A dissertation project building on traditional Viking methods of thatching eelgrass is helping make this seaweed a popular choice of modern building material. An old method of thatching seaweed, used by Vikings on the Danish island of Læsø, has been updated. The technique could be adopted more widely as a modern and environmentally friendly option in construction projects. The project, Seaweed Thatch Reimagined, looks at using eelgrass to make prefabricated panels for either roofs or façades. Eelgrass is not immediately waterproof but becomes so after approximately one year outdoors. Therefore, it is not suitable for all climates, however, it has proven successful on the island of Læsø and would have similar potential in other regions with a dry climate. Colloquially known as a seaweed but actually a type of seagrass, eelgrass is common across the UK and Scandinavia.