What is Passivhaus?
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Passivhaus, also known as Passive House, is an internationally recognised approach to building highly energy-efficient homes. Designed to maximise comfort and indoor air quality, Passivhaus principles minimise energy consumption for heating and cooling, helping to create healthier living environments with significantly reduced running costs and carbon emissions. Through intelligent design and high-performance construction, Passivhaus homes offer a sustainable and future-proof solution for modern living.
Through our collaboration with Econekt, Urban Eco Homes provides the on-site installation of Passive Slab insulated foundation systems, bringing together Econekt's specialist low-energy building systems and technical expertise with Urban's practical groundworks and construction experience. Passive Slab by Econekt is a high-performance insulated foundation system specifically engineered for low-energy and Passivhaus homes. Continuous insulation around the foundation helps significantly reduce thermal bridging and heat loss through the ground, providing the ideal starting point for a high-performance building envelope. The collaboration provides clients with a joined-up approach. Econekt provides the specialist system, design and technical support, while Urban Eco Homes brings the design to life on site, coordinating the installation with the groundworks, services and structure above. Our experience with ICF construction also makes Passive Slab a natural fit for projects where both foundation and wall performance need to be considered together. Whether we are appointed for the Passive Slab installation alone, the associated groundworks, or a wider ICF structural shell package, the Urban Eco Homes and Econekt collaboration provides clients with specialist knowledge backed by experienced on-site delivery.

Our Services
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The Origins of Passivhaus Building
First developed in Germany in the late ’80s, Passivhaus building was pioneered by Professors Wolfgang Fiest and Bo Adamson, with the first homes built in the ’90s. While they were the first to build what we know as Passivhaus homes today, Fiest and Adamson’s revelation focuses on the research and development of builders in North America during the ’70s. They looked to construct homes that used little to no energy, using the sun as a primary heat source – the critical requirements of Passivhaus building today. The first actual Passivhaus construction to the standard that we know today was four terraced townhouses in Darmstadt, Germany. Built in 1990 by architectural firm Bott, Ridder & Westermeyer, their clients occupied the homes the following year. This was a pivotal point in low-energy construction and paved the way for the now-booming industry in modern times.
Reduced Energy Demand
The Passivhaus Trust note that these fantastic homes achieve around a 75% reduction in annual heating requirements compared to other UK new-build homes built by standard practices – with homes built in warmer climates requiring even less energy. How is this achieved? Well, it’s quite simple... Passivhaus building focuses on reducing heat loss to the point that it needs little to no heating, with this achieved from solar heat, appliances in the home and occupants of the Passivhaus house. These are teamed with impeccable building standards such as high insulation levels using Insulated Concrete Formwork (ICF) and minimal thermal bridges to achieve a significant reduction in heating demand.
What Are Passivhaus Standards?
The requirements for your home to meet Passivhaus Standards. The Passive House Institute detail them as follows: * Space Heating Energy Demand should not exceed 15 kWh per m2 of net living space per year. * The Renewable Primary Energy Demand, the total energy to be required for all of your home’s domestic applications, must not exceed 60 kWh per m2. * Looking at Airtightness, a maximum of 0.6 air changes per hour is allowed at 50 Pascals pressure (ACH50). This will be verified with an onsite pressure test. * Thermal comfort should be met for all living areas for energy-efficient houses in both summer and winter seasons. This shouldn’t exceed 25°C for any more than 10% of the hours in a year.
Benefits of a Certified Passivhaus Home
There are endless benefits of having a Passivhaus-certified home. Click to see the advantages of Passivhaus building. Low running costs: This is a crucial benefit to the user more than anything else. Passivhaus homeowners will see a considerable reduction in their running costs. As aforementioned, owners will tend to see prices reflecting as little as 25% of a typical new-build home, with many seeing even less than this in certain climates. Sustainability: A key benefit to our beautiful planet and the user again. An obvious one too! If we are using less energy, this will, in turn, have a significant impact on planet Earth, with a massive reduction in carbon emissions. Another implication to consider also looks at the decrease in labour and construction – if fewer of these are used, homes will require less energy when building them. Longevity: The lifecycle of the home itself. Passivhaus homes are known for their unrivalled longevity — houses built for the future that stand the test of time. Healthy Environment: While not an essential requirement for Passivhaus building standards, we still feel that a healthy environment for users is imperative for the building process. Improved air quality, thermal comfort, and balanced moisture and humidity levels are all enjoyed in a Passivhaus home.
Passivhaus Construction
Passivhaus is in the DNA of everything we do when delivering this service. We can offer a full-service self-build project or help at specific job points. We offer everything from a full Turnkey service to supply and site assistance (plus everything in-between). We also provide the ability to certify your project, working closely with our partner Passive House School. They are able to offer a full Passivhaus certification on your new home, post-construction, through the use of the Passive House Planning Package (PHPP). A full list of our services can be found here.

Urban Eco Homes offers a specialist ICF structural shell service, providing clients with a flexible alternative to a complete Design & Build package. We can take a project from prepared foundations through to a fully formed, weathertight structural shell, giving the client the freedom to decide how and when the remaining stages of their home are completed. Our shell packages can incorporate the complete Izodom ICF wall structure by Econekt , reinforced concrete, structural steelwork, beam-and-block ground floors, Posi-Joist intermediate floors, roof structures, windows and external doors. By coordinating these key structural elements as one package, we can manage the critical interfaces between the ICF system, floors, openings and roof to create a robust, accurate and high-performance building envelope. The extent of the package can be tailored to each project. For some clients, we construct the ICF structural walls and floors only; for others, we continue through the roof construction and installation of high-performance windows and doors to create a secure, weathertight shell ready for the internal fit-out. Once the shell is complete, the client has complete flexibility over the next stage. Urban Eco Homes can be instructed to continue the project through to completion, the remaining works can be handed over to another contractor, or the client can take control of the fit-out themselves and complete their home at their own pace. This makes the structural shell route particularly suited to self-builders who want specialist support through the technically demanding stages without committing to a full turnkey build. Across our ICF shell projects, our focus remains the same: structural accuracy, careful detailing, thermal performance and coordination between trades and systems. The result is a high-quality ICF structure that provides a solid foundation for the client to take their project in whichever direction suits them. Typical Shell Package: ICF walls · Reinforced concrete · Structural steelwork · Beam & block floors · Posi-Joist intermediate floors · Roof structures · Windows & external doors · Weathertight shell · Flexible handover options
Building with Izodom ICF Technology
At Urban Ecohomes, we specialise in delivering high-performance, energy-efficient homes using the award-winning Izodom Insulated Concrete Formwork (ICF) system. Through our trusted partnership with Econekt, the exclusive UK distributor of Izodom products, we provide clients with access to one of the most advanced construction systems available for low-energy and Passivhaus homes.

Why Choose Izodom?
Izodom ICF combines structural strength with exceptional thermal performance, creating homes that are warmer, quieter and significantly more energy efficient than traditional construction methods. Designed to reduce heat loss, eliminate thermal bridging and improve airtightness, the system helps lower energy bills while providing year-round comfort.
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Outstanding energy efficiency with U-values as low as 0.10 W/m²K
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Reduced heating costs and lower carbon emissions
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Faster construction compared with traditional methods
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Exceptional thermal and acoustic insulation
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Airtight construction for maximum performance
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Durable reinforced concrete structure designed to last
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Suitable for Low-Energy, Passivhaus and Passivhaus Plus homes
More about Izodom 2000 Polska
Izodom 2000 Polska are unrivalled in ICF construction products, which is one of the many reasons we at Econekt decided to partner with them exclusively in the United Kingdom and Ireland. Now with production and manufacturing facilities globally, Izodom produces one of the most advanced ICF construction systems available on the market. They have a range of over one hundred and forty individual system components; through three levels of energy performance, there is an Izodom product option for every project. Famed for their award-winning manufacturing, Izodom 2000 Polska offers insulated concrete formwork, specialist insulation panels and other key foam components for your exciting project. They are highly regarded for their seamless innovation and focus on energy efficiency.
Izodom Insulated Concrete Formwork (ICF) Walling Systems
Izodom currently offer three levels of walling systems for your self-build project, each with varying insulating properties and external wall thicknesses.
Benefits of ICF construction?
There are many benefits of using Insulated Concrete Formwork systems in your self-build. Here are the key advantages of using the system over other systems on the market. Thermal Insulation: You will often find that when using Insulated Concrete Formwork blocks for your self-build project, this can completely omit the requirement for other sources of insulation, such as more traditionally used means like fibreglass, mineral wool, cellulose or polyurethane foam. Acoustic Insulation: As well as thermal insulation, you will also find that ICF construction allows for a considerable reduction in acoustic insulation requirements in homes. This ensures that the insulation can reduce noise levels to a minimum between rooms. Perfect for homes to those with a particular musical talent or buildings that need to keep noise levels between themselves and neighbours to a minimum. Efficiency: A key advantage of using an ICF construction system is its use efficiency in the build process. This is mainly down to the ease of use and installation with ICF materials; this ensures less of a requirement for labour and materials, rendering your project far more economical in the long run. **Energy Benefits:** Depending on which type of walling system and other ICF construction products you decide on, your dream home could be enjoying little-to-no running costs in terms of heating. ICF’s insulation properties mean that your home’s energy can be generated from things like body heat and appliances, omitting the requirement for central heating systems in many cases. **Integrity:** ICF construction systems enjoy a wealth of benefits when considering the structure of your self-build project. You can enjoy peace of mind knowing that your materials are impenetrable to factors such as mould, rot, adverse weather and dampness. ICF systems have long been hailed as a better alternative to traditional materials such as wood when conducting a self-build project. **Air Tightness:** Airtightness is generally an area of concern or risk when building your home. However, when working with ICF construction, the structural concrete core provides the structural integrity of the house and the primary air barrier, reducing the risk of this tiresome process and allowing more time to be spent on the penetrations or window and door openings. ICF-constructed homes can achieve an air change rate of less than one change with no extra attention.
Izodom Foundation Slabs
Another key product that Izodom 2000 Polska and Econekt offer is their foundation slab system. These slabs have been used in place of traditional continuous strip footings and foundation walls. Ground slabs are typically cast at the construction site and reinforced with steel mesh or steel fibre. Izodom ground slabs can achieve varied shapes due to the manufacturing process used to make them, unlike those offered by some other companies. The usual thickness of slab insulation is 250mm, but this can be increased by up to 150mm in some cases or reduced to only 150mm at the request of the project designer.
Benefits of Izodom Foundation Slabs
There are several key benefits to using Izodom foundation slabs in your self-build project. **Speed & Ease of Execution:** The straightforward structure of the foundation slabs ensures that they are easy to install and reduces the possibility of on-site mistakes or errors when laying them. You will also benefit from a reduced installation time of up to three days, mainly due to the specific components used in their construction. Each Izodom and Econekt foundation slab is delivered to the site pre-cut and formed, together with an installation guide. This ensures that no on-site modification is required and that the foundation components interlock across both their vertical and horizontal planes. **Damp & Thermal Protection:** Izodom foundation slabs remove the need to apply separate horizontal and vertical insulation, as required when constructing traditional foundation walls and continuous strip footings. This makes insulation much easier and provides your self-build project with improved protection against both thermal and damp elements. **Stability:** The Izodom foundation slab is a major structural component of your self-build project. It provides unrivalled stability compared with other conventional designs, such as foundation walls and continuous strip footings. **Slab Positioning:** As our slabs only need to be positioned at a depth of 0.5m, the time and depth required for excavation are significantly reduced for your self-build project.

















