modelling software, the heat losses vs heat gains are calculated.  Heat losses from the fabric of the building i.e. walls, floors, roofs, windows and ventilation losses, thermal bridges and air infiltration are balanced up against the internal heat gains from occupants and appliances, the solar gains available through the windows and the overall demand for heating and domestic hot water systems.  

Every dimension and detail is input into the software and the Certified Designer/Consultant has to ensure that all heat losses are equal to the heat gains, and that the minimum targets for certification are reached.

Sounds confusing doesn’t it!

It was to us at first, but it is actually a very simple architectural approach to house designing using senior school maths and physics.

Passivhaus - Today’s Living

The Rise of The Mid-Century Modern

The way we live today has changed dramatically since many of our homes were first built. Over the decades—and even centuries—our expectations of what a home should offer have also evolved. In fact, the roots of what we now call a “Passive House” can be traced back to the visionary ideas of world-renowned American architect Frank Lloyd Wright.  

Wright designed the Usonion home, one that was affordable, efficient and in harmony with nature, intended to be practical alternatives to the more ornate and expensive styles of the early 20th Century, designed with the average American family in mind.   

Using flat or gently sloping roofing created lower profiles that blended into the landscape, large indows brought the outside in which were shaded from the heat of the sun on southern and western aspects.

Open-plan layouts allowed the flow and sense of space, with minimalist aesthetics and functional layouts.  Although the term Passive House wouldn’t emerge until decades later in Europe, Wright’s Usonian ideals echo many of the same principles: thermal efficiency, orientation to the sun, reduced mechanical systems, and low-energy living. He believed a home should be “of the hill, not on the hill”.  

As the Passivhaus concept continues to gain momentum in global construction and design, architects around the world are revisiting and reimagining many of Frank Lloyd Wright’s original Usonian principles—adapting them to meet today's passive building standards.  Read more in our Advice Centre on the influences of Frank Lloyd Wright here…..

Passivhaus - To Certify or Not

The Passivhaus Principles can be applied to any building, old or new, and any type of building whether residential or commercial.  Many homes claim to be “eco” or “energy efficient” but only Passivhaus uses strict, measurable performance criteria - verified through independent testing, and following decades of research and analysis.

No Greenwashing.  Just guaranteed results.

Passivhaus certification isn’t just a building standard - it’s a concious choice to prioritise quality, comfort and sustainability at the highest level.  When you choose to build or retrofit your home to certified Passivhaus standards, you’re making a decision to build it right the first time and future-proof your home, knowing that it will perform as it should through high quality building practices and design.

Plus - you get a really cool plaque to go by the front door!

You can of course simply follow the general principles to achieve a well-built and energy-efficient home.  The choice is yours.

We discuss the Certification process in more detail in our Advice Centre.  Read more here

Not only are countries around the world embracing Passivhaus as the gold standard for energy-efficient construction—including progressive regions like Scotland—but local planning authorities across England are increasingly following suit.

Many councils are now requiring new homes to meet Passivhaus or equivalent low-energy standards, recognising it as the most effective way to achieve net-zero targets, reduce energy bills, and ensure long-term comfort and performance in housing.  Bristol, Brighton, Exeter City, Norwich City, Cambridge City and Fareham are just a few examples, and Basildon Borough Council has now included this in the emerging Local Plan that is currently in progress.

National Housebuilders, Barratt Developments,  are also rolling out apartment buildings in London - starting with 728 ultra-efficient units in Acton and High Barnet, as part of a 4,000-home, £1.9billion project in partnership with TFL.

We discuss the Global participation in more detail in our Advice Centre. Read more here

Frank Lloyd Wright design, mid 1900s