This free standing tree house in Ljubljana, Slovenia by Ravnikar Potokar Arhitekturni is made of spruce plywood protected by a colorless, natural-finish nano-varnish, and topped with a weatherproof cardboard roof. There are no explicit DIY instructions, but you may be able to replicate it yourself just by looking at the pictures. [Via Architizer]
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Funny--my husband and I just built a backyard chicken coop that looks strikingly similar to this. It's raised on stilts, has a slanted roof and wooden slab siding, and a ladder in front for the chickens to climb up. Maybe we will have to build a matching treehouse next!
"Colorless, natural-finish nano varnish." Nano varnish! What is that? "Weatherproof" cardboard? I am guessing that Kristina L's chicken coop probably has a better roof on it than cardboard. This is ridiculous.
What a brilliant design - slanting the posts (4x6's?) seems like it would add significant sturdiness! And the x-bracing rather than typical parallel joists is another great idea.
If there's such a thing as weatherproof cardboard, I wanna know where to buy it, LOL!
I'm pretty sure that if it's free-standing, it isn't a treehouse - which, as the name implies, traditionally involves a tree.
Right, so I'm from Slovenia and I'm familiar with this project and I've just read the description of it on their website.
The house in Slovenian language is called 'House BY a tree' so something got lost in translation here. The house is meant for kids and also to hold a tree that can't support itself any more. Waterproof cardboard is also just a bad translation, I think. The roof is made out of this:
http://picbase.turbosist.si/slonep_galerija2/gradnja/streha/11.jpg
Not sure what that's called in English but a direct translation would be 'bitumen cardboard'. It's light and it lasts forever. If you don't know what nano varnish is you should google it, it's been around for years now. It's a varnish that doesn't contain silicon, oils or waxes and it's for protecting porous materials against dirt an mould. It's basically the sh*t, only you've ever heard of it and made an unnecessary snarky comment.
In my opinion it's very cool. And it fits into the cultural landscape really well too. Here we have a lot of these little houses on tall stilts called 'preža'. They're for hunters and they look like this:
http://www.pictureslovenia.com/media/img/pic/500/866/1761401578450942.jpg
And the link to the house's description on their website with more photos:
http://www.ravnikar-potokar.si/robert_potokar/realizacije/hisica_ob_drevesu.aspx
There :)
Wai is right, I am being snarky about it. Sometimes these posts have so short a blurb about a project that it's unclear what is "green" about the materials specifically mentioned. It's only made more confusing by a poor translation to English.