Tuesday, 18 November 2014

ABC Wednesday, S, Scandinavia,Sod roof .

The first time I visited Norway I saw these remarkable houses covered by grass roofs. I was fascinated by the look of them. A long time before, I had met a Norwegian young man in one of the workcamps, where we worked during the holidays as volunteers. He told me a lot about Norway and also about the grass roofs. He said that some farmers put their goats on top of the roofs to keep the grass short and to prevent trees from growing on the houses.



Maihaugen in Lillehammer


Valdres Folkemuseum


Valdres Folkemuseum

"A sod roof or turf roof is a traditional Scandinavian type of green roof covered with sod on top of several layers of birch bark on gently sloping wooden roof boards. Until the late 19th century, it was the most common roof on rural log houses in large parts of Scandinavia.


 The load of approximately 250 kg per m² of a sod roof is an advantage because it helps to compress the logs and makes the walls more draught-proof. In winter the total load may well increase to 400 or 500 kg per m² because of snow.


 The birch bark underneath ensures that the roof will be waterproof.

The term ‘sod roof’ is somewhat misleading, as the active, water-tight element of the roof is birch bark. The main purpose of the sod is to hold the birch bark in place. "( Wikipedia)


.A sod roof has a lot of advantages: Firstly it is cheap, for the materials used for it, like birch bark and grass turf, are available in abundance.
Secondly: It's an ideal way of insulation in the cold and long Scandinavian winters.

But it requires a lot of time! No problem, for neighbours and friends are invited to join in a roofing party

    History


    Sod roofs on farmhouses in Gudbrandsdal, Norway. Photo: Roede.


    This practice of covering roofs with birch bark and grass sods in Scandinavia, dates back to prehistory. The Vikings and People from the Middle Ages built their houses this way.This lasted until the beginning of the 18th century. Gradually houses in towns were built with tiled roofs and sod roofs almost disappeared, This was considered to be a threat  to ancient traditions. This caused a general revival of vernacular traditions, including these sod roofs.


    Maihaugen



    Mountain lodges and holiday homes with sod roofs became very popular. Open air museums like Maihaugen in Lillehammer, and reservations all over Norway, contributed to a better knowledge of the ancient culture of Norway and the rest of Scandinavia.



    Røros, old mining town


    Røros, old mining town.

     Isn't it wonderful to have flowers on your house?

    From these reservations, sod roofs have begun to reappear as an alternative to modern materials. The more recent idea of the green roof is developed independently from the traditional sod roof, but could benefit from the experience gathered during hundreds of years in Scandinavia.

    Birch bark


    Doukhobor house in Yefremovka, Georgia, with a sod roof.

    Birch bark is important for a sod roof, for it is strong, water-resistant and soil-resistant enough to last for generations, although 30 years was considered the normal lifespan of a sod roof in most places. Birch is common everywhere in Northern Europe, and its bark is easily stripped from the trunk in spring or early summer, while the sap is running.


    "Bark has to be weighted down with a heavier material to prevent it  from curling or blowing away. Therefore sod is used and this  has an additional advantage because it is an insulator.


     The first layer of sod was traditionally placed with the grass down, as the wilted grass would protect the bark from acid humus and act as a drain. The grass of the second layer faced upwards to establish a solid surface. Grass roots would eventually permeate the bottom layer to create one solid structure. The finished roof would in time look just like a flower-studded meadow. "( Wikipedia)




    With thanks to Denise Nesbitt,  who created ABC, and Roger, who took over from her. For more interesting ABC posts click on the logo in the sidebar. This week we are looking for words beginning with  S.



    26 comments:

    Sallie (FullTime-Life) said...

    Those are wonderful Wil! Oddly we saw a few sod roofs (not as pretty as these) in Alaska -- also cold cold cold in winter .

    Sylvia K said...

    Those are wonderful indeed, Wil!! What a great, interesting post for the day -- as always!! Great photos! Thanks for sharing!! Hope you have a great week!!

    Cloudia said...

    Thank you for sharing Wil



    ALOHA from Honolulu
    ComfortSpiral
    =^..^= . <3 . >< } } (°>

    Indrani said...

    I always learn something new through your posts.
    Good one on S. :)
    Happy ABCW!

    Rajesh said...

    Great shots of the unique houses with grass roof top.

    Trubes said...

    A most interesting post Wil.
    Although I wouldn't fancy going up there with a grass cutter if I didn't have a goat!
    Good idea for cheap insulation though !

    Best wishes,
    Di.x

    ABCW team.

    Roger Owen Green said...

    What a livable locale!

    ROG, ABCW

    Susan Moore said...

    I love this idea! It is starting to gain some popularity here in Texas. Some of the high-rise buildings are also creating gardens and even bee hives on their rooftops in Austin.

    jeannettestgermain said...

    As always very interesting, Wil! Thank you for the explanation how it works:) Wouldn't mind to have a sod roof, but I think it might be too dry and hot in the summer here. Hope all things are well with you?

    Jane Hards Photography said...

    Always learn something new here. Never heard of a sod roof before. Blogging is still one of the best ways to learn of each others world.

    ChrisJ said...

    I saw some of these when we were visiting Norway. I think it's a great idea and the goats are an inspiration. I believe there are some of these in parts of Scotland.

    happywonderer said...

    So interesting! What a wonderful collection of photos of the sod roofs you have shared with us!

    Hildred said...

    Great post, Wil, - these are reminiscent of the sod roofs on many early prairie cabins built by pioneers.

    GreensboroDailyPhoto said...

    Such a brilliant thing to have a sod roof. You shared so much good information!

    Mersad said...

    I have never seen such roofs before. I have visited Norway myself and love everything about it.

    Visiting through ABC Wednesday.

    Mersad
    Mersad Donko Photography

    Ni de Aqui, Ni de Alla said...

    Very interesting! I enjoyed reading all about it, great pictures!

    Ann, Chen Jie Xue 陈洁雪 said...

    Coming from Borneo where we have so much rain, I always wonder if water will leak down the roof into the house. As an adult, in Singapore, the university my husband taught and where I lived for 16 yeas, they built a building with turf on the roof and slopping wall. I remember the same question I asked when I was a kid.

    Joy said...

    Fascinating, the thought of goats nibbling on a roof is going to stick in my mind.

    Lmkazmierczak said...

    Fascinating info♪ http://lauriekazmierczak.com/spool-yard/

    Anita said...

    Such pretty pics like picture postcards :)
    Have a great weekend, Wil!

    Melody Steenkamp said...

    Zo anders dan Nederland he..... ik zou daar graag eens ronddolen.... mooie foto's hoor!

    ladyfi said...

    Wonderful shots. Roros is one of my favourite little towns!

    sharplittlepencil.com said...

    Wil, you know the old saying, "Everything old is new again?" Thinking about how hard developers have worked at that green roofing, when they could look to Scandinavia for the entire package... but then, they could not patent it and make money, right?! Yikes.

    Also reminds me of Irish thatched roofs, and the straw insulation of many European houses.

    Wonderfully told history, great images. Thanks for this! Amy

    Black Jack's Carol said...

    Flowers on one's roof are Special indeed. So much to learn from your Study of grass roofs. I wonder how much trial and error it took to figure out the part about placing the first layer of grass down, and the second up. Thanks for this. Something brand new to think about. Very enjoyable.

    Miss_Yves said...

    Très curieux!
    Merci de votre visite sur mon blog

    Powell River Books said...

    The Viking ruins in Newfoundland had sod roofs and walls. They looked well constructed for the cold winters, but they probably learned well at home in Norway. - Margy