The UK’s First cobbauge home

All photographs on this blog are courtesy of Joakim Borén

Where is the first UK CobBauge home and who was behind the innovative build?

Nestled in the town of Fakenham in Norfolk, England, sits a first of its kind here in the UK - our very first CobBauge home. Innovated and curated through a dedicated collaboration between Hudson Architects and Grocott & Murfit, the end result is a mastery of design and build.

I was fortunate to attend an evening in which I learnt first hand insights as well as view the property. In awe, I couldn’t not share this with you! 

So what is a CobBauge home?

Effectively, a CobBauge home is made from the earth and replaces the typical brick construction that we’ve come to adopt as our traditional method of construction here in the UK.

However, across the world, over a third of buildings are made with earth, even being used for multi storey buildings - this surprised me, I knew our earth was strong but I hadn’t comprehended the sheer capability and strength that this material, when harnessed and optimised effectively, could deliver. 

What does CobBauge stand for?

The word is a combination of French and English and is a reflection of the research collaboration between us and France in bringing earth construction to the modern day. Cob is the English for mud and Bauge is the French for mortar of clay and straw.

How is CobBauge different from a clay house?

Clay, on its own, doesn’t meet todays building standards - CobBauge is about changing that as well as creating a material that is suitable for low carbon construction. 

How did they translate our UK earth into a fully fledged building material?

Funded by the European Union, extensive research and development, mixed with tireless dedication from Hudson Architects, Grocott and Murfit, Plymouth University and Parc natural regional des Maria’s du Contentin et du bessin is what drove this projects success. They were able to identify that if they used Cob as the structural layer and combined it with an outer layer of light earth they could create a structurally sound build with excellent thermal performance. Overall, the wall is 600mm thick with an equal ratio of both materials. With a wall thickness that is over double that of a brick construction it’s of no surprise to learn that there are multiple benefits to this new, yet ancient, building method.  

What are the benefits of CobBauge that were highlighted to us by Hudson Architects and Grocott and Murfit?

It is by far the most sustainable construction material, with its carbon emissions sitting outstandingly low in comparison to steel and still much lower than CLT timber, concrete and fired bricks. Think 0.1 kg co2/kg vs 2 kg co2/kg!

Not only this but the indoor environment surpasses what other materials are achieving. The improved air quality, which was immediately noticeable on entering the building, is due to varying factors. The walls are hygroscopic and absorb both VOCs and EMF’s - in other words, it takes the pollutants out of the building as well as reducing electromagnetic field exposure (cue everyone taking their mobiles from their pockets and sure enough, little to no signal) - all conducive to a healthier living environment that naturally enhances your own wellbeing. In conjunction with this, there is a high thermal mass that regulates the indoor temperature and in turn reduces energy use. Furthermore, the acoustic performance was truly remarkable.

In essence, it’s healthier for you, healthier for the planet and healthier to your energy bills.

Where do you source the materials for a CobBauge home? 

For this project, the teams sourced from local quarries - Bilney near Kings Lynn and Setchley near Dereham. The ethos of procuring locally aligns with this CobBauges’ genius loci, to be in harmony with earth and the local environment. The Genius Loci is a spirit of a place. It was fascinating to learn that the structural layer uses earth quarried from the glacial till  - although we were sadly told that no discoveries of woolly mammoths have been reported on this build!

Can you build a CobBauge home at any time?

As with our existing building methods, all builds progress best during the warmer months - the wet weather slows us down and this is no exception for CobBauge, with March to October being the build zone/window for this type of build. It shouldn’t be built outside of this window due to the Cobs natural properties and the process required for it to form and dry into a sturdy structure. On post project review, it was identified that overhead boarding would be hugely beneficial to the construction phase as the material can’t get wet during the build. It’s also important to note that, like other materials, it has a shrinkage rate that needs to be accounted for during the detailing process. The shrinkage is quicker at the start as the material settles into its environment and then levels out over time.

How is a CobBauge home built?

It was stressed that for a CobBauge home to be successful it’s imperative that it ‘has good boots and a good hat’. In essence, it needs to be protected from the elements at the base and the top - this is translated through concrete foundations, a low level brick base structure and a dense roof with a generous overhang with the building breathing through the cob walls.

Once the boots were in place, the team created a shutter system that the cob could be built into - imagine a two sided fence with a gap in the middle standing tall above the ‘boots’. 

With earth, straw, hemp shiv and skips (for mixing and storage) to hand - the build process could begin. Materials are soaked in pre-made pools, blended together and mixed. Once ready, the two layers get put into the shutter system and compressed down where it is then left to cure. From here it’s large timber beams, a roof, internal walls and plastering. 

How can I own a CobBauge home?

That’s an easy one - be the first to own the very first UK CobBauge home, marketed through Sowerbys Fakenham (Keeping it local again!) 

The best parts of this CobBauge Home?

I got wonderfully sidetracked speaking with the team that I forgot to take a photo of my favourite part of this building - aside from all of the above - I loved that one of the internal walls framed a section of unplastered wall, providing a nod and gentle reminder of just how outstanding and forward thinking this build is. I adore the little nod to its history, to 4 years of extensive research and development.

If there’s one thing I can take away from this, it’s that Hudson Architects and Grocott and Murfit should be immensely proud for all they have achieved. When working on projects it can be easy to lose sight of just what was achieved - and this event served as a wonderful reminder for us all to reflect back on the work that we do. We get focused on arriving at a projects destination and forget to look back on the journey and all of the paths and diversions that we took to deliver the end result.

Congratulations to all involved and thank you for the honour of hearing your story and for the privilege of being given a tour.