A curious building with white curving walls features in many tourist photographs of Berca village in Buzău county, Romania. The hand-hewn texture of the walls, the strange angles—reminiscent of a children’s book—it’s as if a gingerbread house has leapt off the pages and into real life. 

Despite its fairytale appearance, it has a fairly prosaic function—it’s a small restaurant that serves Romanian food to visitors. As you walk through the doors, you’ll see a traditional stove. And on the other side of the structure, placed in a four-leaf clover pattern, are four tiny houses. They have similar walls too: rustic, rough, and curved. Look closely, and you will see marks left by industrious fingers. 

These unusual cob buildings belong to 44-year-old Nicoleta Marin, an elementary school teacher passionate about eco-friendly lifestyles and who has brought back a taste of traditional architecture to the Sub-carpathians. Set against rolling green hills in an area otherwise filled with concrete single floor homes, they paint a pretty and otherworldly picture.

In 2014, Nicoleta participated in a workshop hosted by Ileana Mavrodin, the architect who is credited with introducing cob constructions to Romania, where historically people had only used clay. Afterwards, Nicoleta began to dream of building a cob village in Berca, Buzău county. It’s an UNESCO-protected area, so it seemed like a good spot to incorporate green design. 

Ileana designed the cob village project, the local labourers did the heavy lifting, but it was Nicoleta who spent every day onsite for three years until 2015 when the project was completed. 

A local deeply invested in the process, Nicoleta was involved with every step of the construction. She created the cob mix, built and painted walls, and sanded wood. She chose materials that could be found locally, and mixed them herself with a backhoe. She also repurposed used windows of abandoned cars, and collected shards from the local glass factory.

There’s no perfect recipe for cob building materials. Everything depends on the composition of the soil, and the quality of ingredients. Cob is a mix of clay, sand, straw, and water. Romanians have used a similar blend for centuries to create clay bricks and fill wooden structures. Except back in the day, they used horse dung instead of sand. The process comes together with a lot of trial and error. Nicoleta’s challenges were apparent right from the beginning. 

“No one believed that anything would come out of this soil. For the villagers, it was a joke that I wanted to build a clay house. With houses like that, they had struggled to seal them with plasterboard, and now I wanted to do it too, like in the old times.” Reflecting their confusion, she mused, “Why would you do something like that?” 

Some of the cob mixes weren’t usable, and had to be thrown away. Once, when the mixture was badly crafted, part of a wall fell. Another wall had to be rebuilt because the region suffered from heavy rainfall. But each time she faced a setback, Nicoleta powered through and found solutions. 

Nicoleta was determined. “I wanted to prove that you can live in a cob house, and even have a bit of comfort. The interior design is minimalist to highlight the beauty of the handmade walls, uneven as they are,” she said.

Today, the cob village is open to tourists and architectural enthusiasts. School children, accompanied by their teachers, visit the village to learn about cob. They cook together using locally grown produce, and even create small clay houses of their own.

Ileana Mavrodin, 67, was born in Timișoara, west Romania. After living in Canada for 12 years, she took a trip to her country of birth. The journey changed her life. During her travels, she had been reading a book called The Hand-Sculpted House: A Practical and Philosophical Guide to Building a Cob Cottage by Linda Smiley, Ianto Evans, and Michael A. Smith. When she discovered a plot of land for sale in Sasca Romană, Caraș-Severin county, near the Nera river, she decided to follow the path laid out in the book. Giving up her life in Canada, she used the money she’d saved for a course about cob in the US. She wanted to build a very different kind of home. 

When she first began the project in 2004, her friends and family were confused. Why leave a comfortable expat lifestyle to return to your homeland and build a glorified hut? But Ileana was tired of working in an office, and wanted to spend more time out in nature. Building a cob house seemed like the perfect solution to her. 

When the villagers heard that a lady from Canada wanted to build a house in their community, they expected a fancy, modern building. When the workers she hired realised that she wanted a cob structure, they abandoned the project. 

“They have worked with plasterboard and concrete, and I asked them to work with clay again,” Ileana said. “For them, it was like going back in time.”

World over, building with cob was a common construction technique in the 13th century. The oldest cob structures still standing are in the UK, New Zealand, the Arabian peninsula, and Burkina. Like many traditional practices, it lost steam during the industrial revolution. Slowly, people began to replace natural materials with modern and easily manufactured ones. 

Modern doesn’t always mean better in the long run. The chemicals in the walls caused allergies and other health problems for residents. Tired of this phenomenon, many people decided to turn to natural building materials and revive ancient building practices. 

In 2004, when she began building  Casa Verde cottage, Ileana wanted to change the way Romanian people saw clay and cob houses. Instead of dusty, shabby structures, she wanted to show them that these buildings could be safe, durable, sustainable and aesthetically pleasing. 

As the trend of natural and sustainable buildings began to gain traction in countries like the U.S, the east also experienced a resurgence. Casa Verde cottage was featured on a website that celebrated natural buildings. Almost overnight, the number of people interested in Ileana’s work shot up. English volunteers showed up to learn how to work with cob. More people became interested in her project. To introduce more people to the concepts she was so passionate about, Ileana began to organise summer camps onsite. The first participants were IT employees, tired of computers, and wanting to spend some time in nature. 

These days, she guides attendees on a variety of topics including soil, design, building materials, natural paints, and more. They work together to craft cob walls, and create different plasters (clay-sand, clay-sand-lime, or sand-lime). They’re eager to learn from the mistakes she’s made along the way, and understand how she’s gone about fixing them.

Building a house used to be a community effort in Romania. One of the traditional ways to work with natural materials were bricks made of clay, straw, water, and horse or cow dung. Historically, horses or oxen mixed the materials, trampling the ingredients. Later, human feet replaced livestock. 

The mix was then shaped into bricks by hand or with the help of a wooden frame. Once shaped, they were left out in the sun to dry. Afterwards, they were assembled with a binding agent made of clay and water. A house built in this way would last for decades, but every year, the owners would have to repair cracks that would appear when the materials became too dry, and spaces grew between the bricks. Trying to solve this problem, some people tried to seal these houses with modern materials. Unfortunately, this made the houses too airtight and ran the risk of growing mould. 

An advantage of using cob is that it doesn’t require a wooden frame or fixed structure. The wet mixture is piled in layers to create a monolith. It’s quicker and easier to build with, cheaper, more durable, and offers better temperature regulation. It’s cool during summer and warm during winters. Some parts of the house, like the floor or the windows and doors, can utilise different natural materials such as burned or crushed clay bricks, lime, and ash. This will ensure that the mixture solidifies further.  

Additionally, the cottages are weatherproof, termite-proof, fire retardant, and earthquake-resistant. Overall, a healthier and safer choice. The natural materials have been a godsend to people who suffer from a myriad of health issues. 

“There are people who can’t live in a conventional house anymore because of the allergies triggered by the chemical compounds,” Ileana said. “They wanted natural houses and started to look for alternatives.”

Truly sustainable cob houses can be returned to the ground from which they are created. They leave nothing behind, and the land remains unscarred and can be used for other purposes.

Apart from the Cob Village, Ileana also designed a cob house, in Sângeorz – Băi, which uses bales of straw as part of its structure. One of her best-known designs is for a cob castle, in Porumbacu de Sus, which has been recognised internationally. Both buildings are situated in Transylvania, Romania.

The castle has only furthered the trend of natural materials, shifting mentalities about cob and clay houses. There has been a renewed interest in natural constructions. A Romanian Facebook group on the subject has more than 30,000 members. People have begun posting photos of their cob houses in various states of construction, asking for advice or just sharing their experiences. This is a huge change from 2004, when Ileana’s home was probably the only cob house in Romania. 

In addition to the finished house she built, and another that is an ongoing project, Mavrodin’s courtyard features an open kitchen for warm summer days, a shower cabin, a storehouse, and a small house for children. The participants of her summer camp created these structures as practice, and while she may not keep them all, for now they continue to delight visitors. 

Casa Verde, Ileana’s passion project, is now a local landmark. As for the locals who once regarded the Canadian lady’s cob house with confusion and annoyance? They’re quite proud to know her — after seeing her on TV, of course.