Turf houses, a construction directly out of the Icelandic sagas

turf houses grass roof

Iceland can be a wild place for architecture, especially because of the lack of materials. But for centuries turf has been an alternative.

Iceland is an extreme country with harsh conditions and a unique climate, because being a practically polar climate throughout the island, it is not particularly cold. Summers are colder than usual in Europe, but winters are not.

The image of its landscape is that of the tundra, which is a bioclimatic landscape (biome) characterized by its frozen subsoil (permafrost), lack of arboreal vegetation, soils covered with mosses and lichens, and humid areas with turf bogs.

Its volcanic character limits the material resources for construction in an undoubted way since, unlike Scandinavia, it lacks wood. 

To obtain the comfort, the thermal isolation in the constructions is a fundamental necessity and, in particular in the cold countries, an essential objective; but in Iceland they cannot be used thick walls of wood to protect themselves, since they do not have it. 

Building with turf

turf houses iceland

In Iceland the soil is rich in turf, the early phase of coal, in which the product is light, manageable and insulating. 

Dry turf can have a thermal conductivity similar to that of a not very good conventional thermal insulator, as well as an acceptable mechanical resistance; for this reason, it is used to build directly the walls of the houses, ensuring insulation and stability. 

The construction process begins with the cutting of the turf blocks, as if they were very long and wide bricks, with a 10 to 20 cm edge, and 40 to 50 by 20 to 30 cm, of rope and blackening respectively. With them, the walls are built, which, according to the existing documentation, could be several meters thick. 

Wet turf loses its insulating character, but it must also be remembered that it is almost impermeable when dry, so even if the outermost layers get wet as a result of persistent snow, the thickness of the walls could ensure the dryness and insulating capacity of the inner layers. 

The completely dry wall can be equivalent to 80% of the thermal resistance of a commercial insulator of the same thickness, i.e. a lot, and partially wet perhaps 20 or 30%, even a very significant resistance due to its great thickness.

The main disadvantage is that these turf walls are fragile and must be regularly rebuilt after a few years, as the rotting process continues to develop, especially in the outermost layers and those exposed to humidity, but overall, given the extreme conditions of the Icelandic climate, the result in terms of thermal insulation is good.

The vegetation, which always covers the roof and stabilizes the whole when the turf layers are crossed and sewn with the roots, can also cover the walls, especially in spring and summer. The vegetation on the roofs must even be mowed occasionally to prevent animals from climbing up to graze.

As a whole, these houses integrate visually, materially and conceptually with the landscape, forming part of it as yet another natural element. In the book Gente independiente (Independent People) by Icelandic Nobel Prize winner Halldór Laxness, a character talks about the house he has just built saying “and there is the house, as if it were part of nature itself”, pointing out how vernacular architecture can be part of the landscape. In the same book, when he shows the house to his wife, as a great merit, he comments: “Wait until next summer and there will be no difference between the roof and the field”.

 

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