CabBauge cut away wall section showing structural mix and insulating mix, sloping mechanical key between layers and hemp fibres used in reinforcing layers

CobBauge Guest Post

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INTRODUCTION

CobBauge is about reimagining one of the world’s oldest building methods for today’s needs. For centuries, homes built from earth have kept people warm in winter and cool in summer, while leaving almost no carbon footprint.

Yet in modern times, these natural homes struggled to meet strict building regulations. The CobBauge project brings together British and French expertise to prove that earth can still build strong, healthy, and sustainable homes for the future.

Problems and solutions:

ENERGY & CARBON (CO2) REDUCTION: (problem)

Buildings are energy-hungry, using about 40% of all energy in Europe. Of that, around 60% goes just to heating.

This not only drives up household bills but also releases huge amounts of carbon. CobBauge offers a natural way to cut this waste while keeping homes comfortable.

ENERGY EFFICIENCY DIRECTIVE 2012/27/EU (EED) and 2018 update

The EU has set strict rules to cut energy use through the Energy Efficiency Directive (2012/27/EU), updated in 2018.

Under the European Green Deal, the goal is even higher: to make Europe the first climate-neutral continent by 2050.

To get there, the EU has revised the Directive so that by 2030, greenhouse gas emissions must fall by at least 55% compared with 1990 levels.

The European Commission is pushing for major cuts in the energy buildings use, which means better insulation is essential. But as insulation improves and energy use drops, the impact of the materials themselves becomes more important. That’s why choosing low-energy, low-carbon, and natural materials: like earth, timber, and other bio-based options: is key to building a truly sustainable future.

2021 UK Environment Bill

The UK has committed by law to reach net zero greenhouse gas emissions by 2050.

At one stage, proposals linked to the Environment Bill suggested that all new buildings should be net zero carbon by 2030, and the entire building stock by 2050.

These specific targets have not yet been made binding, but the direction of travel is clear. Work is under way on a UK Net Zero Carbon Buildings Standard to guide future construction.

Meanwhile, the EU is moving faster: by 2028, large new buildings must undergo whole-life carbon assessments, and by 2030, this will apply to all new buildings.

The UK is currently piloting similar approaches, but without binding limits

2023 Energy Performance of Buildings Directive (EPBD):

The Energy Performance of Buildings Directive (EPBD) is part of the EU’s ‘Fit for 55’ package. It calls on every member state to create a national building renovation plan and sets minimum performance standards so that the worst non-residential buildings must reach class F by 2030 and class E by 2033.

The Directive also promotes one-stop shops, renovation passports, and new financial tools to help banks support energy-efficient upgrades. After the war in Ukraine, the EU added measures such as ensuring new buildings are solar-ready and fitted with solar installations.

The recast of the Energy Performance of Buildings Directive (EPBD) is a major plan to renovate Europe’s building stock, cut energy use, reduce emissions, and achieve climate-neutral buildings by 2050.

Buildings are responsible for about 40% of the EU’s energy use and 36% of its CO₂ emissions, and three out of four are still energy inefficient.

A key advance is the focus on embodied carbon, which makes up 10–25% of a building’s total footprint but has long been overlooked. Heavy industries like cement and steel drive much of these emissions. The recast now requires embodied carbon to be measured and reduced across the full building life cycle.

The European Parliament has called for an EU-wide framework to calculate life-cycle Global Warming Potential (GWP), with Member States publishing roadmaps that set renovation targets and limits on embodied carbon. Each country must prepare a national renovation plan suited to its building stock.

Low embodied everything

As buildings become better insulated and use less energy day to day, the impact of the materials themselves becomes more significant. That’s why the choice of building methods matters. Using low-energy, low-carbon, low-chemistry, and water-efficient materials—such as earth, timber, and other bio-based options—offers a smarter path to sustainable construction.

The problems

Business as usual:

EU rules once pushed the UK to improve environmental standards, tackling ozone protection, waste, greenhouse gases, and air quality. With Brexit and deregulation, there’s a risk of slipping back into profit-first behaviour. Powerful lobbies often resist change, slowing legislation that could meet EU and global climate goals.

Governance:

Without strong governance, poor practices return. Green concerns are dismissed as alarmist, while inconsistent policies create unintended and harmful outcomes.

Business economics:

Fiduciary rules, meant to ensure profit for shareholders, too often drive decisions that harm health, the environment, and long-term sustainability.

Industry Preoccupations:

The focus is on cutting costs and boosting profits, often at the expense of safety and quality. The Grenfell fire is one tragic example. Buildings are designed to minimum standards, with little thought for long-term costs or summer overheating. Substituting high-performing products with cheaper, less effective materials is common, all to protect existing supply chains.

Environmental and social:

“Saving the planet” is too often mocked, even though it’s about ensuring people and nature can thrive here.

Construction and profits:

Low-cost, high-profit models push manufacturers & installers toward cheaper processes that harm workers and the environment. Preferring products that need less labour and more chemistry, the industry sacrifices sustainability.

Manufacturing of construction materials:

Many low-cost materials come with high embodied energy, carbon, chemistry, water use, and waste. Every stage—extraction, production, installation, and disposal—adds to the footprint.

Green or violet:

Conventional construction can be seen as “violet” (conventional), while greener alternatives are growing. Green materials may cost more today, but as production scales up, they can compete. They often have different properties that need to be properly understood and applied.

Green materials, green properties:

Bio-based and often carbon negative
Store carbon through photosynthesis
Hygroscopic and vapour-open, supporting healthy moisture management
Provide thermal mass and decrement delay to reduce overheating
Improve indoor air quality and humidity balance

Modern methods of construction (MMC):

Prefabrication can reduce waste and improve factory quality but requires high precision on-site, which the industry often lacks.

The government aims for 20% of new housing to use MMC, expecting lower costs, faster delivery, and reduced carbon.

Government and modern methods of construction:

In its own estate and in housing, the government wants lower costs, lower carbon, and faster delivery. It sees MMC as a near-universal way to meet those goals and has said it wants 20% of housing to be delivered via MMC

Unintended consequences:

Thin MMC walls often rely on plastic insulation, which traps heat. Once solar heat enters a roof, upper floor or external walls, it cannot escape, causing overheating. This in turn drives reliance on energy-intensive air conditioning as a retrofit and even as part of initial design.

The problem
To cut CO₂ emissions, we need to move away from many “violet” (conventional) materials. A few account for a huge share of man-made CO₂:

Cement: 9% (chemistry + energy)
Steel: 7% (plus GGBS by-product)
Plastics: 4.5%
Aluminium: 3%

Embodied CO₂ makes up 10–25% of a building’s footprint, and in very efficient buildings it can rise above 95% (RICS Redefining Zero).

At the same time, we must design buildings that are energy-efficient, well insulated, thermal-bridge free, and airtight to cut fossil fuel heating. Fossil fuels remain a major driver of emissions:

– Natural gas: 20%
– Oil: 36%
– Coal: 43%

We also need to avoid materials with high manufacturing energy unless powered entirely by renewables, such as fired clay brick, terracotta, ceramics, Aerated Autoclaved Concrete (AAC) blocks, heat-treated glass, and energy-intensive insulation. Conventional systems like cement concrete, screeds, masonry, and steel framing further lock in emissions.

The solution
The way forward is to use low-carbon or carbon-negative materials. These include:

Bio-based options: timber, timber fibre, plant fibres, plant oils, bamboo
Mineral and earth-based: stone, subsoil, rammed earth, cob, CobBauge
Wood technologies: light timber frame, post-and-beam, solid wood, Cross-Laminated Timber (CLT), dowelled panels, glulam (though higher chemistry adhesives)
Traditional systems: adobe, drystone, turf & stone wall.

This range may seem limited, but these methods point us toward a robust path for solving the CO₂ challenge in construction.

INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE (IPCC)

Climate change impacts and risks

Key risks

Mortality and morbidity of people due to heat
Heatwaves put lives at risk. Traditional cob walls help keep interiors cool, but only if the roof also blocks radiant heat. With improved design, CobBauge strengthens this natural protection against summer overheating.

2 Heat and drought stress on crops

Crop by-products provide essential fibres for repairing traditional cob and making CobBauge. But in the long term, climate change, pesticide use, and wildfires could threaten crop yields — and with them, the availability of these vital ingredients.

3 Water scarcity

Water is central to the CobBauge mix, but most of it naturally evaporates back into the air. Any leftover material can safely return to the ground.

By using local subsoil and water on-site, CobBauge avoids wasting or exporting precious resources.

4 Flooding and sea level rises

CobBauge requires a water-resistant masonry plinth and should never be built on flood plains. Clay and plant fibres in the mix are vulnerable to prolonged moisture and mould, while floodwater can leave harmful residues in the plinth cavity. Building safely means avoiding sites at risk from heavy rain or rising seas.

5 Climate-driven impacts: heatwaves and urban heat islands

CobBauge is less likely to be used in dense urban areas and more likely to be used in low-density rural areas.
However, in the Himalayas there are cities with multi-storey buildings in earth construction.

ADAPTATION OF TRADITIONAL COB

Rather than focusing only on infrastructure, adapting individual buildings is key. Traditional cob homes could be upgraded by adding an insulation layer, creating a CobBauge-like mix, though care is needed to bond old and new layers effectively. Experimentation has shown it to be very practical.

Historic examples show earth can build tall, but today’s fire rules add challenges. Wider use of CobBauge in new developments offers a practical path forward.

INTERREG PROJECT COBBAUGE

CobBauge was a six-year Franco-British research and construction programme, running from 2017 to 2023, co-funded by the European Union’s Interreg Channel scheme.

Around €4 million supported the work, with 60% provided by the European Regional Development Fund. Six partner organisations from both sides of the Channel joined forces with one clear goal: to modernise traditional cob so it could meet today’s building regulations.

The project sits within the EU’s broader ambition to cut energy use and carbon emissions from buildings, which account for roughly 40% of all energy consumption.

Traditional cob houses are still a common sight in Normandy, Devon, Cornwall, and East Anglia, but while they perform well in comfort and heritage value, many cannot pass modern regulations. CobBauge set out to change that by creating new mixes and techniques that keep the low-carbon benefits of earth while improving insulation and strength.

At its heart, cob is simple: earth mixed with fibres such as straw and water. The CobBauge innovation lies in adjusting the recipe, adding agricultural by-products to increase insulation while maintaining durability. This approach not only keeps homes comfortable in all seasons but also lowers heating bills.

The project didn’t stop at research. It also worked to grow a network of skilled designers, builders, and self-builders. Training and demonstrations were a key part of the programme, ensuring the knowledge of building with CobBauge spreads into mainstream practice.

By using local soil and waste fibres, CobBauge addresses both environmental and financial challenges. It produces less waste, cuts transport, and avoids the embodied carbon of high-energy materials.

Compared with conventional Cob methods, a CobBauge house can use less than half the heating energy and reduce embodied carbon significantly. Just as importantly, the material meets planning requirements that call for new buildings to respect historic landscapes, keeping heritage alive while tackling climate change.

Compared with conventional non-cob construction, Cob exploits subsoil from the site to make the building, avoiding many tonnes of waste per house.

Six organisations from France and the UK combined their expertise to make CobBauge possible. Leading the project was the University of Plymouth, working alongside ESITC Caen, the University of Caen Normandy, the Regional Nature Park of Cotentin and Bessin, Earth Building UK and Ireland (EBUKI), and Hudson Architects in Norfolk. Together, they brought research, design, and practical building skills to the table.

The project’s aim was clear: to create an affordable, insulating wall material with a low environmental footprint, while cutting waste by using soil from the building site itself. Another priority was building a market for CobBauge—expanding networks of trained builders and responding to the growing demand for sustainable construction.

To meet these aims, the project ran in two stages. The first stage (CobBauge 1) focused on developing new mixes and methods, mobilising a community of skilled practitioners, and sharing the project’s goals and results widely to raise awareness.

CobBauge 1: First Phase Work Packages

WP M – Management
Leader: University of Plymouth

This covered the project’s day-to-day running: coordinating between partners, organising meetings, tracking progress, supervising technical development, ensuring quality, and managing budgets and legal requirements.

WP C – Communication
Leader: ESITC Caen

A communication strategy promoted CobBauge throughout the project. The aim was to show its efficiency and potential as a modern sustainable material to a wide audience — from builders, self-builders, and SMEs to architects, engineers, academics, sector agencies, and the general public.

WP T1 – Cob Mixes: Formulation and Evaluation
Leader: ESITC Caen

Traditional cob could not meet modern thermal standards. CobBauge aimed to change that by testing soils and fibres, identifying promising mixes, and trialling them at both small and medium scales. These tests measured thermal, moisture, and structural performance, while also looking at cost and material availability. The goal was to create an innovative building method that met regulations and comfort needs.

WP T2 – Demand and Professional Network
Leader: PnrMCB

This work focused on building demand for CobBauge and engaging potential users. A professional network was developed, connecting government, construction, insurance, and the third sector. Through events and outreach, the network helped identify user needs, share knowledge about cob, and demonstrate the improvements CobBauge could deliver. This foundation would support training programmes and lead to the construction of a large-scale CobBauge building in Phase 2.

CobBauge 2: Proving and Expanding

WP M – Management
Leader: University of Plymouth
Oversight of the second phase ensured smooth communication, regular meetings, quality control, and proper handling of technical, financial, and legal matters.

WP C – Communication
Leader: ESITC Caen
A communication strategy promoted CobBauge’s results to a wide audience — from builders and self-builders to SMEs, architects, engineers, students, policymakers, and the general public — highlighting cob as a truly modern and sustainable material.

WP T3 – Design and Build
Leader: University of Plymouth
This stage tested CobBauge in real life. Four full-scale homes — two in the UK and two in France — were designed and built. Each reflected local climate, occupancy, and housing styles, showing that the optimised mixes from CobBauge 1 worked in practice. Finished with lime render outside and clay plaster inside, the homes proved both practical and attractive.

WP T4 – Measure Performance
Leader: University of Plymouth
Monitoring focused on two things: building performance in use and the construction process itself. Data showed energy savings of around 20% compared to conventional homes, while also demonstrating comfort in both summer and winter.

WP T5 – Training, Network and Demand
Leader: PnrMCB
To spread the knowledge, PnrMCB and EBUKI created training tools and ran the first workshops for professionals. This growing network of trained builders is expected to support the construction of up to 1,500 CobBauge homes over the next decade.

Life Cycle Assessment (LCA)
In UK public procurement, all building materials are expected to undergo a Life Cycle Assessment. This means looking at every stage of a product’s life — from ingredients, manufacturing, energy, and water use, to emissions, waste, packaging, transport, and end-of-life. Sensitive data is shared with assessors under non-disclosure agreements to ensure transparency without exposing trade secrets.

Environmental Product Declaration (EPD)
An EPD is the public-facing result of the LCA. It presents the numbers in a standard format (EN 15804) that covers the entire building life cycle, even after demolition. EPDs are published in online databases and made available as PDFs for specifiers, often also used as marketing material by manufacturers. For government-funded projects in the UK, an EPD is effectively a “passport” that makes CobBauge eligible for use.

Product Environmental Footprinting (PEF)
The European Commission has been piloting PEF as an alternative to LCA and EPD. To avoid duplication, the EN 15804 standard has now been updated (version A2) to align with PEF. All new EPDs must now follow A2, while older A1 versions will need updating. During this transition, A1 and A2 data are not compatible, so software platforms can only read one or the other. Manufacturers and researchers must now decide when and how to upgrade, balancing cost with the chance to demonstrate improvements in their products.

Outputs
For CobBauge, the process includes monitoring during construction, measuring performance in use, producing a full Life Cycle Assessment, and publishing Environmental Product Declarations for its materials and methods.

The Solution

Earth Building in Context
Earth construction has been part of life for centuries in both the UK and France. From cob cottages in Devon and Cornwall to traditional homes in Normandy, these buildings are part of cultural heritage. Yet today they are rarely built, as they do not pass modern regulations. CobBauge reimagines this tradition for the 21st century — keeping its charm while meeting the performance standards required today.

Earth Building Around the World
Earth remains the world’s most widely used building method, housing around a third of the global population. Vernacular forms vary — adobe in hot climates, rammed earth in deserts, and bauge in northern Europe — but they share low carbon footprints and remarkable comfort. What remains less understood is the science behind their natural ability to stay cool in summer and warm in winter. CobBauge brings research to fill this gap.

Earth Construction
CobBauge builds on many earth-based methods. Traditional cob mixes earth and fibres like straw, while rammed earth uses compacted soil, and wattle and daub adds earth to timber frames. CobBauge combines these traditions with innovation: a twin-layer wall system, with one dense structural mix inside and one lighter insulating mix outside. The leaves are in constant contact and profiled to achieve a mechanical key. Natural fibres such as straw, hemp, and flax reinforce the material, improving insulation and comfort.

Cob
Cob is one of the oldest and most sustainable ways of building. It uses local soil and straw, requires little energy other than manpower and produces almost no pollution. In the UK and France, cob houses have stood for more than 500 years, often outlasting modern brick or concrete. With thick walls and natural finishes, and cob regulates moisture and temperature, keeping homes cosy in winter and cool in summer.

Embodied Energy and Carbon
In the UK, there are growing calls to measure embodied carbon through a proposed “Part Z” of the Building Regulations. Although not yet law, industry bodies are already setting carbon targets. This will push materials like CobBauge, with very low embodied energy and carbon, to the forefront. Data for these assessments increasingly comes from Life Cycle Assessment (LCA), which show the impact of materials over their whole life cycle.

Low Carbon Footprint
CobBauge relies on clay subsoil, potentially avoiding the emissions from transporting heavy materials. Minimal processing is required, and when renewable energy is used, the carbon footprint is extremely low.

Sequestered and Biogenic Carbon
By using agricultural by-products such as straw and hemp shiv, CobBauge also locks up carbon absorbed during plant growth. This biogenic carbon makes it a carbon-negative material, helping to reduce emissions.

Traditional Cob and Thermal Comfort
Traditional cob naturally keeps buildings warm in winter and cool in summer through “thermal mass”—the ability of thick earthen walls to absorb heat and release it slowly. Families once even relied on animal body heat in shared homes for extra warmth. CobBauge retains this natural comfort while adding insulation to meet today’s energy standards.

Thermal Mass and Comfort
Earth walls absorb heat from fires, people, or sunlight, then release it gradually, evening out temperature swings. This helps avoid overheating in summer and keeps homes warmer in winter. CobBauge’s layered system is designed to preserve this advantage while adding further insulation, so far on the inside of the structural layer.

Overheating in Modern Homes
Thin, lightweight construction used in many modern homes lacks thermal mass, leading to overheating. UK regulations have failed to address this adequately with “Part O” on summer overheating, but “Part L” focuses only on winter heat loss. As a result, up to 20% of homes are already reported to suffer overheating. CobBauge’s mass walls and breathable finishes make it far more human-friendly.

Ventilation and Comfort
Passive and mechanical ventilation can help but do not fully solve overheating. CobBauge, by contrast, uses its thermal mass to buffer indoor temperatures. Paired with good solar shading and window design, it provides natural comfort with minimal need for energy-intensive air conditioning.

Indoor Air Quality
CobBauge uses clean, inert subsoil and natural finishes like lime plaster or clay wash, avoiding paint off-gassing. Care must be taken to ensure they are mould-free when selected. With careful design, it can also address risks like radon gas in certain soils. This results in healthy indoor air, free from harmful emissions often linked to modern synthetic materials.

CobBauge Innovation
At its core, CobBauge is a modern cob: a 600mm wall made of two layers. The outer structural mix provides strength and thermal mass; the inner insulating mix, rich in plant fibres, delivers modern levels of insulation. Together, they create a breathable, low-carbon, bio-based wall that outperforms many standard construction methods — while keeping the ecological and cultural value of cob alive.

Building Regulations Part O – Overheating

The UK has introduced new rules under Part O to tackle overheating in summer. They cover high-risk urban locations, solar gain through glazing, shading above windows, solar-resistant glass, cross-ventilation, and the use of shutters. With 20% of homes already reported to overheat—particularly upper floors, flats with poor ventilation, and lightweight MMC housing—overheating is becoming a serious issue. However, Part O does not yet address heat entering through opaque walls and roofs. Without better use of thermal mass and radiant protection, the problem will only grow.

Building Regulations Part R – Network Connections

Part R ensures new homes are future-proofed with broadband connections. For Cob and CobBauge, there are special considerations. Dense clay walls can block mobile signals, sometimes requiring cabled routers. While this shielding can help reduce exposure to electromagnetic radiation—which is a real factor for a vulnerable portion of the population—it also means careful planning for connectivity. In other contexts, shielding is created with meshes or fabrics, but in CobBauge it comes naturally.

Building Regulations Part Z – Embodied Carbon

The UK is reluctantly moving toward a new regulation, Part Z, that would require embodied carbon to be measured in all building materials. Although not yet law, targets such as the RIBA 2030 Carbon Challenge are already guiding practice. This shift plays directly to the strengths of CobBauge, with its very low embodied carbon. Calculations use datasets like the Inventory of Carbon & Energy and Environmental Product Declarations (EPDs), but experts stress the need to measure the whole building—not just structure, but also services, finishes, and infrastructure.

CobBauge represents a bridge between past and future. It draws on centuries of cob tradition in the UK and France, proven to provide comfort and durability, while addressing today’s environmental challenges. By combining a structural cob layer with a new insulating mix, CobBauge meets modern standards for energy efficiency, carbon reduction, and resilience against overheating.

As building regulations evolve — including addressing summer overheating and measuring embodied carbon — CobBauge stands out as a material ready for the future. It uses local soils and agricultural fibres, locks up carbon, and creates homes that are healthier, more environmental, and deeply connected to heritage. In short, it offers a natural solution to some of the biggest challenges facing construction in the 21st century.

Creating an Innovative New Earth Walling Material

How do we know CobBauge works?

To prove that an earth-based material like CobBauge could meet today’s strict building regulations and campaign targets; researchers combined laboratory science with real-world construction. The aim was to show that walls made of subsoil and plant fibres can be strong, durable, insulating and healthy to match modern standards and aspirations.

Lab Measurements

Twelve soils—six from the UK and six from France—were tested alongside six natural fibres, including straw, hemp, flax, and reed. Small- and medium-scale samples were analysed for strength, insulation, moisture control, and acoustic properties. The results showed that the right balance of clay and silt in the soil provided the structural cohesion needed, while fibres improved thermal and mechanical performance. These tests laid the groundwork for a material that was both regulatory-compliant and environmentally low-impact.

Prototype Buildings

Lab-work alone wasn’t enough; the team needed to see how CobBauge performed at full scale. To do this, prototype buildings were designed and constructed — one in the UK and one in France. These buildings allowed researchers and architects to monitor how the material behaved in real conditions, from weather exposure to occupant input through to occupant comfort. The prototypes proved that CobBauge walls not only meet the insulation and strength requirements of UK and French building codes but also retain the health and indoor air quality advantages of traditional cob.

Optimised Mixes

From all the experiments, four “winning” recipes were chosen for real-world use. These combined specific soils with hemp shiv fibres. Each mix offered a balance of strength and insulation, showing how natural, locally available resources can be fine-tuned to meet modern construction needs.

Training and Knowledge Sharing

Training was at the heart of the CobBauge project. Led by Earth Building UK and Ireland (EBUKI) together with the Regional Nature Park of Cotentin and Bessin (PnrMCB) in France, the programme developed resources to connect builders, designers, and professionals across both countries. A shared directory was created, listing stakeholders interested in using CobBauge and highlighting exemplar buildings that showcase sustainable methods, site organisation, and environmental impact. This living database helped the network grow and gave members a reference point for future projects. A whole YouTube channel has been established with many bilingual videos.

To strengthen this network, workshops, site visits, and exchange meetings were organised, allowing participants to share experiences and build demand for CobBauge. These discussions shaped the CobBauge Development Plan, a roadmap that set out future actions and summarised what the community had learnt. Training was tailored for two key audiences: practitioners working on site and professionals such as architects and engineers. Content was adapted to their needs, from practical building skills to structural and environmental considerations. At the end of the programme, graduates were added to the directory and network, ensuring they remain visible and connected as CobBauge moves from research into wider practice.

International Influence
CobBauge has not only shaped building practices in the UK and France but has also influenced discussions far beyond. The project connected with practitioners and artisans at international earth building conventions; and researchers working on earth construction, including those exploring robotic additive building methods. These collaborations addressed shared challenges — from proving performance to gaining building regulation approval — ensuring that earth-based methods gain credibility on a global stage.

Research Impact
Through partnerships with Terran Robotics in the US, the Australian Earth Building Association, and the Cob Research Institute in Berkeley, CobBauge research has informed international standards. Its studies on thermal performance, density, and material properties are providing data that will help shape building codes in both Australia and the USA. The project is also gathering evidence on how natural insulation layers can be added to existing earth walls, offering pathways for upgrading heritage buildings with minimal impact.

Regulations and Guides
CobBauge has contributed to practical resources that make earth construction more accessible to professionals and regulators. Illustrated guides produced by French organisations such as Agence Qualité Construction and CTMNC set out good practices and methods for cob. Presentations and bilingual resources available on the CobBauge and YouTube websites continue to share knowledge widely, helping builders, designers, and policymakers understand how cob can be a part of modern construction.

Future Impact

The first domestic CobBauge home is completed in Norfolk. It marks an important milestone, offering a springboard for architects and builders to take this innovative twist on a traditional method into mainstream practice. By comparing the Portsmouth, Norfolk, projects with the French prototypes, researchers will gain valuable insights into performance across different climates and building traditions.

Looking ahead, one of the main challenges is the cost of labour. Here, CobBauge’s link with Terran Robotics offers promise: robotic construction could cut time and expense dramatically. Prefabricated panels, already tested at the University of Plymouth and ESITC Caen, also point to faster, more efficient ways of building with CobBauge.

Future research will continue to refine and adapt the material. There may be opportunities to explore additives inspired by hemp-lime, though care must be taken to maintain moisture-breathable properties. CobBauge also has potential for digital fabrication: unlike concrete or plastics, its natural fibre-based insulation mixes could be sprayed or pumped for 3D printing of building elements, opening doors to innovative methods of construction.

Another opportunity lies in retrofitting. Traditional cob houses could be upgraded with CobBauge’s insulating mix and protective lime render or plaster, improving comfort while respecting heritage. Challenges remain — from bonding new and old layers to detailing around eaves, plinths, and services — but many of these can be solved with existing components.

The wider construction sector is also looking to prefabrication under the “build back business as usual” agenda. Factory-made panels and modules promise better working conditions, reduced waste, and higher quality. While CobBauge presents challenges — its weight, drying times, and handling — solutions such as forced air drying or careful framing may help bring it into this space.

Practical considerations are also shaping CobBauge’s future. On exposed sites, long drying times mean that temporary weatherproof enclosures ideally should be provided during construction. While these add cost, they also prevent delays and material damage, and a proper cost-benefit analysis could show them to be worthwhile.

Finally, ongoing monitoring will be essential. Measuring how heat flows through CobBauge walls in both summer and winter will give deeper insight into its natural ability to balance indoor comfort and humidity. These studies will ensure that CobBauge not only meets today’s performance standards but also proves itself as a healthy material for the decades ahead.

Conclusion

CobBauge represents more than a building material — it’s a vision for how the construction industry can reconnect with the earth while meeting the demands of modern life. What began as a cross-channel collaboration between France and the UK has grown into a model for sustainable innovation rooted in heritage. By refining the simple mixture of soil, fibre, and water, the project has shown that centuries-old techniques can deliver the comfort, performance, and durability expected of 21st-century homes.

Its research will inevitably influence international standards, inform modern building codes, and inspire professionals to think differently about how we build. The first CobBauge homes now rising in Norfolk and Normandy are more than prototypes—they’re symbols of a shift toward low-carbon, climate-resilient construction.

As the world faces rising temperatures, material shortages, and growing energy demands, CobBauge offers a grounded solution: local, renewable, recyclable, and beautifully human. It stands as proof that progress doesn’t always mean inventing something new — sometimes, it means rediscovering the wisdom of the earth and shaping it for the future.

GBE Team Guest Author

Name: Aarushi Bajpai

Images:

GBE Team Guest Author

Name: Aarushi Bajpai

CabBauge cut away wall section showing structural mix and insulating mix, sloping mechanical key between layers and hemp fibres used in reinforcing layers

CobBauge wall under test, Plymouth Univeristy Laboratories CobBauge 2 Mixes Structural and Insulating