Super durable natural material, if spread on the roof, it won't rot for 300 years

In 2012, European scientists discovered a carnivorous microalgae in Danish waters that can paralyze other organisms by releasing large amounts of toxins in the water. At the same time, they can also eat large fish. At one time, the inhabitants of the Nordic coast were afraid to go to sea, even fishermen had to wear special waterproof clothes to dare to go out to sea just because of this microalgae.

But for the inhabitants of the island of Læsø, Denmark, they have been eating algae since childhood and so far, they have not found any algae that can make them feel afraid. When people do not dare to go out to sea, they are the only ones who return to the shore to collect seaweed and seaweed.

People harvest seaweed.

"This is the most delicious food in the world, rich in alginic acid, vitamins and protein," said Vallin, a native of Denmark. "Most Norse people in the past didn't eat seaweed because it was bitter and strong, but during the Black Death and the Thirty Years' War, fishermen who lived along the Danish coast survived. thanks to all these seaweeds, seaweeds".

Vallin's mother, a native Danish fisherman in the North Sea, said that she went fishing with her father when she was 7. Her father later died during World War II, and the family moved to the island of Læsø. live and never leave.

Seaweed has significant effects on leukemia and various ulcer symptoms.

The island of Læsø is about 15 km from the mainland of Denmark, with an area of ​​101 square kilometers and less than 1,800 permanent residents, it is the most densely populated municipality in Northern Europe.

The island of Læsø is one of the famous places in Europe, as currently the island is one of the major exporters of seaweed, besides fishing, the locals spend the rest of the time collecting all kinds of seaweed. natural after drying. It is said that in addition to its antioxidant properties, seaweed has significant effects on leukemia and various ulcer symptoms.

Location of the island of Læsø.

But what really attracts people in this island is dozens of seaweed houses with a history of more than 300 years, in 2012, UNESCO sent experts to survey and come to the conclusion: "The seaweed houses This place has a long history, dating back about 300-350 years, with a layer of seaweed on the roof more than a meter thick, with a total weight of 35-40 tons.

Although the seaweed house is not listed as a World Heritage Site, experts still appreciate its "unique", because the life span of a conventional reinforced concrete roof is only 50- 80 years, while seaweed has a much longer life span.

Roof covering material made from seaweed.

The first person to try to build a roof out of seaweed was a fisherman in the 17th century. On his way back, he saw the wooden plank of a shipwreck floating up. Then he picked it up and threw it ashore. A year later, the fisherman discovered clumps of eel algae growing on a wooden plank that had previously been dried, and no matter how heavy the rain, the raindrops would not be able to penetrate the dried seaweed. Accordingly, when his roof was punctured after the storm, he picked up that board to repair his roof.

In the years that followed, the people of the island learned from each other and improved the process of drying, tying eel algae, and gradually forming a unique craft of the island. In the past, there were more than 400 seaweed houses on the island, and some roofs were as thick as 1.5 meters, which greatly improved the island's ability to cope with storms and cold winters. .

However, in 1910, a wave of fungi broke out in the seawater caused by rampant industrial effluents in Denmark, and the eel algae, which had extremely high water quality requirements, died out en masse. Therefore, people had to replace eel algae with other materials to make roofs.

The seaweed roof significantly improves the ability of the people on the island to cope with storms and cold winters.

In 2012, the UNESCO report on the seaweed house made people pay attention to this age-old skill, and accordingly, many people chose to reuse eel algae to make their home, but how and Their technique is completely different from before.

The advantage of this job is low cost, not only sun protection, waterproof.

Take for example the modern version of the house made of seaweed. Once the structure of the wooden house is completed, a waterproof membrane will be placed on the sloped roof, then the previously collected and dried seaweed is bundled into circular strips which will be fixed to the roof. by rope. This work can be done by an adult man and takes about 3 days (excluding harvesting and drying).

The advantage of this is low cost, not only sunscreen, waterproof, insect-proof, but wooden roof structure will also become more durable.

However, for traditional seaweed houses, people have to make 4 to 5 linings to reach a thickness of one meter. Then the roof will never need maintenance. Even if the waterproofing membrane is punctured, the house will not leak. And people who live in it for 300 years won't have to worry about bugs, as the smell of seaweed will repel most bugs.